Run all lua examples in docs as doctests

.cargo/config.toml

@@ -1,3 +1,2 @@
 [build]
 rustflags = ["--cfg", "tokio_unstable"]
-rustdocflags = ["--cfg", "tokio_unstable"]

.luarc.json

@@ -1,5 +1,9 @@
 {
   "$schema": "https://raw.githubusercontent.com/LuaLS/vscode-lua/master/setting/schema.json",
   "runtime.version": "LuaJIT",
-  "diagnostics.disable": ["redefined-local", "lowercase-global"]
+  "diagnostics.disable": [
+    "undefined-global",
+    "redefined-local",
+    "lowercase-global"
+  ]
 }

Cargo.toml

@@ -1,6 +1,8 @@
 [workspace]
+resolver = "3"
 members = [
     "crates/lb",
+    "crates/lb_sqlite",
     "crates/luaffi",
     "crates/luaffi_impl",
     "crates/luaify",
@@ -8,23 +10,52 @@ members = [
     "crates/luajit-sys",
 ]
 
+[workspace.package]
+version = "0.0.1"
+edition = "2024"
+license = "MIT"
+authors = ["luaneko <lumi@lua.re>"]
+homepage = "https://git.lua.re/luaneko/luby/"
+repository = "https://git.lua.re/luaneko/luby/"
+
+[package]
+name = "luby"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
+
 [profile]
 dev.panic = "abort"
 release.panic = "abort"
 
-[package]
-name = "luby"
-version = "0.1.0"
-edition = "2024"
+[[test]]
+name = "main"
+harness = false
+
+[features]
+default = ["task", "time", "fs", "net", "sqlite"]
+task = ["lb/task"]
+time = ["lb/time"]
+fs = ["lb/fs"]
+net = ["lb/net"]
+sqlite = ["dep:lb_sqlite"]
+tokio-console = ["dep:console-subscriber"]
 
 [dependencies]
-clap = { version = "4.5.40", features = ["derive"] }
-console-subscriber = "0.4.1"
-lb = { version = "0.1.0", path = "crates/lb" }
-luajit = { version = "0.1.0", path = "crates/luajit", features = ["runtime"] }
+clap = { version = "4.5.40", features = ["derive", "env"] }
+console-subscriber = { version = "0.4.1", optional = true }
+lb = { path = "crates/lb", features = ["runtime"] }
+lb_sqlite = { path = "crates/lb_sqlite", optional = true }
+luajit = { path = "crates/luajit", features = ["runtime"] }
 mimalloc = "0.1.47"
 owo-colors = "4.2.1"
 sysexits = "0.9.0"
-tokio = { version = "1.45.1", features = ["full", "tracing"] }
+tokio = { version = "1.45.1", features = ["rt", "rt-multi-thread"] }
 tracing = "0.1.41"
-tracing-subscriber = "0.3.19"
+tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
+
+[build-dependencies]
+vergen-git2 = { version = "1.0.7", features = ["cargo", "rustc"] }

bacon.toml

@@ -1,6 +1,10 @@
+default_job = "test"
+
 [jobs.test]
-command = ["cargo", "test", "--workspace"]
+command = ["cargo", "test"]
+watch = ["*.lua"]
 need_stdout = true
+background = false
 
 [jobs.doc]
 command = ["cargo", "doc", "--workspace"]

build.rs

@@ -0,0 +1,13 @@
+use vergen_git2::{CargoBuilder, Emitter, Git2Builder, RustcBuilder};
+
+fn main() {
+    Emitter::default()
+        .add_instructions(&CargoBuilder::all_cargo().unwrap())
+        .unwrap()
+        .add_instructions(&Git2Builder::all_git().unwrap())
+        .unwrap()
+        .add_instructions(&RustcBuilder::all_rustc().unwrap())
+        .unwrap()
+        .emit()
+        .unwrap();
+}

crates/lb/Cargo.toml

@@ -1,16 +1,27 @@
 [package]
 name = "lb"
-version = "0.1.0"
-edition = "2024"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
+
+[features]
+runtime = ["tokio/rt"]
+task = ["tokio/rt", "tokio/time"]
+time = []
+fs = ["tokio/fs", "dep:walkdir", "dep:globset", "dep:tempfile"]
+net = ["tokio/net", "tokio/io-util"]
 
 [dependencies]
-camino = "1.1.10"
 derive_more = { version = "2.0.1", features = ["full"] }
-luaffi = { version = "0.1.0", path = "../luaffi" }
-luajit = { version = "0.1.0", path = "../luajit" }
-sysexits = "0.9.0"
-tokio = { version = "1.45.1", features = ["rt", "time", "fs", "net", "process", "signal"] }
-
-[dev-dependencies]
+globset = { version = "0.4.16", optional = true }
+luaffi = { path = "../luaffi" }
 luaify = { path = "../luaify" }
-tokio = { version = "1.45.1", features = ["full"] }
+luajit = { path = "../luajit" }
+sysexits = "0.9.0"
+tempfile = { version = "3.20.0", optional = true }
+thiserror = "2.0.12"
+tokio = { version = "1.45.1" }
+walkdir = { version = "2.5.0", optional = true }

crates/lb/src/channel.rs

@@ -1,64 +0,0 @@
-// use flume::{Receiver, Sender};
-use luaffi::{cdef, metatype};
-
-#[cdef]
-pub struct lb_libchannel;
-
-#[metatype]
-impl lb_libchannel {
-    #[new]
-    extern "Lua-C" fn new() -> Self {
-        Self
-    }
-
-    extern "Lua" fn unbounded(self) {
-        let (send, recv) = (__new(__ct.lb_sender), __new(__ct.lb_receiver));
-        self.__unbounded(send, recv);
-        (send, recv)
-    }
-
-    extern "Lua" fn bounded(self, cap: number) {
-        assert(cap >= 0, "channel capacity must be nonnegative");
-        let (send, recv) = (__new(__ct.lb_sender), __new(__ct.lb_receiver));
-        self.__bounded(cap, send, recv);
-        (send, recv)
-    }
-
-    // extern "Lua-C" fn __unbounded(&self, s: *mut lb_sender, r: *mut lb_receiver) {
-    //     let (send, recv) = flume::unbounded();
-    //     unsafe {
-    //         ptr::write(s, lb_sender { send });
-    //         ptr::write(r, lb_receiver { recv });
-    //     }
-    // }
-
-    // extern "Lua-C" fn __bounded(&self, cap: usize, s: *mut lb_sender, r: *mut lb_receiver) {
-    //     let (send, recv) = flume::bounded(cap);
-    //     unsafe {
-    //         ptr::write(s, lb_sender { send });
-    //         ptr::write(r, lb_receiver { recv });
-    //     }
-    // }
-}
-
-// #[cdef]
-// pub struct lb_sender {
-//     #[opaque]
-//     send: Sender<c_int>,
-// }
-
-// #[metatype]
-// impl lb_sender {
-//     extern "Lua" fn send(self, value: _) {
-//         let key = __ref(value);
-//     }
-// }
-
-// #[cdef]
-// pub struct lb_receiver {
-//     #[opaque]
-//     recv: Receiver<c_int>,
-// }
-
-// #[metatype]
-// impl lb_receiver {}

crates/lb/src/fs.rs

@@ -1,32 +0,0 @@
-//! The `lb:fs` module provides utilities for interacting with the file system asynchronously.
-//!
-//! See [`lb_libfs`] for items exported by this module.
-use luaffi::{cdef, metatype};
-use std::io;
-use tokio::fs;
-
-/// Items exported by the `lb:fs` module.
-///
-/// This module can be obtained by calling `require` in Lua.
-///
-/// ```lua
-/// local fs = require("lb:fs");
-/// ```
-#[cdef]
-pub struct lb_libfs;
-
-#[metatype]
-impl lb_libfs {
-    #[new]
-    extern "Lua-C" fn new() -> Self {
-        Self
-    }
-
-    pub extern "Lua" fn read(&self, path: string) -> string {
-        self.__read(path)
-    }
-
-    async extern "Lua-C" fn __read(&self, path: &str) -> io::Result<Vec<u8>> {
-        fs::read(path).await
-    }
-}

crates/lb/src/fs/async.rs

@@ -0,0 +1,83 @@
+use super::*;
+use luaffi::{cdef, metatype};
+use std::cell::RefCell;
+use tokio::fs::{DirEntry, ReadDir};
+
+/// Iterator over the entries in a directory.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_read_dir(#[opaque] RefCell<ReadDir>);
+
+#[metatype]
+impl lb_read_dir {
+    pub(super) fn new(iter: ReadDir) -> Self {
+        Self(RefCell::new(iter))
+    }
+
+    /// Returns the next entry in the directory, or `nil` if there are no more entries.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the directory could not be read.
+    #[call]
+    pub async extern "Lua-C" fn next(&self) -> Result<Option<lb_dir_entry>> {
+        Ok(self
+            .0
+            .try_borrow_mut()?
+            .next_entry()
+            .await?
+            .map(lb_dir_entry::new))
+    }
+}
+
+/// Entry inside of a directory on the filesystem.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_dir_entry(#[opaque] DirEntry);
+
+#[metatype]
+impl lb_dir_entry {
+    pub(super) fn new(entry: DirEntry) -> Self {
+        Self(entry)
+    }
+
+    /// Returns the full path of this entry.
+    pub extern "Lua-C" fn path(&self) -> String {
+        self.0.path().to_string_lossy().into()
+    }
+
+    /// Returns the file name of this entry.
+    pub extern "Lua-C" fn name(&self) -> String {
+        self.0.file_name().to_string_lossy().into()
+    }
+
+    /// Returns the type of this entry.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the file type could not be determined.
+    pub async extern "Lua-C" fn r#type(&self) -> Result<lb_file_type> {
+        Ok(lb_file_type::new(self.0.file_type().await?))
+    }
+
+    /// Returns the metadata for this entry.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the metadata could not be retrieved.
+    pub async extern "Lua-C" fn metadata(&self) -> Result<lb_file_meta> {
+        Ok(lb_file_meta::new(self.0.metadata().await?))
+    }
+
+    /// Returns the inode number for this entry.
+    #[cfg(unix)]
+    pub extern "Lua-C" fn ino(&self) -> u64 {
+        self.0.ino()
+    }
+
+    /// Returns the full path of this entry.
+    #[tostring]
+    pub extern "Lua" fn tostring(&self) -> String {
+        self.path()
+    }
+}

crates/lb/src/fs/glob.rs

@@ -0,0 +1,46 @@
+use super::*;
+use globset::GlobSet;
+use luaffi::{cdef, metatype};
+use std::cell::RefCell;
+use walkdir::IntoIter;
+
+/// Iterator that yields paths from the filesystem that match a particular pattern.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_glob_dir {
+    #[opaque]
+    iter: RefCell<IntoIter>,
+    #[opaque]
+    matcher: GlobSet,
+    #[opaque]
+    prefix: PathBuf,
+}
+
+#[metatype]
+impl lb_glob_dir {
+    pub(super) fn new(iter: IntoIter, matcher: GlobSet, prefix: PathBuf) -> Self {
+        Self {
+            iter: RefCell::new(iter),
+            matcher,
+            prefix,
+        }
+    }
+
+    /// Returns the next entry matching the glob pattern, or `nil` if there are no more entries.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the directory could not be read.
+    #[call]
+    pub extern "Lua-C" fn next(&self) -> Result<Option<lb_walk_dir_entry>> {
+        while let Some(res) = self.iter.try_borrow_mut()?.next() {
+            let entry = res?;
+            let path = entry.path().strip_prefix(&self.prefix).unwrap();
+            if self.matcher.is_match(path) {
+                return Ok(Some(lb_walk_dir_entry::new(entry)));
+            }
+        }
+
+        Ok(None)
+    }
+}

crates/lb/src/fs/mod.rs

@@ -0,0 +1,190 @@
+//! Filesystem library.
+//!
+//! The `lb:fs` library provides synchronous and asynchronous utilities for interacting with the
+//! filesystem.
+//!
+//! ## Asynchronous by default
+//!
+//! Filesystem operations are blocking by nature; to provide asynchronicity, luby performs blocking
+//! operations in a background thread pool by default. Synchronous complements to all asynchronous
+//! functions are always provided.
+//!
+//! ## Exports
+//!
+//! See [`lb_fslib`] for items exported by this library.
+use luaffi::{cdef, metatype};
+use std::{
+    cell::{BorrowError, BorrowMutError},
+    path::PathBuf,
+};
+use thiserror::Error;
+
+mod r#async;
+mod glob;
+mod sync;
+mod temp;
+mod walk;
+
+pub use r#async::*;
+pub use glob::*;
+pub use sync::*;
+pub use temp::*;
+pub use walk::*;
+
+/// Errors that can be thrown by this library.
+///
+/// Functions which return this error will **throw**. The error message can be caught by using
+/// [`pcall(f, ...)`](https://www.lua.org/manual/5.1/manual.html#pdf-pcall).
+#[derive(Debug, Error)]
+pub enum Error {
+    /// Attempt to access an object while it is being modified.
+    #[error("cannot access object while it is being modified")]
+    Borrow(#[from] BorrowError),
+    /// Attempt to modify an object while it is in use.
+    #[error("cannot modify object while it is in use")]
+    BorrowMut(#[from] BorrowMutError),
+    /// I/O error.
+    #[error("{0}")]
+    Io(#[from] std::io::Error),
+    /// Walk directory error.
+    #[error("{0}")]
+    Walk(#[from] walkdir::Error),
+    /// Glob pattern error.
+    #[error("{0}")]
+    Glob(#[from] globset::Error),
+}
+
+type Result<T> = std::result::Result<T, Error>;
+
+/// Items exported by the `lb:fs` library.
+///
+/// This library can be acquired by calling
+/// [`require("lb:fs")`](https://www.lua.org/manual/5.1/manual.html#pdf-require).
+///
+/// ```lua
+/// local fs = require("lb:fs")
+/// ```
+#[cdef(module = "lb:fs")]
+pub struct lb_fslib;
+
+#[metatype]
+impl lb_fslib {
+    #[new]
+    extern "Lua-C" fn new() -> Self {
+        Self
+    }
+
+    /// Reads the entire contents of a file.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the file does not exist or could not be read.
+    pub async extern "Lua-C" fn read(path: &str) -> Result<Vec<u8>> {
+        Ok(tokio::fs::read(path).await?)
+    }
+
+    /// Reads the entire contents of a file synchronously.
+    ///
+    /// This is a synchronous complement to [`read`](Self::read).
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the file does not exist or could not be read.
+    pub extern "Lua-C" fn read_sync(path: &str) -> Result<Vec<u8>> {
+        Ok(std::fs::read(path)?)
+    }
+
+    /// Writes the given contents to a file, replacing its contents if it exists.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the file could not be written.
+    pub async extern "Lua-C" fn write(path: &str, contents: &[u8]) -> Result<()> {
+        Ok(tokio::fs::write(path, contents).await?)
+    }
+
+    /// Writes the given contents to a file synchronously, replacing its contents if it exists.
+    ///
+    /// This is a synchronous complement to [`write`](Self::write).
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the file could not be written.
+    pub extern "Lua-C" fn write_sync(path: &str, contents: &[u8]) -> Result<()> {
+        Ok(std::fs::write(path, contents)?)
+    }
+
+    /// Reads the entries in a directory.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the directory could not be read.
+    pub async extern "Lua-C" fn read_dir(path: &str) -> Result<lb_read_dir> {
+        Ok(lb_read_dir::new(tokio::fs::read_dir(path).await?))
+    }
+
+    /// Reads the entries in a directory synchronously.
+    ///
+    /// This is a synchronous complement to [`read_dir`](Self::read_dir).
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the directory could not be read.
+    pub extern "Lua-C" fn read_dir_sync(path: &str) -> Result<lb_read_dir_sync> {
+        Ok(lb_read_dir_sync::new(std::fs::read_dir(path)?))
+    }
+
+    /// Recursively walks the current directory, yielding all entries within it.
+    pub extern "Lua" fn walk(pattern: &str) -> Result<lb_walk_dir> {
+        Self::walk_dir(".")
+    }
+
+    /// Recursively walks a directory, yielding all entries within it.
+    pub extern "Lua-C" fn walk_dir(path: &str) -> lb_walk_dir {
+        lb_walk_dir::new(walkdir::WalkDir::new(path).into_iter())
+    }
+
+    /// Recursively walks the current directory, yielding all entries within it that match the given
+    /// glob pattern.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the pattern is invalid.
+    pub extern "Lua" fn glob(pattern: &str) -> Result<lb_glob_dir> {
+        Self::glob_dir(".", pattern)
+    }
+
+    /// Recursively walks a directory, yielding all entries within it that match the given glob
+    /// pattern.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the pattern is invalid.
+    pub extern "Lua-C" fn glob_dir(path: &str, pattern: &str) -> Result<lb_glob_dir> {
+        let prefix = PathBuf::from(path);
+        let iter = walkdir::WalkDir::new(path).min_depth(1).into_iter();
+        let matcher = globset::GlobSet::builder()
+            .add(globset::Glob::new(pattern)?)
+            .build()?;
+
+        Ok(lb_glob_dir::new(iter, matcher, prefix))
+    }
+
+    /// Creates a new temporary directory.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the temporary directory could not be created.
+    pub extern "Lua-C" fn temp_dir() -> Result<lb_temp_dir> {
+        Ok(lb_temp_dir::new(tempfile::tempdir()?))
+    }
+
+    /// Creates a new temporary directory inside the specified path.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the temporary directory could not be created.
+    pub extern "Lua-C" fn temp_dir_in(path: &str) -> Result<lb_temp_dir> {
+        Ok(lb_temp_dir::new(tempfile::tempdir_in(path)?))
+    }
+}

crates/lb/src/fs/sync.rs

@@ -0,0 +1,251 @@
+use super::*;
+use luaffi::{cdef, metatype};
+use std::{
+    cell::RefCell,
+    fs::{DirEntry, FileType, Metadata, Permissions, ReadDir},
+    time::SystemTime,
+};
+
+/// Structure representing the type of a file with accessors for each file type.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_file_type(#[opaque] FileType);
+
+#[metatype]
+impl lb_file_type {
+    pub(super) fn new(ty: FileType) -> Self {
+        Self(ty)
+    }
+
+    /// Returns `true` if this file type is a directory.
+    pub extern "Lua-C" fn is_dir(&self) -> bool {
+        self.0.is_dir()
+    }
+
+    /// Returns `true` if this file type is a regular file.
+    pub extern "Lua-C" fn is_file(&self) -> bool {
+        self.0.is_file()
+    }
+
+    /// Returns `true` if this file type is a symbolic link.
+    pub extern "Lua-C" fn is_symlink(&self) -> bool {
+        self.0.is_file()
+    }
+
+    /// Returns the string `"file"` if this is a regular file, `"dir"` if this is a directory,
+    /// `"symlink"` if this is a symbolic link, or `"other"` if it is some other type of file.
+    #[tostring]
+    pub extern "Lua-C" fn tostring(&self) -> String {
+        if self.0.is_file() {
+            "file"
+        } else if self.0.is_dir() {
+            "dir"
+        } else if self.0.is_symlink() {
+            "symlink"
+        } else {
+            "other"
+        }
+        .into()
+    }
+}
+
+/// Metadata information about a file.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_file_meta(#[opaque] Metadata);
+
+#[metatype]
+impl lb_file_meta {
+    pub(super) fn new(meta: Metadata) -> Self {
+        Self(meta)
+    }
+
+    /// Returns `true` if this file is a directory.
+    pub extern "Lua-C" fn is_dir(&self) -> bool {
+        self.0.is_dir()
+    }
+
+    /// Returns `true` if this file is a regular file.
+    pub extern "Lua-C" fn is_file(&self) -> bool {
+        self.0.is_file()
+    }
+
+    /// Returns `true` if this file is a symbolic link.
+    pub extern "Lua-C" fn is_symlink(&self) -> bool {
+        self.0.is_file()
+    }
+
+    /// Returns the type of this file.
+    pub extern "Lua-C" fn r#type(&self) -> lb_file_type {
+        lb_file_type::new(self.0.file_type())
+    }
+
+    /// Returns the size of this file in bytes.
+    pub extern "Lua-C" fn size(&self) -> u64 {
+        self.0.len()
+    }
+
+    /// Returns the permissions of this file.
+    pub extern "Lua-C" fn perms(&self) -> lb_file_perms {
+        lb_file_perms::new(self.0.permissions())
+    }
+
+    /// Returns the creation time of this file as seconds since the Unix epoch.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the creation time could not be retrieved.
+    pub extern "Lua-C" fn created(&self) -> Result<f64> {
+        Ok(self
+            .0
+            .created()?
+            .duration_since(SystemTime::UNIX_EPOCH)
+            .map(|dur| dur.as_secs_f64())
+            .unwrap_or(0.))
+    }
+
+    /// Returns the modification time of this file as seconds since the Unix epoch.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the modification time could not be retrieved.
+    pub extern "Lua-C" fn modified(&self) -> Result<f64> {
+        Ok(self
+            .0
+            .modified()?
+            .duration_since(SystemTime::UNIX_EPOCH)
+            .map(|dur| dur.as_secs_f64())
+            .unwrap_or(0.))
+    }
+
+    /// Returns the last access time of this file as seconds since the Unix epoch.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the access time could not be retrieved.
+    pub extern "Lua-C" fn accessed(&self) -> Result<f64> {
+        Ok(self
+            .0
+            .accessed()?
+            .duration_since(SystemTime::UNIX_EPOCH)
+            .map(|dur| dur.as_secs_f64())
+            .unwrap_or(0.))
+    }
+
+    /// Returns a string representation of this file's metadata.
+    #[tostring]
+    pub extern "Lua-C" fn tostring(&self) -> String {
+        let ty = self.0.file_type();
+        if ty.is_file() {
+            format!("file {}", self.0.len())
+        } else if ty.is_dir() {
+            "dir".into()
+        } else if ty.is_symlink() {
+            "symlink".into()
+        } else {
+            "other".into()
+        }
+    }
+}
+
+/// Representation of the various permissions on a file.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_file_perms(#[opaque] RefCell<Permissions>);
+
+#[metatype]
+impl lb_file_perms {
+    pub(super) fn new(perms: Permissions) -> Self {
+        Self(RefCell::new(perms))
+    }
+
+    /// Returns `true` if the readonly flag is set.
+    pub extern "Lua-C" fn readonly(&self) -> bool {
+        self.0.borrow().readonly()
+    }
+
+    /// Sets the readonly flag.
+    pub extern "Lua-C" fn set_readonly(&self, readonly: bool) {
+        self.0.borrow_mut().set_readonly(readonly);
+    }
+}
+
+/// Synchronous version of [`lb_read_dir`].
+#[derive(Debug)]
+#[cdef]
+pub struct lb_read_dir_sync(#[opaque] RefCell<ReadDir>);
+
+#[metatype]
+impl lb_read_dir_sync {
+    pub(super) fn new(iter: ReadDir) -> Self {
+        Self(RefCell::new(iter))
+    }
+
+    /// Returns the next entry in the directory, or `nil` if there are no more entries.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the directory could not be read.
+    #[call]
+    pub extern "Lua-C" fn next(&self) -> Result<Option<lb_dir_entry_sync>> {
+        Ok(self
+            .0
+            .try_borrow_mut()?
+            .next()
+            .transpose()?
+            .map(lb_dir_entry_sync::new))
+    }
+}
+
+/// Synchronous version of [`lb_dir_entry`].
+#[derive(Debug)]
+#[cdef]
+pub struct lb_dir_entry_sync(#[opaque] DirEntry);
+
+#[metatype]
+impl lb_dir_entry_sync {
+    pub(super) fn new(entry: DirEntry) -> Self {
+        Self(entry)
+    }
+
+    /// Returns the full path of this entry.
+    pub extern "Lua-C" fn path(&self) -> String {
+        self.0.path().to_string_lossy().into()
+    }
+
+    /// Returns the file name of this entry.
+    pub extern "Lua-C" fn name(&self) -> String {
+        self.0.file_name().to_string_lossy().into()
+    }
+
+    /// Returns the type of this entry.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the file type could not be determined.
+    pub extern "Lua-C" fn r#type(&self) -> Result<lb_file_type> {
+        Ok(lb_file_type::new(self.0.file_type()?))
+    }
+
+    /// Returns the metadata for this entry.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the metadata could not be retrieved.
+    pub extern "Lua-C" fn metadata(&self) -> Result<lb_file_meta> {
+        Ok(lb_file_meta::new(self.0.metadata()?))
+    }
+
+    /// Returns the inode number for this entry.
+    #[cfg(unix)]
+    pub extern "Lua-C" fn ino(&self) -> u64 {
+        use std::os::unix::fs::DirEntryExt;
+        self.0.ino()
+    }
+
+    /// Returns the full path of this entry.
+    #[tostring]
+    pub extern "Lua" fn tostring(&self) -> String {
+        self.path()
+    }
+}

crates/lb/src/fs/temp.rs

@@ -0,0 +1,25 @@
+use luaffi::{cdef, metatype};
+use tempfile::TempDir;
+
+/// Directory in the filesystem that is automatically deleted when it is garbage-collected.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_temp_dir(#[opaque] TempDir);
+
+#[metatype]
+impl lb_temp_dir {
+    pub(super) fn new(dir: TempDir) -> Self {
+        Self(dir)
+    }
+
+    /// Returns the full path of this temporary directory.
+    pub extern "Lua-C" fn path(&self) -> String {
+        self.0.path().to_string_lossy().into()
+    }
+
+    /// Returns the full path of this temporary directory.
+    #[tostring]
+    pub extern "Lua" fn tostring(&self) -> String {
+        self.path()
+    }
+}

crates/lb/src/fs/walk.rs

@@ -0,0 +1,90 @@
+use super::*;
+use luaffi::{cdef, metatype};
+use std::cell::RefCell;
+use walkdir::{DirEntry, IntoIter};
+
+/// Iterator for recursively descending into a directory.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_walk_dir(#[opaque] RefCell<IntoIter>);
+
+#[metatype]
+impl lb_walk_dir {
+    pub(super) fn new(iter: IntoIter) -> Self {
+        Self(RefCell::new(iter))
+    }
+
+    /// Returns the next entry in the walk, or `nil` if there are no more entries.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the directory could not be read.
+    #[call]
+    pub extern "Lua-C" fn next(&self) -> Result<Option<lb_walk_dir_entry>> {
+        Ok(self
+            .0
+            .try_borrow_mut()?
+            .next()
+            .transpose()?
+            .map(lb_walk_dir_entry::new))
+    }
+}
+
+/// Entry inside of a directory on the filesystem obtained from [`lb_walk_dir`].
+#[derive(Debug)]
+#[cdef]
+pub struct lb_walk_dir_entry(#[opaque] DirEntry);
+
+#[metatype]
+impl lb_walk_dir_entry {
+    pub(super) fn new(entry: DirEntry) -> Self {
+        Self(entry)
+    }
+
+    /// Returns the full path of this entry.
+    pub extern "Lua-C" fn path(&self) -> String {
+        self.0.path().to_string_lossy().into()
+    }
+
+    /// Returns the file name of this entry.
+    pub extern "Lua-C" fn name(&self) -> String {
+        self.0.file_name().to_string_lossy().into()
+    }
+
+    /// Returns the type of this entry.
+    pub extern "Lua-C" fn r#type(&self) -> lb_file_type {
+        lb_file_type::new(self.0.file_type())
+    }
+
+    /// Returns the metadata for this entry.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw if the metadata could not be retrieved.
+    pub extern "Lua-C" fn metadata(&self) -> Result<lb_file_meta> {
+        Ok(lb_file_meta::new(self.0.metadata()?))
+    }
+
+    /// Returns `true` if this entry was created from a symbolic link.
+    pub extern "Lua-C" fn is_symlink(&self) -> bool {
+        self.0.path_is_symlink()
+    }
+
+    /// Returns the depth of this entry in the walk.
+    pub extern "Lua-C" fn depth(&self) -> u32 {
+        self.0.depth() as u32
+    }
+
+    /// Returns the inode number for this entry.
+    #[cfg(unix)]
+    pub extern "Lua-C" fn ino(&self) -> u64 {
+        use walkdir::DirEntryExt;
+        self.0.ino()
+    }
+
+    /// Returns the full path of this entry.
+    #[tostring]
+    pub extern "Lua" fn tostring(&self) -> String {
+        self.path()
+    }
+}

crates/lb/src/lib.rs

@@ -1,5 +1,11 @@
-pub mod channel;
+//! luby core libraries.
+#[cfg(feature = "fs")]
 pub mod fs;
+#[cfg(feature = "net")]
 pub mod net;
+#[cfg(feature = "runtime")]
 pub mod runtime;
+#[cfg(feature = "task")]
 pub mod task;
+#[cfg(feature = "time")]
+pub mod time;

crates/lb/src/net.rs

@@ -1,345 +0,0 @@
-//! The `lb:net` module provides an asynchronous network API for creating TCP or UDP servers and
-//! clients.
-//!
-//! See [`lb_libnet`] for items exported by this module.
-use derive_more::{From, FromStr};
-use luaffi::{cdef, metatype};
-use std::{
-    io,
-    net::{AddrParseError, IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr},
-};
-use tokio::net::{TcpListener, TcpSocket, TcpStream};
-
-/// Items exported by the `lb:net` module.
-///
-/// This module can be obtained by calling `require` in Lua.
-///
-/// ```lua
-/// local net = require("lb:net");
-/// ```
-#[cdef]
-pub struct lb_libnet;
-
-#[metatype]
-impl lb_libnet {
-    #[new]
-    extern "Lua-C" fn new() -> Self {
-        Self
-    }
-
-    /// See [`Ipv4Addr::LOCALHOST`].
-    pub extern "Lua-C" fn localhost_v4(&self) -> lb_ipaddr {
-        lb_ipaddr(Ipv4Addr::LOCALHOST.into())
-    }
-
-    /// See [`Ipv6Addr::LOCALHOST`].
-    pub extern "Lua-C" fn localhost_v6(&self) -> lb_ipaddr {
-        lb_ipaddr(Ipv6Addr::LOCALHOST.into())
-    }
-
-    /// See [`Ipv4Addr::UNSPECIFIED`].
-    pub extern "Lua-C" fn unspecified_v4(&self) -> lb_ipaddr {
-        lb_ipaddr(Ipv4Addr::UNSPECIFIED.into())
-    }
-
-    /// See [`Ipv6Addr::UNSPECIFIED`].
-    pub extern "Lua-C" fn unspecified_v6(&self) -> lb_ipaddr {
-        lb_ipaddr(Ipv6Addr::UNSPECIFIED.into())
-    }
-
-    /// See [`Ipv4Addr::BROADCAST`].
-    pub extern "Lua-C" fn broadcast_v4(&self) -> lb_ipaddr {
-        lb_ipaddr(Ipv4Addr::BROADCAST.into())
-    }
-
-    /// Creates an [`lb_ipaddr`] from the given input.
-    ///
-    /// If `s` is an [`lb_ipaddr`], a copy of that value is returned. If `s` is an
-    /// [`lb_socketaddr`], the IP address part of the socket address is returned. Otherwise, parses
-    /// `s` as an IP address string. Both IPv4 or IPv6 addresses are supported.
-    ///
-    /// # Errors
-    ///
-    /// Throws if `s` cannot be parsed as an IP address.
-    pub extern "Lua" fn ipaddr(&self, s: any) -> lb_ipaddr {
-        if __istype(__ct.lb_ipaddr, s) {
-            __new(__ct.lb_ipaddr, s) // copy constructor
-        } else if __istype(__ct.lb_socketaddr, s) {
-            s.ip()
-        } else {
-            self.__parse_ipaddr(s)
-        }
-    }
-
-    extern "Lua-C" fn __parse_ipaddr(&self, s: &str) -> Result<lb_ipaddr, AddrParseError> {
-        s.parse()
-    }
-
-    /// Creates an [`lb_socketaddr`] from the given input.
-    ///
-    /// A socket address is an IP address with a port number.
-    ///
-    /// If `s` is an [`lb_socketaddr`], a copy of that value is returned. If `s` is an
-    /// [`lb_ipaddr`], a socket address with that IP address is returned. Otherwise, parses `s` as a
-    /// socket address string. Both IPv4 and IPv6 addresses are supported.
-    ///
-    /// If `port` is not specified, `0` is used as the default.
-    ///
-    /// # Errors
-    ///
-    /// Throws if `s` cannot be parsed as an IP or socket address.
-    pub extern "Lua" fn socketaddr(&self, s: any, port: any) -> lb_socketaddr {
-        if port != () {
-            self.__new_socketaddr(self.ipaddr(s), port)
-        } else {
-            if __istype(__ct.lb_socketaddr, s) {
-                __new(__ct.lb_socketaddr, s) // copy constructor
-            } else if __istype(__ct.lb_ipaddr, s) {
-                self.__new_socketaddr(s, 0) // default port 0
-            } else {
-                self.__parse_socketaddr(s)
-            }
-        }
-    }
-
-    extern "Lua-C" fn __new_socketaddr(&self, ip: &lb_ipaddr, port: u16) -> lb_socketaddr {
-        SocketAddr::new(ip.0, port).into()
-    }
-
-    extern "Lua-C" fn __parse_socketaddr(&self, s: &str) -> Result<lb_socketaddr, AddrParseError> {
-        s.parse()
-    }
-
-    /// Creates a new TCP socket configured for IPv4.
-    ///
-    /// See [`TcpSocket::new_v4`].
-    ///
-    /// # Errors
-    ///
-    /// Throws if an error was encountered during the socket creation.
-    pub extern "Lua" fn tcp_v4(&self) -> lb_tcpsocket {
-        self.__new_tcp_v4()
-    }
-
-    /// Creates a new TCP socket configured for IPv6.
-    ///
-    /// See [`TcpSocket::new_v6`].
-    ///
-    /// # Errors
-    ///
-    /// Throws if an error was encountered during the socket creation.
-    pub extern "Lua" fn tcp_v6(&self) -> lb_tcpsocket {
-        self.__new_tcp_v6()
-    }
-
-    extern "Lua-C" fn __new_tcp_v4(&self) -> io::Result<lb_tcpsocket> {
-        TcpSocket::new_v4().map(lb_tcpsocket)
-    }
-
-    extern "Lua-C" fn __new_tcp_v6(&self) -> io::Result<lb_tcpsocket> {
-        TcpSocket::new_v6().map(lb_tcpsocket)
-    }
-}
-
-/// An IP address, either IPv4 or IPv6.
-///
-/// # Example
-///
-/// This example creates an [`lb_ipaddr`] by parsing an IP address string.
-///
-/// ```lua
-/// local net = require("lb:net");
-/// local addr = net:ipaddr("127.0.0.1"); -- ipv4 loopback address
-///
-/// assert(addr:is_v4());
-/// assert(addr:is_loopback());
-/// ```
-#[derive(Debug, Clone, Copy, PartialEq, Eq, From, FromStr)]
-#[cdef]
-pub struct lb_ipaddr(#[opaque] IpAddr);
-
-#[metatype]
-impl lb_ipaddr {
-    /// See [`IpAddr::is_unspecified`].
-    pub extern "Lua-C" fn is_unspecified(&self) -> bool {
-        self.0.is_unspecified()
-    }
-
-    /// See [`IpAddr::is_loopback`].
-    pub extern "Lua-C" fn is_loopback(&self) -> bool {
-        self.0.is_loopback()
-    }
-
-    /// See [`IpAddr::is_multicast`].
-    pub extern "Lua-C" fn is_multicast(&self) -> bool {
-        self.0.is_multicast()
-    }
-
-    /// Returns the string `"v4"` if this is an IPv4 address or `"v6"` if this is an IPv6 address.
-    pub extern "Lua" fn family(&self) -> string {
-        if self.is_v6() { "v6" } else { "v4" }
-    }
-
-    /// Returns `true` if this is an IPv4 address.
-    pub extern "Lua-C" fn is_v4(&self) -> bool {
-        self.0.is_ipv4()
-    }
-
-    /// See [`Ipv4Addr::is_private`].
-    pub extern "Lua-C" fn is_v4_private(&self) -> bool {
-        match self.0 {
-            IpAddr::V4(v4) => v4.is_private(),
-            IpAddr::V6(_) => false,
-        }
-    }
-
-    /// See [`Ipv4Addr::is_link_local`].
-    pub extern "Lua-C" fn is_v4_link_local(&self) -> bool {
-        match self.0 {
-            IpAddr::V4(v4) => v4.is_link_local(),
-            IpAddr::V6(_) => false,
-        }
-    }
-
-    /// See [`Ipv4Addr::is_broadcast`].
-    pub extern "Lua-C" fn is_v4_broadcast(&self) -> bool {
-        match self.0 {
-            IpAddr::V4(v4) => v4.is_broadcast(),
-            IpAddr::V6(_) => false,
-        }
-    }
-
-    /// See [`Ipv4Addr::is_documentation`].
-    pub extern "Lua-C" fn is_v4_documentation(&self) -> bool {
-        match self.0 {
-            IpAddr::V4(v4) => v4.is_documentation(),
-            IpAddr::V6(_) => false,
-        }
-    }
-
-    /// Returns `true` if this is an IPv6 address.
-    pub extern "Lua-C" fn is_v6(&self) -> bool {
-        self.0.is_ipv6()
-    }
-
-    /// See [`Ipv6Addr::is_unique_local`].
-    pub extern "Lua-C" fn is_v6_unique_local(&self) -> bool {
-        match self.0 {
-            IpAddr::V4(_) => false,
-            IpAddr::V6(v6) => v6.is_unique_local(),
-        }
-    }
-
-    /// See [`Ipv6Addr::is_unicast_link_local`].
-    pub extern "Lua-C" fn is_v6_unicast_link_local(&self) -> bool {
-        match self.0 {
-            IpAddr::V4(_) => false,
-            IpAddr::V6(v6) => v6.is_unicast_link_local(),
-        }
-    }
-
-    /// See [`Ipv4Addr::to_ipv6_compatible`].
-    pub extern "Lua-C" fn to_v6_compat(&self) -> Self {
-        match self.0 {
-            IpAddr::V4(v4) => Self(v4.to_ipv6_compatible().into()),
-            IpAddr::V6(_) => *self,
-        }
-    }
-
-    /// See [`Ipv4Addr::to_ipv6_mapped`].
-    pub extern "Lua-C" fn to_v6_mapped(&self) -> Self {
-        match self.0 {
-            IpAddr::V4(v4) => Self(v4.to_ipv6_mapped().into()),
-            IpAddr::V6(_) => *self,
-        }
-    }
-
-    /// See [`IpAddr::to_canonical`].
-    pub extern "Lua-C" fn canonical(&self) -> Self {
-        self.0.to_canonical().into()
-    }
-
-    /// Returns the string representation of this address.
-    #[tostring]
-    pub extern "Lua-C" fn tostring(&self) -> String {
-        self.0.to_string()
-    }
-}
-
-/// A socket address, which is an IP address with a port number.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, From, FromStr)]
-#[cdef]
-pub struct lb_socketaddr(#[opaque] SocketAddr);
-
-#[metatype]
-impl lb_socketaddr {
-    /// Returns the IP part of this address.
-    pub extern "Lua-C" fn ip(&self) -> lb_ipaddr {
-        self.0.ip().into()
-    }
-
-    /// Sets the IP part of this address.
-    ///
-    /// This function accepts the same arguments as [`ipaddr`](lb_libnet::ipaddr).
-    pub extern "Lua" fn set_ip(&mut self, s: any) -> &mut Self {
-        if __istype(__ct.lb_ipaddr, s) {
-            self.__set_ip(s);
-        } else if __istype(__ct.lb_socketaddr, s) {
-            self.__set_ip(s.ip());
-        } else {
-            self.__set_ip_parse(s);
-        }
-        self
-    }
-
-    extern "Lua-C" fn __set_ip(&mut self, ip: &lb_ipaddr) {
-        self.0.set_ip(ip.0);
-    }
-
-    extern "Lua-C" fn __set_ip_parse(&mut self, s: &str) -> Result<(), AddrParseError> {
-        s.parse().map(|ip| self.0.set_ip(ip))
-    }
-
-    /// Returns the port part of this address.
-    pub extern "Lua-C" fn port(&self) -> u16 {
-        self.0.port()
-    }
-
-    /// Sets the port part of this address.
-    pub extern "Lua" fn set_port(&mut self, port: number) -> &mut Self {
-        self.__set_port(port);
-        self
-    }
-
-    extern "Lua-C" fn __set_port(&mut self, port: u16) {
-        self.0.set_port(port)
-    }
-
-    /// Returns the string representation of this address.
-    #[tostring]
-    pub extern "Lua-C" fn tostring(&self) -> String {
-        self.0.to_string()
-    }
-}
-
-/// A TCP socket which has not yet been converted to a [`lb_tcpstream`] or [`lb_tcplistener`].
-#[derive(Debug, From)]
-#[cdef]
-pub struct lb_tcpsocket(#[opaque] TcpSocket);
-
-#[metatype]
-impl lb_tcpsocket {}
-
-#[derive(Debug, From)]
-#[cdef]
-pub struct lb_tcpstream(#[opaque] TcpStream);
-
-#[metatype]
-impl lb_tcpstream {}
-
-#[derive(Debug, From)]
-#[cdef]
-pub struct lb_tcplistener(#[opaque] TcpListener);
-
-#[metatype]
-impl lb_tcplistener {}

crates/lb/src/net/mod.rs

@@ -0,0 +1,588 @@
+//! Network library.
+//!
+//! The `lb:net` library provides an asynchronous network API for woring with TCP, UDP and IPC
+//! sockets.
+//!
+//! ## Exports
+//!
+//! See [`lb_netlib`] for items exported by this library.
+use derive_more::{From, FromStr};
+use luaffi::{cdef, marker::OneOf, metatype};
+use std::{
+    cell::{BorrowError, BorrowMutError},
+    net::{AddrParseError, IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr},
+};
+use thiserror::Error;
+use tokio::net::TcpSocket;
+
+mod tcp;
+
+pub use tcp::*;
+
+/// Errors that can be thrown by this library.
+///
+/// Functions which return this error will **throw**. The error message can be caught by using
+/// [`pcall(f, ...)`](https://www.lua.org/manual/5.1/manual.html#pdf-pcall).
+#[derive(Debug, Error)]
+pub enum Error {
+    /// Attempt to access an object while it is being modified.
+    #[error("cannot access object while it is being modified")]
+    Borrow(#[from] BorrowError),
+    /// Attempt to modify an object while it is in use.
+    #[error("cannot modify object while it is in use")]
+    BorrowMut(#[from] BorrowMutError),
+    /// I/O error.
+    #[error("{0}")]
+    Io(#[from] std::io::Error),
+    /// IP or socket address syntax error.
+    #[error("{0}")]
+    InvalidAddr(#[from] AddrParseError),
+    /// Socket was already converted and can no longer be used.
+    #[error("socket was already converted")]
+    SocketConsumed,
+    /// Socket was closed and can no longer be used.
+    #[error("socket was closed")]
+    SocketClosed,
+    /// Specified socket half was not `"read"` or `"write"`.
+    #[error("invalid socket half")]
+    InvalidSocketHalf,
+}
+
+type Result<T> = std::result::Result<T, Error>;
+
+/// Items exported by the `lb:net` library.
+///
+/// This library can be acquired by calling
+/// [`require("lb:net")`](https://www.lua.org/manual/5.1/manual.html#pdf-require).
+///
+/// ```lua
+/// local net = require("lb:net")
+/// ```
+#[cdef(module = "lb:net")]
+pub struct lb_netlib;
+
+#[metatype]
+impl lb_netlib {
+    #[new]
+    extern "Lua-C" fn new() -> Self {
+        Self
+    }
+
+    /// An IPv4 address representing localhost: `127.0.0.1`
+    pub extern "Lua-C" fn localhost() -> lb_ipaddr {
+        lb_ipaddr(Ipv4Addr::LOCALHOST.into())
+    }
+
+    /// An IPv6 address representing localhost: `::1`
+    pub extern "Lua-C" fn localhost_v6() -> lb_ipaddr {
+        lb_ipaddr(Ipv6Addr::LOCALHOST.into())
+    }
+
+    /// An IPv4 address representing an unspecified address: `0.0.0.0`
+    pub extern "Lua-C" fn unspecified() -> lb_ipaddr {
+        lb_ipaddr(Ipv4Addr::UNSPECIFIED.into())
+    }
+
+    /// An IPv6 address representing an unspecified address: `::`
+    pub extern "Lua-C" fn unspecified_v6() -> lb_ipaddr {
+        lb_ipaddr(Ipv6Addr::UNSPECIFIED.into())
+    }
+
+    /// An IPv4 address representing the broadcast address: `255.255.255.255`
+    pub extern "Lua-C" fn broadcast() -> lb_ipaddr {
+        lb_ipaddr(Ipv4Addr::BROADCAST.into())
+    }
+
+    /// Creates an IP address from the given input.
+    ///
+    /// If `addr` is an [`lb_ipaddr`], a copy of that value is returned. If `addr` is an
+    /// [`lb_socketaddr`], the IP part of the socket address is returned. Otherwise, parses `addr`
+    /// as an IP address string. Both IPv4 and IPv6 addresses are accepted.
+    ///
+    /// An address string may be something like `127.0.0.1`.
+    ///
+    /// The type of the parsed address can be checked using [`is_v4`](lb_ipaddr::is_v4) or
+    /// [`is_v6`](lb_ipaddr::is_v6) functions on the returned [`lb_ipaddr`](lb_ipaddr) value.
+    ///
+    /// # Errors
+    ///
+    /// This function will throw an error if the input syntax is invalid.
+    ///
+    /// # Example
+    ///
+    /// ```lua
+    /// local net = require("lb:net")
+    /// local addr = net.ipaddr("192.168.1.1")
+    ///
+    /// assert(addr:is_v4())
+    /// ```
+    pub extern "Lua" fn ipaddr(
+        addr: OneOf<(&str, &lb_ipaddr, &lb_socketaddr)>,
+    ) -> Result<lb_ipaddr> {
+        if __istype(__ct.lb_ipaddr, addr) {
+            __new(__ct.lb_ipaddr, addr) // copy constructor
+        } else if __istype(__ct.lb_socketaddr, addr) {
+            s.ip()
+        } else {
+            Self::__parse_ipaddr(addr)
+        }
+    }
+
+    extern "Lua-C" fn __parse_ipaddr(addr: &str) -> Result<lb_ipaddr> {
+        Ok(addr.parse()?)
+    }
+
+    /// Creates a socket address from the given input.
+    ///
+    /// A socket address is an IP address with a prescribed port number.
+    ///
+    /// If `addr` is an [`lb_socketaddr`], a copy of that value is returned. If `addr` is an
+    /// [`lb_ipaddr`], a socket address with that IP part is returned. Otherwise, parses `addr` as a
+    /// socket address string. Both IPv4 and IPv6 addresses are accepted.
+    ///
+    /// If `port` is specified, it is always used as the port part of the returned socket address.
+    /// Otherwise, `0` is used as the default.
+    ///
+    /// An address string may be something like `127.0.0.1:3000`.
+    ///
+    /// # Errors
+    ///
+    /// This function will throw an error if the input syntax is invalid.
+    ///
+    /// # Example
+    ///
+    /// ```lua
+    /// local net = require("lb:net")
+    /// local addr = net.socketaddr("::1", 8080)
+    ///
+    /// assert(addr:ip():is_v6() and addr:ip():is_loopback())
+    /// assert(addr:port() == 8080)
+    /// ```
+    pub extern "Lua" fn socketaddr(
+        addr: OneOf<(&str, &lb_ipaddr, &lb_socketaddr)>,
+        port: Option<u16>,
+    ) -> Result<lb_socketaddr> {
+        if port != () {
+            Self::__new_skaddr(Self::ipaddr(addr), port)
+        } else {
+            if __istype(__ct.lb_socketaddr, addr) {
+                __new(__ct.lb_socketaddr, addr) // copy constructor
+            } else if __istype(__ct.lb_ipaddr, addr) {
+                Self::__new_skaddr(addr, 0) // default port 0
+            } else {
+                Self::__parse_skaddr(addr)
+            }
+        }
+    }
+
+    extern "Lua-C" fn __new_skaddr(ip: &lb_ipaddr, port: u16) -> lb_socketaddr {
+        SocketAddr::new(ip.0, port).into()
+    }
+
+    extern "Lua-C" fn __parse_skaddr(addr: &str) -> Result<lb_socketaddr> {
+        Ok(if let Ok(addr) = addr.parse() {
+            SocketAddr::new(addr, 0).into() // default port 0
+        } else {
+            addr.parse::<SocketAddr>()?.into()
+        })
+    }
+
+    /// Creates a new TCP socket configured for IPv4.
+    ///
+    /// This calls `socket(2)` with `AF_INET` and `SOCK_STREAM`.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw an error if the socket could not be created.
+    pub extern "Lua-C" fn tcp() -> Result<lb_tcpsocket> {
+        Ok(lb_tcpsocket::new(TcpSocket::new_v4()?))
+    }
+
+    /// Creates a new TCP socket configured for IPv6.
+    ///
+    /// This calls `socket(2)` with `AF_INET6` and `SOCK_STREAM`.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw an error if the socket could not be created.
+    pub extern "Lua-C" fn tcp_v6() -> Result<lb_tcpsocket> {
+        Ok(lb_tcpsocket::new(TcpSocket::new_v6()?))
+    }
+
+    /// Creates a new TCP socket bound to the given address and port.
+    ///
+    /// This function accepts the same arguments as [`socketaddr`](Self::socketaddr). It creates a
+    /// new TCP socket configured to use either IPv4 or IPv6 depending on the type of the given
+    /// address, and binds it to that address.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw an error if the socket could not be created or bound to the
+    /// specified address.
+    ///
+    /// # Example
+    ///
+    /// ```lua
+    /// local net = require("lb:net")
+    /// local socket = net.bind_tcp("127.0.0.1")
+    ///
+    /// assert(socket:local_addr():ip() == net.ipaddr("127.0.0.1"))
+    /// socket:set_nodelay(true)
+    /// ```
+    pub extern "Lua" fn bind_tcp(
+        addr: OneOf<(&str, &lb_ipaddr, &lb_socketaddr)>,
+        port: Option<u16>,
+    ) -> Result<lb_tcpsocket> {
+        let addr = Self::socketaddr(addr, port);
+        let socket;
+        if addr.ip().is_v6() {
+            socket = Self::tcp_v6();
+        } else {
+            socket = Self::tcp();
+        }
+        socket.bind(addr);
+        socket
+    }
+
+    /// Creates a new TCP socket listening on the given address and port.
+    ///
+    /// This is a convenience function that combines [`bind_tcp`](Self::bind_tcp) and
+    /// [`listen`](lb_tcpsocket::listen). It accepts the same arguments as
+    /// [`socketaddr`](Self::socketaddr).
+    ///
+    /// # Errors
+    ///
+    /// This function may throw an error if the socket could not be created, bound to the specified
+    /// address, or could not transition to the listening state.
+    ///
+    /// # Example
+    ///
+    /// ```lua,no_run
+    /// local net = require("lb:net")
+    /// local listener = net.listen_tcp("127.0.0.1")
+    ///
+    /// assert(listener:local_addr():ip() == net.ipaddr("127.0.0.1"))
+    ///
+    /// for stream in listener do
+    ///     print("client connected: ", stream:peer_addr())
+    /// end
+    /// ```
+    pub extern "Lua" fn listen_tcp(
+        addr: OneOf<(&str, &lb_ipaddr, &lb_socketaddr)>,
+        port: Option<u16>,
+    ) -> Result<lb_tcplistener> {
+        Self::bind_tcp(addr, port).listen(1024)
+    }
+
+    /// Establishes a new TCP connection to the server at the given address and port.
+    ///
+    /// This function accepts the same arguments as [`socketaddr`](Self::socketaddr). It creates a
+    /// new TCP socket and connects it to the specified address.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw an error if the socket could not be created or connected to the
+    /// specified address.
+    ///
+    /// # Example
+    ///
+    /// ```lua
+    /// local net = require("lb:net")
+    /// local listener = net.listen_tcp("127.0.0.1")
+    /// local stream = net.connect_tcp("127.0.0.1", listener:local_addr():port())
+    ///
+    /// assert(stream:peer_addr():ip() == net.ipaddr("127.0.0.1"))
+    /// stream:write("Hello, server!\n")
+    /// ```
+    pub async extern "Lua" fn connect_tcp(
+        addr: OneOf<(&str, &lb_ipaddr, &lb_socketaddr)>,
+        port: Option<u16>,
+    ) -> Result<lb_tcpstream> {
+        let addr = Self::socketaddr(addr, port);
+        let socket;
+        if addr.ip().is_v6() {
+            socket = Self::tcp_v6();
+        } else {
+            socket = Self::tcp();
+        }
+        socket.connect(addr)
+    }
+}
+
+/// IP address, either IPv4 or IPv6.
+///
+/// # Example
+///
+/// This example creates an [`lb_ipaddr`] by parsing an IP address string.
+///
+/// ```lua
+/// local net = require("lb:net")
+/// local addr = net.ipaddr("127.0.0.1") -- ipv4 loopback address
+///
+/// assert(addr:is_v4() and addr:is_loopback())
+/// assert(tostring(addr) == "127.0.0.1")
+/// ```
+#[derive(Debug, Clone, Copy, PartialEq, Eq, From, FromStr)]
+#[cdef]
+pub struct lb_ipaddr(#[opaque] IpAddr);
+
+#[metatype]
+impl lb_ipaddr {
+    /// Returns `true` if this is an IPv4 address.
+    pub extern "Lua-C" fn is_v4(&self) -> bool {
+        self.0.is_ipv4()
+    }
+
+    /// Returns `true` if this is an IPv6 address.
+    pub extern "Lua-C" fn is_v6(&self) -> bool {
+        self.0.is_ipv6()
+    }
+
+    /// Returns the string `"v4"` if this is an IPv4 address, or `"v6"` if this is an IPv6 address.
+    pub extern "Lua" fn family(&self) -> String {
+        if self.is_v6() { "v6" } else { "v4" }
+    }
+
+    /// Returns `true` if this is a loopback address.
+    ///
+    /// For IPv4, this is any address in the `127.0.0.0/8` range.
+    ///
+    /// For IPv6, this is the address `::1`.
+    pub extern "Lua-C" fn is_loopback(&self) -> bool {
+        self.0.is_loopback()
+    }
+
+    /// Returns `true` if this address is unspecified.
+    ///
+    /// For IPv4, this is the address `0.0.0.0`.
+    ///
+    /// For IPv6, this is the address `::`.
+    pub extern "Lua-C" fn is_unspecified(&self) -> bool {
+        self.0.is_unspecified()
+    }
+
+    /// Returns `true` if this address is a multicast address.
+    ///
+    /// For IPv4, this is any address in the `224.0.0.0/4` range.
+    ///
+    /// For IPv6, this is any address in the `ff00::/8` range.
+    pub extern "Lua-C" fn is_multicast(&self) -> bool {
+        self.0.is_multicast()
+    }
+
+    /// Returns `true` if this is an IPv4 private address.
+    ///
+    /// For IPv4, this is any address in one of these ranges:
+    ///
+    /// - `10.0.0.0/8`
+    /// - `172.16.0.0/12`
+    /// - `192.168.0.0/16`
+    ///
+    /// For IPv6, this always returns `false`.
+    pub extern "Lua-C" fn is_v4_private(&self) -> bool {
+        match self.0 {
+            IpAddr::V4(v4) => v4.is_private(),
+            IpAddr::V6(_) => false,
+        }
+    }
+
+    /// Returns `true` if this is an IPv4 link-local address.
+    ///
+    /// For IPv4, this is any address in the `169.254.0.0/16` range.
+    ///
+    /// For IPv6, this always returns `false`.
+    pub extern "Lua-C" fn is_v4_link_local(&self) -> bool {
+        match self.0 {
+            IpAddr::V4(v4) => v4.is_link_local(),
+            IpAddr::V6(_) => false,
+        }
+    }
+
+    /// Returns `true` if this is an IPv4 broadcast address.
+    ///
+    /// For IPv4, this is the address `255.255.255.255`.
+    ///
+    /// For IPv6, this always returns `false`.
+    pub extern "Lua-C" fn is_v4_broadcast(&self) -> bool {
+        match self.0 {
+            IpAddr::V4(v4) => v4.is_broadcast(),
+            IpAddr::V6(_) => false,
+        }
+    }
+
+    /// Returns `true` if this is an IPv4 documentation address.
+    ///
+    /// For IPv4, this is any address in one of these ranges:
+    ///
+    /// - `192.0.2.0/24` (TEST-NET-1)
+    /// - `198.51.100.0/24` (TEST-NET-2)
+    /// - `203.0.113.0/24` (TEST-NET-3)
+    ///
+    /// For IPv6, this always returns `false`.
+    pub extern "Lua-C" fn is_v4_documentation(&self) -> bool {
+        match self.0 {
+            IpAddr::V4(v4) => v4.is_documentation(),
+            IpAddr::V6(_) => false,
+        }
+    }
+
+    /// Returns `true` if this is an IPv6 unique local address.
+    ///
+    /// For IPv4, this always returns `false`.
+    ///
+    /// For IPv6, this is any address in the `fc00::/7` range.
+    pub extern "Lua-C" fn is_v6_unique_local(&self) -> bool {
+        match self.0 {
+            IpAddr::V4(_) => false,
+            IpAddr::V6(v6) => v6.is_unique_local(),
+        }
+    }
+
+    /// Returns `true` if this is an IPv6 unicast address with link-local scope.
+    ///
+    /// For IPv4, this always returns `false`.
+    ///
+    /// For IPv6, this is any address in the `fe80::/10` range.
+    pub extern "Lua-C" fn is_v6_unicast_link_local(&self) -> bool {
+        match self.0 {
+            IpAddr::V4(_) => false,
+            IpAddr::V6(v6) => v6.is_unicast_link_local(),
+        }
+    }
+
+    /// Converts this address to IPv4.
+    ///
+    /// For IPv4, this returns the address unchanged.
+    ///
+    /// For IPv6, this returns the original IPv4 address if it is an IPv4-mapped or IPv4-compatible
+    /// IPv6 address. Otherwise, this returns `nil`.
+    pub extern "Lua-C" fn to_v4(&self) -> Option<Self> {
+        match self.0 {
+            IpAddr::V4(_) => Some(*self),
+            IpAddr::V6(v6) => v6.to_ipv4().map(|v| Self(v.into())),
+        }
+    }
+
+    /// Converts this address to IPv6.
+    ///
+    /// For IPv4, this returns the IPv4-mapped IPv6 address as defined by
+    /// [`Ipv4Addr::to_ipv6_mapped`].
+    ///
+    /// For IPv6, this returns the address unchanged.
+    pub extern "Lua-C" fn to_v6(&self) -> Self {
+        match self.0 {
+            IpAddr::V4(v4) => Self(v4.to_ipv6_mapped().into()),
+            IpAddr::V6(_) => *self,
+        }
+    }
+
+    /// Returns the canonical form of this address.
+    ///
+    /// For IPv4, this returns the address unchanged.
+    ///
+    /// For IPv6, this returns the original IPv4 address if it is an IPv4-mapped or IPv4-compatible
+    /// IPv6 address. Otherwise, this returns the address unchanged.
+    pub extern "Lua-C" fn to_canonical(&self) -> Self {
+        match self.0 {
+            IpAddr::V4(_) => *self,
+            IpAddr::V6(v6) => v6.to_ipv4().map_or(*self, |v| Self(v.into())),
+        }
+    }
+
+    /// Returns `true` if the given addresses are equal.
+    ///
+    /// Two addresses are considered equal if they are of the same family (IPv4 or IPv6) and
+    /// represent the same address in octets.
+    #[eq]
+    pub extern "Lua-C" fn equals(left: &Self, right: &Self) -> bool {
+        left.0 == right.0
+    }
+
+    /// Returns `true` if the left address is less than the right address.
+    ///
+    /// IPv4 addresses are always less than IPv6 addresses.
+    #[lt]
+    pub extern "Lua-C" fn less_than(left: &Self, right: &Self) -> bool {
+        left.0 < right.0
+    }
+
+    /// Returns `true` if the left address is less than or equal to the right address.
+    ///
+    /// IPv4 addresses are always less than IPv6 addresses.
+    #[le]
+    pub extern "Lua-C" fn less_than_or_equals(left: &Self, right: &Self) -> bool {
+        left.0 <= right.0
+    }
+
+    /// Returns the string representation of this address.
+    #[tostring]
+    pub extern "Lua-C" fn tostring(&self) -> String {
+        self.0.to_string()
+    }
+}
+
+/// Socket address, which is an IP address with a port number.
+///
+/// This represents an IP address with a prescribed port, such as `127.0.0.1:8080` or `[::1]:443`.
+/// It is used to specify endpoints for network connections and listeners, and can be constructed by
+/// [`socketaddr`](lb_netlib::socketaddr).
+///
+/// # Example
+///
+/// ```lua
+/// local net = require("lb:net")
+/// local addr = net.socketaddr("127.0.0.1:8080")
+///
+/// assert(addr:ip() == net.ipaddr("127.0.0.1") and addr:port() == 8080)
+/// assert(tostring(addr) == "127.0.0.1:8080")
+/// ```
+#[derive(Debug, Clone, Copy, PartialEq, Eq, From, FromStr)]
+#[cdef]
+pub struct lb_socketaddr(#[opaque] SocketAddr);
+
+#[metatype]
+impl lb_socketaddr {
+    /// The IP part of this address.
+    pub extern "Lua-C" fn ip(&self) -> lb_ipaddr {
+        self.0.ip().into()
+    }
+
+    /// The port part of this address.
+    pub extern "Lua-C" fn port(&self) -> u16 {
+        self.0.port()
+    }
+
+    /// Returns a new socket address with the given IP address and the same port.
+    pub extern "Lua-C" fn with_ip(&self, ip: &lb_ipaddr) -> Self {
+        SocketAddr::new(ip.0, self.port()).into()
+    }
+
+    /// Returns a new socket address with the given port and the same IP address.
+    pub extern "Lua-C" fn with_port(&self, port: u16) -> Self {
+        SocketAddr::new(self.ip().0, port).into()
+    }
+
+    /// Returns `true` if the given addresses are equal.
+    #[eq]
+    pub extern "Lua-C" fn equals(left: &Self, right: &Self) -> bool {
+        left.0 == right.0
+    }
+
+    /// Returns `true` if the left address is less than the right address.
+    #[lt]
+    pub extern "Lua-C" fn less_than(left: &Self, right: &Self) -> bool {
+        left.0 < right.0
+    }
+
+    /// Returns `true` if the left address is less than or equal to the right address.
+    #[le]
+    pub extern "Lua-C" fn less_than_or_equals(left: &Self, right: &Self) -> bool {
+        left.0 <= right.0
+    }
+
+    /// Returns the string representation of this address.
+    #[tostring]
+    pub extern "Lua-C" fn tostring(&self) -> String {
+        self.0.to_string()
+    }
+}

crates/lb/src/net/tcp.rs

@@ -0,0 +1,622 @@
+use super::*;
+use luaffi::{cdef, marker::fun, metatype};
+use luajit::LUA_NOREF;
+use std::io::ErrorKind;
+use std::{
+    cell::{Ref, RefCell, RefMut},
+    ffi::c_int,
+    time::Duration,
+};
+use tokio::net::tcp::{OwnedReadHalf, OwnedWriteHalf};
+use tokio::{
+    io::{AsyncReadExt, AsyncWriteExt, Interest},
+    net::{TcpListener, TcpSocket, TcpStream},
+};
+
+/// TCP socket which has not yet been converted to an [`lb_tcpstream`] or [`lb_tcplistener`].
+///
+/// This type represents a TCP socket in its initial state, before it is connected or set to listen.
+/// It can be configured (e.g., socket options, bind address) before being converted to an
+/// [`lb_tcpstream`] (via [`connect`](lb_tcpsocket::connect)) or [`lb_tcplistener`] (via
+/// [`listen`](lb_tcpsocket::listen)), after which it can no longer be used.
+///
+/// Methods on this type may fail if the operating system does not support the requested operation.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_tcpsocket(#[opaque] RefCell<Option<TcpSocket>>);
+
+#[metatype]
+impl lb_tcpsocket {
+    pub(super) fn new(socket: TcpSocket) -> Self {
+        Self(RefCell::new(Some(socket)))
+    }
+
+    fn socket<'s>(&'s self) -> Result<Ref<'s, TcpSocket>> {
+        let socket = self.0.borrow();
+        match *socket {
+            Some(_) => Ok(Ref::map(socket, |s| s.as_ref().unwrap())),
+            None => Err(Error::SocketConsumed),
+        }
+    }
+
+    /// Gets the value of the `SO_KEEPALIVE` option on this socket.
+    pub extern "Lua-C" fn keepalive(&self) -> Result<bool> {
+        Ok(self.socket()?.keepalive()?)
+    }
+
+    /// Sets value for the `SO_KEEPALIVE` option on this socket.
+    ///
+    /// This enables or disables periodic keepalive messages on the connection.
+    pub extern "Lua-C" fn set_keepalive(&self, enabled: bool) -> Result<()> {
+        Ok(self.socket()?.set_keepalive(enabled)?)
+    }
+
+    /// Gets the value of the `SO_REUSEADDR` option on this socket.
+    pub extern "Lua-C" fn reuseaddr(&self) -> Result<bool> {
+        Ok(self.socket()?.reuseaddr()?)
+    }
+
+    /// Sets value for the `SO_REUSEADDR` option on this socket.
+    ///
+    /// This allows the socket to bind to an address that is already in use.
+    pub extern "Lua-C" fn set_reuseaddr(&self, enabled: bool) -> Result<()> {
+        Ok(self.socket()?.set_reuseaddr(enabled)?)
+    }
+
+    /// Gets the value of the `SO_REUSEPORT` option on this socket.
+    pub extern "Lua-C" fn reuseport(&self) -> Result<bool> {
+        Ok(self.socket()?.reuseport()?)
+    }
+
+    /// Sets value for the `SO_REUSEPORT` option on this socket.
+    ///
+    /// This allows multiple sockets to bind to the same port.
+    pub extern "Lua-C" fn set_reuseport(&self, enabled: bool) -> Result<()> {
+        Ok(self.socket()?.set_reuseport(enabled)?)
+    }
+
+    /// Gets the value of the `SO_SNDBUF` option on this socket.
+    pub extern "Lua-C" fn sendbuf(&self) -> Result<u32> {
+        Ok(self.socket()?.send_buffer_size()?)
+    }
+
+    /// Sets value for the `SO_SNDBUF` option on this socket.
+    ///
+    /// This sets the size of the send buffer in bytes.
+    pub extern "Lua-C" fn set_sendbuf(&self, size: u32) -> Result<()> {
+        Ok(self.socket()?.set_send_buffer_size(size)?)
+    }
+
+    /// Gets the value of the `SO_RCVBUF` option on this socket.
+    pub extern "Lua-C" fn recvbuf(&self) -> Result<u32> {
+        Ok(self.socket()?.recv_buffer_size()?)
+    }
+
+    /// Sets value for the `SO_RCVBUF` option on this socket.
+    ///
+    /// This sets the size of the receive buffer in bytes.
+    pub extern "Lua-C" fn set_recvbuf(&self, size: u32) -> Result<()> {
+        Ok(self.socket()?.set_recv_buffer_size(size)?)
+    }
+
+    /// Gets the value of the `SO_LINGER` option on this socket, in seconds.
+    pub extern "Lua-C" fn linger(&self) -> Result<f64> {
+        Ok(self
+            .socket()?
+            .linger()?
+            .map(|n| n.as_secs_f64())
+            .unwrap_or(0.))
+    }
+
+    /// Sets the value of the `SO_LINGER` option on this socket.
+    ///
+    /// This controls how long the socket will remain open after close if unsent data is present.
+    pub extern "Lua-C" fn set_linger(&self, secs: f64) -> Result<()> {
+        let secs = secs.max(0.);
+        Ok(self
+            .socket()?
+            .set_linger((secs != 0.).then_some(Duration::from_secs_f64(secs)))?)
+    }
+
+    /// Gets the value of the `TCP_NODELAY` option on this socket.
+    pub extern "Lua-C" fn nodelay(&self) -> Result<bool> {
+        Ok(self.socket()?.nodelay()?)
+    }
+
+    /// Sets the value of the `TCP_NODELAY` option on this socket.
+    ///
+    /// This enables or disables Nagle's algorithm, which delays sending small packets.
+    pub extern "Lua-C" fn set_nodelay(&self, enabled: bool) -> Result<()> {
+        Ok(self.socket()?.set_nodelay(enabled)?)
+    }
+
+    /// Gets the local address that this socket is bound to.
+    pub extern "Lua-C" fn local_addr(&self) -> Result<lb_socketaddr> {
+        Ok(self.socket()?.local_addr()?.into())
+    }
+
+    /// Binds this socket to the given local address.
+    pub extern "Lua-C" fn bind(&self, addr: &lb_socketaddr) -> Result<()> {
+        Ok(self.socket()?.bind(addr.0)?)
+    }
+
+    /// Transitions this socket to the listening state.
+    ///
+    /// This consumes the socket and returns a new [`lb_tcplistener`] that can accept incoming
+    /// connections. This socket object can no longer be used after this call.
+    pub extern "Lua-C" fn listen(&self, backlog: u32) -> Result<lb_tcplistener> {
+        let socket = self.0.borrow_mut().take().ok_or(Error::SocketConsumed)?;
+        Ok(lb_tcplistener::new(socket.listen(backlog)?))
+    }
+
+    /// Connects this socket to the given remote socket address, transitioning it to an established
+    /// state.
+    ///
+    /// This consumes the socket and returns a new [`lb_tcpstream`] that can be used to send and
+    /// receive data. This socket object can no longer be used after this call.
+    ///
+    /// # Errors
+    ///
+    /// This function may throw an error if connection could not be established to the given remote
+    /// address.
+    pub async extern "Lua-C" fn connect(&self, addr: &lb_socketaddr) -> Result<lb_tcpstream> {
+        let socket = self.0.borrow_mut().take().ok_or(Error::SocketConsumed)?;
+        Ok(lb_tcpstream::new(socket.connect(addr.0).await?))
+    }
+}
+
+/// TCP connection between a local and a remote socket.
+///
+/// This represents an established TCP connection. It is created by connecting an [`lb_tcpsocket`]
+/// to a remote socket (via [`connect`](lb_tcpsocket::connect)) or accepting a connection from an
+/// [`lb_tcplistener`] (via [`accept`](lb_tcplistener::accept)). It provides methods for reading
+/// from and writing to the stream asynchronously.
+///
+/// The stream supports reading and writing data in both directions concurrently. Typically you
+/// would spawn one reader task and one writer task to handle incoming and outgoing data
+/// respectively. Connection is closed when this object goes out of scope and gets garbage
+/// collected, or when [`close`](Self::close) is explicitly called.
+///
+/// Methods on this type may fail if the operating system does not support the requested operation.
+///
+/// # Example
+///
+/// This examples spawns a reader task and a writer task to operate on the stream concurrently.
+///
+/// ```lua,no_run
+/// local task = require("lb:task")
+/// local net = require("lb:net")
+/// local socket = net.connect_tcp("127.0.0.1:1234")
+///
+/// print("local address: ", socket:local_addr())
+/// print("remote address: ", socket:peer_addr())
+///
+/// local reader = spawn(function()
+///     for chunk in socket, 1024 do
+///         print("received: ", chunk)
+///     end
+///
+///     print("done reading")
+/// end)
+///
+/// local writer = spawn(function()
+///     for i = 1, 10 do
+///         local msg = ("message %d"):format(i)
+///         socket:write(msg)
+///         print("sent: ", msg)
+///     end
+///
+///     print("done writing")
+/// end)
+///
+/// task.join(reader, writer)
+/// ```
+///
+/// The above example uses the socket as an iterator in a generic `for` loop to read data in chunks
+/// of up to 1024 bytes. It is equivalent to the following:
+///
+/// ```lua,no_run
+/// local net = require("lb:net")
+/// local socket = net.connect_tcp("127.0.0.1:1234")
+///
+/// while true do
+///     local chunk = socket:read_partial(1024)
+///     if chunk == nil then break end
+///     print("received: ", chunk)
+/// end
+/// ```
+#[derive(Debug)]
+#[cdef]
+pub struct lb_tcpstream {
+    #[opaque]
+    read: RefCell<Option<OwnedReadHalf>>,
+    #[opaque]
+    write: RefCell<Option<OwnedWriteHalf>>,
+}
+
+#[metatype]
+impl lb_tcpstream {
+    pub(super) fn new(stream: TcpStream) -> Self {
+        let (read, write) = stream.into_split();
+        Self {
+            read: RefCell::new(Some(read)),
+            write: RefCell::new(Some(write)),
+        }
+    }
+
+    fn read_half<'s>(&'s self) -> Result<RefMut<'s, OwnedReadHalf>> {
+        let read = self.read.try_borrow_mut()?;
+        match *read {
+            Some(_) => Ok(RefMut::map(read, |s| s.as_mut().unwrap())),
+            None => Err(Error::SocketClosed),
+        }
+    }
+
+    fn write_half<'s>(&'s self) -> Result<RefMut<'s, OwnedWriteHalf>> {
+        let write = self.write.try_borrow_mut()?;
+        match *write {
+            Some(_) => Ok(RefMut::map(write, |s| s.as_mut().unwrap())),
+            None => Err(Error::SocketClosed),
+        }
+    }
+
+    /// The local socket address that this stream is bound to.
+    pub extern "Lua-C" fn local_addr(&self) -> Result<lb_socketaddr> {
+        Ok(self.read_half()?.local_addr()?.into())
+    }
+
+    /// The remote socket address that this stream is connected to.
+    pub extern "Lua-C" fn peer_addr(&self) -> Result<lb_socketaddr> {
+        Ok(self.read_half()?.peer_addr()?.into())
+    }
+
+    /// Waits for this stream to be ready in the given half.
+    ///
+    /// The argument `half` can be `"read"` for the readable half, `"write"` for the writable half,
+    /// or `nil` for both.
+    pub async extern "Lua-C" fn ready(&self, half: Option<&str>) -> Result<()> {
+        self.read_half()?
+            .ready(match half {
+                Some("read") => Interest::READABLE,
+                Some("write") => Interest::WRITABLE,
+                None => Interest::READABLE | Interest::WRITABLE,
+                _ => Err(Error::InvalidSocketHalf)?,
+            })
+            .await?;
+
+        Ok(())
+    }
+
+    /// Closes this stream in the given half.
+    ///
+    /// The argument `half` can be `"read"` for the readable half, `"write"` for the writable half,
+    /// or `nil` for both.
+    ///
+    /// Once the half is closed, it can no longer be used for reading or writing for that half. Once
+    /// both halves are closed, the stream is fully shut down.
+    pub extern "Lua-C" fn close(&self, half: Option<&str>) -> Result<()> {
+        Ok(match half {
+            Some("read") => drop(self.read.try_borrow_mut()?.take()),
+            Some("write") => drop(self.write.try_borrow_mut()?.take()),
+            None => drop((
+                self.read.try_borrow_mut()?.take(),
+                self.write.try_borrow_mut()?.take(),
+            )),
+            _ => Err(Error::InvalidSocketHalf)?,
+        })
+    }
+
+    fn is_disc(err: ErrorKind) -> bool {
+        matches!(
+            err,
+            ErrorKind::ConnectionReset     // graceful shutdown
+                | ErrorKind::BrokenPipe    // abrupt shutdown
+                | ErrorKind::UnexpectedEof // could not read requested amount of data
+                | ErrorKind::WriteZero // could not write requested amount of data
+        )
+    }
+
+    /// Reads exactly `len` bytes from this stream.
+    ///
+    /// If the connection was closed, this returns `nil`.
+    pub async extern "Lua-C" fn read(&self, len: u32) -> Result<Option<Vec<u8>>> {
+        let mut buf = vec![0; len as usize];
+        Ok(match self.read_half()?.read_exact(&mut buf).await {
+            Ok(_) => Some(buf),
+            Err(err) if Self::is_disc(err.kind()) => None,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Reads up to `len` bytes from this stream.
+    ///
+    /// The returned bytes may be less than `len` in length if the stream had less data available in
+    /// queue. If there was no data available or the connection was closed, this returns `nil`.
+    pub async extern "Lua-C" fn read_partial(&self, len: u32) -> Result<Option<Vec<u8>>> {
+        let mut buf = vec![0; len as usize];
+        Ok(match self.read_half()?.read(&mut buf).await {
+            Ok(0) => None,
+            Ok(n) => Some({
+                buf.truncate(n);
+                buf
+            }),
+            Err(err) if Self::is_disc(err.kind()) => None,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Attempts to read up to `len` bytes from this stream without waiting.
+    ///
+    /// The returned bytes may be less than `len` in length if the stream had less data available in
+    /// queue. If there was no data available or the connection was closed, this returns `nil`.
+    pub extern "Lua-C" fn try_read(&self, len: u32) -> Result<Option<Vec<u8>>> {
+        let mut buf = vec![0; len as usize];
+        Ok(match self.read_half()?.try_read(&mut buf) {
+            Ok(0) => None,
+            Ok(n) => Some({
+                buf.truncate(n);
+                buf
+            }),
+            Err(err) if Self::is_disc(err.kind()) || err.kind() == ErrorKind::WouldBlock => None,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Writes exactly the given bytes to this stream.
+    ///
+    /// If the connection was closed, this returns `false`.
+    pub async extern "Lua-C" fn write(&self, buf: &[u8]) -> Result<bool> {
+        Ok(match self.write_half()?.write_all(buf).await {
+            Ok(()) => true,
+            Err(err) if Self::is_disc(err.kind()) => false,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Writes the given bytes to this stream, and returns the number of bytes successfully written.
+    ///
+    /// The returned number may be less than the length of `buf` if there was not enough space in
+    /// queue. If the connection was closed, this returns `nil`.
+    pub async extern "Lua-C" fn write_partial(&self, buf: &[u8]) -> Result<Option<u32>> {
+        Ok(match self.write_half()?.write(buf).await {
+            Ok(n) => Some(n as u32),
+            Err(err) if Self::is_disc(err.kind()) => None,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Attempts to write the given bytes to this stream without waiting, and returns the number of
+    /// bytes successfully written.
+    ///
+    /// The returned number may be less than the length of `buf` if there was not enough space in
+    /// queue. If the connection was closed, this returns `nil`.
+    pub extern "Lua-C" fn try_write(&self, buf: &[u8]) -> Result<Option<u32>> {
+        Ok(match self.write_half()?.try_write(buf) {
+            Ok(n) => Some(n as u32),
+            Err(err) if Self::is_disc(err.kind()) || err.kind() == ErrorKind::WouldBlock => None,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Peeks up to `len` bytes at incoming data without consuming it.
+    ///
+    /// Successive calls will return the same data until it is consumed by the [`read*`](Self::read)
+    /// family of functions.
+    pub async extern "Lua-C" fn peek(&self, len: u32) -> Result<Option<Vec<u8>>> {
+        let mut buf = vec![0; len as usize];
+        Ok(match self.read_half()?.peek(&mut buf).await {
+            Ok(0) => None,
+            Ok(n) => Some({
+                buf.truncate(n);
+                buf
+            }),
+            Err(err) if Self::is_disc(err.kind()) => None,
+            Err(err) => return Err(err.into()),
+        })
+    }
+
+    /// Alias for [`read_partial`](Self::read_partial).
+    #[call]
+    pub async extern "Lua" fn call(&self, len: u32) -> Result<Option<Vec<u8>>> {
+        self.read_partial(len)
+    }
+}
+
+/// TCP socket server, listening for connections.
+///
+/// This type represents a TCP server socket that can accept incoming connections. It is created by
+/// transitioning an [`lb_tcpsocket`] to the listening state via [`listen`](lb_tcpsocket::listen).
+///
+/// Methods on this type may fail if the operating system does not support the requested operation.
+///
+/// # Example
+///
+/// The listener can be used as an iterator in a generic `for` loop to accept incoming connections:
+///
+/// ```lua,no_run
+/// local net = require("lb:net")
+/// local listener = net.listen_tcp("127.0.0.1")
+///
+/// print("listening on: ", listener:local_addr())
+///
+/// for stream in listener do
+///     print("accepted connection from: ", stream:peer_addr())
+///     print("local address: ", stream:local_addr())
+///
+///     spawn(function()
+///         stream:write("hello from server\n")
+///         stream:close()
+///     end)
+/// end
+/// ```
+#[derive(Debug)]
+#[cdef]
+pub struct lb_tcplistener {
+    #[opaque]
+    listener: TcpListener,
+    __on_accept_ref: c_int,
+}
+
+#[metatype]
+impl lb_tcplistener {
+    pub(super) fn new(listener: TcpListener) -> Self {
+        Self {
+            listener,
+            __on_accept_ref: LUA_NOREF,
+        }
+    }
+
+    /// The local socket address that this listener is bound to.
+    pub extern "Lua-C" fn local_addr(&self) -> Result<lb_socketaddr> {
+        Ok(self.listener.local_addr()?.into())
+    }
+
+    /// Registers a callback to be invoked with each new incoming connection before it is converted
+    /// to an [`lb_tcpstream`].
+    ///
+    /// The callback receives a temporary [`lb_tcplistener_stream`] object, which can be used to log
+    /// incoming connections or configure socket options (such as
+    /// [`set_nodelay`](lb_tcplistener_stream), [`set_linger`](lb_tcplistener_stream), etc.) before
+    /// it is converted to an [`lb_tcpstream`]. The callback is called synchronously during
+    /// [`accept`](Self::accept) and should complete as quickly as possible. The provided
+    /// configurable object is only valid within the callback and is converted to an
+    /// [`lb_tcpstream`] as soon as it returns.
+    ///
+    /// If a callback already exists, it is replaced with the new one.
+    ///
+    /// # Example
+    ///
+    /// ```lua
+    /// local net = require("lb:net")
+    /// local listener = net.listen_tcp("127.0.0.1")
+    ///
+    /// listener:on_accept(function(stream)
+    ///     print("accepted connection from: ", stream:peer_addr())
+    ///     print("local address: ", stream:local_addr())
+    ///
+    ///     stream:set_nodelay(true)
+    /// end)
+    /// ```
+    pub extern "Lua" fn on_accept(&self, cb: fun<(&lb_tcplistener_stream,), ()>) {
+        assert(
+            rawequal(cb, ()) || r#type(cb) == "function",
+            concat!("function expected in argument 'cb', got ", r#type(cb)),
+        );
+        __unref(self.__on_accept_ref);
+        self.__on_accept_ref = __ref(cb);
+    }
+
+    /// Accepts a new incoming TCP connection.
+    ///
+    /// If an [`on_accept`](Self::on_accept) callback is registered, it is invoked with a temporary
+    /// [`lb_tcplistener_stream`] object representing the new connection. This allows configuration
+    /// of socket options for this specific connection, before the stream is converted to an
+    /// [`lb_tcpstream`] and returned for the connection to be read from or written to.
+    pub async extern "Lua" fn accept(&self) -> Result<lb_tcpstream> {
+        let stream = self.__accept();
+        let on_accept = __registry[self.__on_accept_ref];
+        if !rawequal(on_accept, ()) {
+            on_accept(stream);
+        }
+        stream.__convert()
+    }
+
+    async extern "Lua-C" fn __accept(&self) -> Result<lb_tcplistener_stream> {
+        let (stream, _) = self.listener.accept().await?;
+        Ok(lb_tcplistener_stream::new(stream))
+    }
+
+    /// Alias for [`accept`](Self::accept).
+    #[call]
+    pub async extern "Lua" fn call(&self) -> Result<lb_tcpstream> {
+        self.accept()
+    }
+
+    #[gc]
+    extern "Lua" fn gc(&self) {
+        __unref(self.__on_accept_ref);
+    }
+}
+
+/// TCP connection that has just been accepted by [`lb_tcplistener`].
+///
+/// This type is passed to the [`on_accept`](lb_tcplistener::on_accept) callback on
+/// [`lb_tcplistener`], allowing socket options to be set before the stream is converted to an
+/// [`lb_tcpstream`]. After conversion, this object can no longer be used.
+///
+/// Methods on this type may fail if the operating system does not support the requested operation.
+#[derive(Debug)]
+#[cdef]
+pub struct lb_tcplistener_stream(#[opaque] RefCell<Option<TcpStream>>);
+
+#[metatype]
+impl lb_tcplistener_stream {
+    fn new(stream: TcpStream) -> Self {
+        Self(RefCell::new(Some(stream)))
+    }
+
+    fn stream<'s>(&'s self) -> Result<Ref<'s, TcpStream>> {
+        let socket = self.0.borrow();
+        match *socket {
+            Some(_) => Ok(Ref::map(socket, |s| s.as_ref().unwrap())),
+            None => Err(Error::SocketConsumed),
+        }
+    }
+
+    /// The local socket address that the listener is bound to.
+    pub extern "Lua-C" fn local_addr(&self) -> Result<lb_socketaddr> {
+        Ok(self.stream()?.local_addr()?.into())
+    }
+
+    /// The remote socket address that this stream is connected to.
+    pub extern "Lua-C" fn peer_addr(&self) -> Result<lb_socketaddr> {
+        Ok(self.stream()?.peer_addr()?.into())
+    }
+
+    /// Gets the value of the `TCP_NODELAY` option on this stream.
+    pub extern "Lua-C" fn nodelay(&self) -> Result<bool> {
+        Ok(self.stream()?.nodelay()?)
+    }
+
+    /// Sets the value of the `TCP_NODELAY` option on this stream.
+    ///
+    /// This enables or disables Nagle's algorithm, which delays sending small packets.
+    pub extern "Lua-C" fn set_nodelay(&self, enabled: bool) -> Result<()> {
+        Ok(self.stream()?.set_nodelay(enabled)?)
+    }
+
+    /// Gets the value of the `SO_LINGER` option on this stream, in seconds.
+    pub extern "Lua-C" fn linger(&self) -> Result<f64> {
+        Ok(self
+            .stream()?
+            .linger()?
+            .map(|n| n.as_secs_f64())
+            .unwrap_or(0.))
+    }
+
+    /// Sets the value of the `SO_LINGER` option on this stream.
+    ///
+    /// This controls how long the stream will remain open after close if unsent data is present.
+    pub extern "Lua-C" fn set_linger(&self, secs: f64) -> Result<()> {
+        let secs = secs.max(0.);
+        Ok(self
+            .stream()?
+            .set_linger((secs != 0.).then_some(std::time::Duration::from_secs_f64(secs)))?)
+    }
+
+    /// Gets the value of the `IP_TTL` option for this stream.
+    pub extern "Lua-C" fn ttl(&self) -> Result<u32> {
+        Ok(self.stream()?.ttl()?)
+    }
+
+    /// Sets the value for the `IP_TTL` option on this stream.
+    pub extern "Lua-C" fn set_ttl(&self, ttl: u32) -> Result<()> {
+        Ok(self.stream()?.set_ttl(ttl)?)
+    }
+
+    extern "Lua-C" fn __convert(&self) -> Result<lb_tcpstream> {
+        Ok(lb_tcpstream::new(
+            self.0.borrow_mut().take().ok_or(Error::SocketConsumed)?,
+        ))
+    }
+}

crates/lb/src/runtime.lua

@@ -1,5 +0,0 @@
-local task = require("lb:task")
-
-function spawn(f, ...)
-  return task:spawn(f, ...)
-end

crates/lb/src/runtime.rs

@@ -1,85 +1,206 @@
-use crate::{channel::lb_libchannel, fs::lb_libfs, net::lb_libnet, task::lb_libtask};
+#![doc(hidden)]
 use derive_more::{Deref, DerefMut};
-use luaffi::{Registry, Type};
-use luajit::{Chunk, State};
-use std::fmt::Display;
+use luaffi::{Module, Registry};
+use luaify::luaify_chunk;
+use luajit::{Chunk, Index, NewTable, State};
+use std::rc::Rc;
 use tokio::{
     task::{JoinHandle, LocalSet, futures::TaskLocalFuture, spawn_local},
     task_local,
 };
 
-#[derive(Debug, Default)]
+pub type ErrorFn = dyn Fn(&luajit::Error);
+
 pub struct Builder {
     registry: Registry,
+    report_err: Rc<ErrorFn>,
+    jit_opts: Vec<String>,
+    prohibit_globals: bool,
 }
 
 impl Builder {
     pub fn new() -> Self {
-        let mut registry = Registry::new();
-
-        registry
-            .preload::<lb_libtask>("lb:task")
-            .preload::<lb_libchannel>("lb:channel")
-            .preload::<lb_libfs>("lb:fs")
-            .preload::<lb_libnet>("lb:net");
-
-        Self { registry }
-    }
-
-    pub fn module<T: Type>(&mut self, name: impl Display) -> &mut Self {
-        self.registry.preload::<T>(name);
-        self
+        Self {
+            registry: Registry::new(),
+            report_err: Rc::new(|err| match err.trace() {
+                Some(trace) => eprintln!("unhandled lua error: {err}\n{trace}"),
+                None => eprintln!("unhandled lua error: {err}"),
+            }),
+            jit_opts: vec![
+                // more aggressive jit options based on OpenResty's defaults
+                // https://github.com/openresty/luajit2#updated-jit-default-parameters
+                "maxtrace=8000".into(),
+                "maxrecord=16000".into(),
+                "minstitch=3".into(),
+                "maxmcode=40960".into(),
+            ],
+            prohibit_globals: false,
+        }
     }
 
     pub fn registry(&self) -> &Registry {
         &self.registry
     }
 
+    pub fn unhandled_error(&mut self, handler: impl Fn(&luajit::Error) + 'static) -> &mut Self {
+        self.report_err = Rc::new(handler);
+        self
+    }
+
+    pub fn prohibit_globals(&mut self, enabled: bool) -> &mut Self {
+        self.prohibit_globals = enabled;
+        self
+    }
+
+    pub fn jit_opt(&mut self, opt: impl AsRef<str>) -> &mut Self {
+        self.jit_opts.push(opt.as_ref().into());
+        self
+    }
+
+    pub fn jit_opts(&mut self, opts: impl IntoIterator<Item: AsRef<str>>) -> &mut Self {
+        for opt in opts {
+            self.jit_opt(opt);
+        }
+        self
+    }
+
+    pub fn module<T: Module>(&mut self) -> &mut Self {
+        self.registry.preload::<T>();
+        self
+    }
+
     pub fn build(&self) -> luajit::Result<Runtime> {
+        let mut state = State::new()?;
+        let chunk = Chunk::new(self.registry.build()).with_path("[luby]");
+        state.eval(&chunk, 0, Some(0))?;
+
+        if self.prohibit_globals {
+            state_prohibit_globals(&mut state)?;
+        }
+
+        for opt in self.jit_opts.iter() {
+            state_set_jitopt(&mut state, opt)?;
+        }
+
         Ok(Runtime {
-            state: {
-                let mut s = State::new()?;
-                let mut chunk = Chunk::new(self.registry.done());
-                chunk.extend(include_bytes!("./runtime.lua"));
-                s.eval(chunk.path("[luby]"), 0, 0)?;
-                s
+            cx: Context {
+                state,
+                report_err: self.report_err.clone(),
             },
             tasks: LocalSet::new(),
         })
     }
 }
 
-#[derive(Debug, Deref, DerefMut)]
+fn state_prohibit_globals(state: &mut State) -> luajit::Result<()> {
+    let mut s = state.guard();
+    let chunk = Chunk::new(luaify_chunk!({
+        return |self, key, value| {
+            error(("undeclared local variable '%s'").format(key), 2);
+        };
+    }))
+    .with_path("[luby]");
+    s.eval(&chunk, 0, Some(1)).unwrap();
+    s.push(NewTable::new());
+    (s.push("__index"), s.push_idx(-3), s.set(-3));
+    (s.push("__newindex"), s.push_idx(-3), s.set(-3));
+    s.set_metatable(Index::globals());
+    Ok(())
+}
+
+fn state_set_jitopt(state: &mut State, opt: &str) -> luajit::Result<()> {
+    let mut s = state.guard();
+    if let Some((cmd, opt)) = parse_jitlib_cmd(opt)
+        && let Ok(_) = s.require(format!("jit.{cmd}"), Some(1))
+    {
+        // require("jit.{cmd}").start(opt)
+        (s.push("start"), s.get(-2));
+        s.push(opt);
+        s.call(1, Some(0))?;
+    } else {
+        s.require("jit", Some(1)).unwrap();
+        match opt {
+            cmd @ ("on" | "off" | "flush") => {
+                // require("jit").<on|off|flush>()
+                (s.push(cmd), s.get(-2));
+                s.call(0, Some(0))?;
+            }
+            _ => {
+                // require("jit").opt.start(opt)
+                (s.push("opt"), s.get(-2));
+                (s.push("start"), s.get(-2));
+                s.push(opt);
+                s.call(1, Some(0))?;
+            }
+        }
+    }
+    Ok(())
+}
+
+fn parse_jitlib_cmd(cmd: &str) -> Option<(&str, &str)> {
+    match cmd {
+        "p" => Some(("p", "Flspv10")),    // default -jp flags
+        "v" => Some(("v", "-")),          // default -jv flags
+        "dump" => Some(("dump", "tirs")), // default -jdump flags
+        _ => cmd.split_once('='),
+    }
+}
+
+#[derive(Deref, DerefMut)]
 pub struct Runtime {
     #[deref]
     #[deref_mut]
-    state: State,
+    cx: Context,
     tasks: LocalSet,
 }
 
-task_local! {
-    static STATE: State;
-}
-
 impl Runtime {
     pub fn spawn<T: 'static>(
         &self,
-        f: impl AsyncFnOnce(&mut State) -> T + 'static,
+        f: impl AsyncFnOnce(&mut Context) -> T + 'static,
     ) -> JoinHandle<T> {
         self.tasks
-            .spawn_local(async move { f(&mut STATE.with(|s| s.new_thread())).await })
+            .spawn_local(async move { f(&mut CURRENT.with(|s| s.new_thread())).await })
     }
 }
 
-pub fn spawn<T: 'static>(f: impl AsyncFnOnce(&mut State) -> T + 'static) -> JoinHandle<T> {
-    spawn_local(async move { f(&mut STATE.with(|s| s.new_thread())).await })
-}
-
 impl IntoFuture for Runtime {
     type Output = ();
-    type IntoFuture = TaskLocalFuture<State, LocalSet>;
+    type IntoFuture = TaskLocalFuture<Context, LocalSet>;
 
     fn into_future(self) -> Self::IntoFuture {
-        STATE.scope(self.state, self.tasks)
+        CURRENT.scope(self.cx, self.tasks)
     }
 }
+
+task_local! {
+    static CURRENT: Context;
+}
+
+#[derive(Deref, DerefMut)]
+pub struct Context {
+    #[deref]
+    #[deref_mut]
+    state: State,
+    report_err: Rc<ErrorFn>,
+}
+
+impl Context {
+    pub fn new_thread(&self) -> Self {
+        Self {
+            state: State::new_thread(&self.state),
+            report_err: self.report_err.clone(),
+        }
+    }
+
+    pub fn report_error(&self, err: &luajit::Error) {
+        (self.report_err)(&err);
+    }
+}
+
+pub fn spawn<T: 'static>(f: impl AsyncFnOnce(&mut Context) -> T + 'static) -> JoinHandle<T> {
+    // SAFETY: `new_thread` must be called inside `spawn_local` because this free-standing spawn
+    // function may be called via ffi from lua, and it is not safe to access the lua state within
+    // ffi calls.
+    spawn_local(async move { f(&mut CURRENT.with(|s| s.new_thread())).await })
+}

crates/lb/src/task.lua

@@ -0,0 +1,3 @@
+local task = require("lb:task")
+sleep = task.sleep
+spawn = task.spawn

crates/lb/src/task.rs

@@ -1,46 +1,117 @@
+//! Task library.
+//!
+//! The `lb:task` library provides utilities for the scheduling of and communication between
+//! asynchronous tasks.
+//!
+//! ## Exports
+//!
+//! See [`lb_tasklib`] for items exported by this library.
 use crate::runtime::spawn;
-use luaffi::{cdef, metatype};
-use std::{ffi::c_int, process};
-use tokio::task::JoinHandle;
+use luaffi::{
+    cdef,
+    marker::{function, many},
+    metatype,
+};
+use std::{cell::RefCell, ffi::c_int, time::Duration};
+use tokio::{task::JoinHandle, time::sleep};
 
-#[cdef]
-pub struct lb_libtask;
+/// Items exported by the `lb:task` library.
+///
+/// This library can be acquired by calling
+/// [`require("lb:task")`](https://www.lua.org/manual/5.1/manual.html#pdf-require).
+///
+/// ```lua
+/// local task = require("lb:task")
+/// ```
+#[cdef(module = "lb:task")]
+pub struct lb_tasklib;
 
 #[metatype]
-impl lb_libtask {
+#[include("task.lua")]
+impl lb_tasklib {
     #[new]
     extern "Lua-C" fn new() -> Self {
         Self
     }
 
-    pub extern "Lua" fn spawn(self, f: function, ...) {
-        // pack the function and its arguments into a table and pass its ref to rust
-        self.__spawn(__ref(__tpack(f, variadic!())))
+    pub async extern "Lua-C" fn sleep(ms: f64) {
+        sleep(Duration::from_secs_f64(ms.max(0.) / 1000.)).await;
     }
 
-    extern "Lua-C" fn __spawn(&self, key: c_int) -> lb_task {
-        let handle = spawn(async move |s| {
-            // SAFETY: key is always unique, created by __ref above
-            let arg = unsafe { s.new_ref_unchecked(key) };
+    pub extern "Lua" fn spawn(f: function, ...) -> lb_task {
+        // pack the function and its arguments into a table and pass its ref to rust.
+        //
+        // this "state" table is used from rust-side to call the function with its args, and it's
+        // also reused to store its return values that the task handle can return when awaited. the
+        // ref is owned by the task handle and unref'ed when it's gc'ed.
+        assert(
+            r#type(f) == "function",
+            concat!("function expected in argument 'f', got ", r#type(f)),
+        );
+        // we need two refs: one for the spawn call, and the other for the task handle. this is to
+        // ensure the task handle isn't gc'ed and the state table unref'ed before the spawn callback
+        // runs and puts the state table on the stack.
+        let state = __tpack(f, variadic!());
+        Self::__spawn(__ref(state), __ref(state))
+    }
+
+    extern "Lua-C" fn __spawn(spawn_ref: c_int, handle_ref: c_int) -> lb_task {
+        let handle = spawn(async move |cx| {
+            // SAFETY: handle_ref is always unique, created in Self::spawn above.
+            let state = unsafe { luajit::Ref::from_raw(cx, spawn_ref) };
+            let mut s = cx.guard();
             s.resize(0);
-            s.push(arg);
-            let narg = s.unpack(1, 1, None) - 1;
-            println!("{s:?}");
-            if let Err(_err) = s.call_async(narg, 0).await {
-                process::exit(1)
+            s.push(state); // this drops the state table ref, but the table is still on the stack
+            let narg = s.unpack(1, 1, None) - 1; // unpack the function and its args from the state table
+            match s.call_async(narg, None).await {
+                Ok(nret) => {
+                    s.pack(1, nret); // pack the return values back into the state table
+                }
+                Err(err) => {
+                    drop(s);
+                    cx.report_error(&err);
+                }
             }
-            println!("{s:?}");
         });
 
-        lb_task { handle }
+        // spawn_ref is owned by the task handle and unref'ed there when the handle gets gc'ed
+        lb_task::new(handle, handle_ref)
     }
 }
 
+/// Handle for an asynchronous task created by [`spawn`](lb_tasklib::spawn).
 #[cdef]
 pub struct lb_task {
     #[opaque]
-    handle: JoinHandle<()>,
+    handle: RefCell<Option<JoinHandle<()>>>,
+    __ref: c_int,
 }
 
 #[metatype]
-impl lb_task {}
+impl lb_task {
+    fn new(handle: JoinHandle<()>, ref_key: c_int) -> Self {
+        lb_task {
+            handle: RefCell::new(Some(handle)),
+            __ref: ref_key,
+        }
+    }
+
+    pub async extern "Lua" fn r#await(&self) -> many {
+        self.__await();
+        let ret = __registry[self.__ref];
+        __tunpack(ret, 1, ret.n)
+    }
+
+    async extern "Lua-C" fn __await(&self) {
+        if let Some(handle) = self.handle.borrow_mut().take() {
+            handle
+                .await // task handler should never panic
+                .unwrap_or_else(|err| std::panic::resume_unwind(err.into_panic()));
+        }
+    }
+
+    #[gc]
+    extern "Lua" fn gc(&self) {
+        __unref(self.__ref);
+    }
+}

crates/lb/src/time.rs

@@ -0,0 +1,49 @@
+//! Time library.
+//!
+//! The `lb:time` library provides utilities for working with the date and time and its related
+//! constructs.
+//!
+//! ## Exports
+//!
+//! See [`lb_timelib`] for items exported by this library.
+use luaffi::{cdef, metatype};
+
+/// Items exported by the `lb:time` library.
+///
+/// This library can be acquired by calling
+/// [`require("lb:time")`](https://www.lua.org/manual/5.1/manual.html#pdf-require).
+///
+/// ```lua
+/// local time = require("lb:time")
+/// ```
+#[cdef(module = "lb:time")]
+pub struct lb_timelib;
+
+#[metatype]
+impl lb_timelib {
+    #[new]
+    extern "Lua-C" fn new() -> Self {
+        Self
+    }
+
+    /// Returns an instant object that represents the current time at the time of calling.
+    pub extern "Lua-C" fn instant() -> lb_instant {
+        lb_instant::new(std::time::Instant::now())
+    }
+}
+
+/// Represents the measurement of a monotonically nondecreasing clock.
+#[cdef]
+pub struct lb_instant(#[opaque] std::time::Instant);
+
+#[metatype]
+impl lb_instant {
+    fn new(instant: std::time::Instant) -> Self {
+        Self(instant)
+    }
+
+    /// Returns the number of seconds elapsed since this instant was measured.
+    pub extern "Lua-C" fn elapsed_secs(&self) -> f64 {
+        self.0.elapsed().as_secs_f64()
+    }
+}

crates/lb/tests/fs.lua

@@ -0,0 +1,17 @@
+local ok, fs = pcall(require, "lb:fs")
+if not ok then return end
+
+describe("temp files", function()
+  test("temp_dir cleans itself", function()
+    local path
+    do
+      local dir = fs.temp_dir()
+      path = dir:path()
+      assert(path and path ~= "")
+      fs.write(path .. "/test.txt", "test file")
+      assert(fs.read(path .. "/test.txt") == "test file")
+    end
+    collectgarbage()
+    assert(not pcall(fs.read, path .. "/test.txt"))
+  end)
+end)

crates/lb/tests/net.lua

@@ -0,0 +1,184 @@
+local ok, net = pcall(require, "lb:net")
+if not ok then return end
+
+describe("ipaddr", function()
+  test("invalid ipaddr throws", function()
+    assert(not pcall(net.ipaddr, "invalid ip"))
+  end)
+
+  test("comparison", function()
+    local a = net.ipaddr("10.0.0.1")
+    local b = net.ipaddr("10.0.0.1")
+    local c = net.ipaddr("10.0.0.2")
+    assert(a ~= nil and a ~= {} and a ~= "10.0.0.1" and a ~= 167772161)
+    assert(a == a and a == b and a ~= c and b ~= c and c == c and c ~= a)
+    assert(a <= b and a < c and a <= c and b < c and b <= c and a <= a and c <= c)
+    assert(not (a < b or a > b or a > c or b > c or a >= c or b >= c))
+  end)
+
+  test("tostring", function()
+    local ip = net.ipaddr("10.0.0.1")
+    assert(tostring(ip) == "10.0.0.1")
+  end)
+end)
+
+describe("tcp", function()
+  describe("socket", function()
+    test("bind", function()
+      local socket = net.bind_tcp("127.0.0.1")
+      -- binds to the correct port
+      assert(tostring(socket:local_addr():ip()) == "127.0.0.1")
+      assert(socket:local_addr():port() ~= 0)
+      -- should not be able to rebind socket
+      assert(not pcall(socket.bind, socket, net.socketaddr("127.0.0.1")))
+    end)
+
+    test("options", function()
+      local socket = net.tcp()
+      -- keepalive
+      socket:set_keepalive(true)
+      assert(socket:keepalive() == true)
+      socket:set_keepalive(false)
+      assert(socket:keepalive() == false)
+      -- reuseaddr
+      socket:set_reuseaddr(true)
+      assert(socket:reuseaddr() == true)
+      socket:set_reuseaddr(false)
+      assert(socket:reuseaddr() == false)
+      -- reuseport not always supported on all platforms
+      -- sendbuf
+      socket:set_sendbuf(4096)
+      assert(socket:sendbuf() >= 4096)
+      assert(not pcall(socket.set_sendbuf, socket, 0))
+      assert(not pcall(socket.set_sendbuf, socket, -1))
+      -- recvbuf
+      socket:set_recvbuf(4096)
+      assert(socket:recvbuf() >= 4096)
+      assert(not pcall(socket.set_recvbuf, socket, 0))
+      assert(not pcall(socket.set_recvbuf, socket, -1))
+      -- linger
+      socket:set_linger(0)
+      assert(socket:linger() == 0)
+      socket:set_linger(2)
+      assert(math.abs(socket:linger() - 2) < 0.1)
+      socket:set_linger(-1)
+      assert(socket:linger() == 0)
+      -- nodelay
+      socket:set_nodelay(true)
+      assert(socket:nodelay() == true)
+      socket:set_nodelay(false)
+      assert(socket:nodelay() == false)
+    end)
+
+    test("can't use socket after conversion", function()
+      local socket = net.tcp()
+      socket:bind(net.socketaddr("127.0.0.1"))
+      socket:listen(10) -- convert to listener
+      assert(not pcall(socket.listen, socket, 10)) -- socket consumed
+      assert(not pcall(socket.local_addr, socket))
+    end)
+  end)
+
+  describe("stream", function()
+    test("no concurrent two reads/writes", function()
+      local listener = net.listen_tcp(net.localhost())
+      local client = net.connect_tcp(listener:local_addr())
+      local server = listener()
+      local reader = spawn(function()
+        assert(client:read(1) == nil) -- this should block first, then return nil from disconnection
+      end)
+      spawn(function()
+        assert(not pcall(client.read, client, 1)) -- this should fail, since the first task is still reading
+      end):await()
+      server:close()
+      reader:await()
+    end)
+
+    test("allow concurrent read/write", function()
+      local listener = net.listen_tcp(net.localhost())
+      local client = net.connect_tcp(listener:local_addr())
+      local server = listener()
+      local reader = spawn(function()
+        assert(client:read(1) == nil) -- this should block first, then return nil from disconnection
+      end)
+      spawn(function()
+        client:write("hello") -- should be able to write while the first task is reading
+      end):await()
+      server:close()
+      reader:await()
+    end)
+
+    test("stop reading from disconnected stream", function()
+      local listener = net.listen_tcp(net.localhost())
+      local client = net.connect_tcp(listener:local_addr())
+      local server = listener()
+      local reader = spawn(function()
+        while client:read(4) ~= nil do
+        end
+        assert(client:try_read(4) == nil)
+        assert(client:read_partial(4) == nil)
+        assert(client:read(4) == nil)
+      end)
+      for _ = 1, 10 do
+        assert(server:write("ping") == true)
+      end
+      sleep(100)
+      server:close()
+      reader:await()
+    end)
+
+    test("stop writing to disconnected stream", function()
+      local listener = net.listen_tcp(net.localhost())
+      local client = net.connect_tcp(listener:local_addr())
+      local server = listener()
+      local writer = spawn(function()
+        while client:write("pong") do
+        end
+        assert(client:try_write("pong") == nil)
+        assert(client:write_partial("pong") == nil)
+        assert(client:write("pong") == false)
+      end)
+      for _ = 1, 10 do
+        assert(server:read(4) == "pong")
+      end
+      sleep(100)
+      server:close()
+      writer:await()
+    end)
+  end)
+
+  describe("listener", function()
+    test("accept", function()
+      local listener = net.listen_tcp(net.localhost())
+      local addr = listener:local_addr()
+      local accepted = false
+      local client = net.tcp()
+      local accepted_stream
+      listener:on_accept(function(stream)
+        accepted = true
+        accepted_stream = stream
+        -- configure stream
+        stream:set_nodelay(true)
+        assert(stream:nodelay() == true)
+      end)
+      -- connect client
+      local client_stream = client:connect(addr)
+      local server_stream = listener()
+      assert(accepted)
+      assert(accepted_stream ~= nil)
+      -- check addresses
+      assert(server_stream:local_addr() ~= nil)
+      assert(server_stream:peer_addr() ~= nil)
+      assert(client_stream:local_addr() ~= nil)
+      assert(client_stream:peer_addr() ~= nil)
+      -- test data transfer
+      server_stream:write("hello")
+      local buf = client_stream:read(5)
+      assert(buf ~= nil and #buf == 5)
+      assert(buf == "hello")
+      -- close
+      server_stream:close()
+      client_stream:close()
+    end)
+  end)
+end)

crates/lb/tests/net.rs

@@ -1,32 +0,0 @@
-use lb::runtime;
-use luaify::luaify;
-use luajit::{Chunk, LoadMode};
-use tokio::test;
-
-async fn run_lua(s: &'static str) {
-    let rt = runtime::Builder::new().build().unwrap();
-    let task = rt.spawn(async move |state| {
-        println!("executing test chunk: {s}");
-
-        state
-            .load(Chunk::new(s).mode(LoadMode::TEXT))
-            .unwrap_or_else(|err| panic!("{err}"));
-
-        state
-            .call_async(0, 0)
-            .await
-            .unwrap_or_else(|err| panic!("{err}"));
-    });
-
-    rt.await;
-    task.await.unwrap_or_else(|err| panic!("{err}"));
-}
-
-#[test]
-async fn ipaddr() {
-    run_lua(luaify!({
-        let net = require("lb:net");
-        print(net.ipaddr("127.0.0.1"));
-    }))
-    .await
-}

crates/lb/tests/task.lua

@@ -0,0 +1,189 @@
+local ok, task = pcall(require, "lb:task")
+if not ok then return end
+
+describe("spawn", function()
+  test("callback receives args", function()
+    spawn(function(...)
+      assert(select("#", ...) == 0)
+    end):await()
+
+    spawn(function(...)
+      assert(select("#", ...) == 1)
+      assert((...) == nil)
+    end, nil):await()
+
+    spawn(function(...)
+      assert(select("#", ...) == 4)
+      local args = table.pack(...)
+      assert(args[1] == 1 and args[2] == 2 and args[3] == nil and args[4] == 3)
+    end, 1, 2, nil, 3):await()
+  end)
+
+  test("await returns callback results", function()
+    local res = table.pack(spawn(function()
+      -- no returns
+    end):await())
+    assert(res.n == 0)
+
+    local res = table.pack(spawn(function()
+      return nil
+    end):await())
+    assert(res.n == 1 and res[1] == nil)
+
+    local res = table.pack(spawn(function()
+      return 1, 2, nil, 3
+    end):await())
+    assert(res.n == 4 and res[1] == 1 and res[2] == 2 and res[3] == nil and res[4] == 3)
+  end)
+
+  test("handles invalid args", function()
+    assert(not pcall(spawn))
+    assert(not pcall(spawn, 123))
+    assert(not pcall(spawn, 1, 2, 3))
+    assert(not pcall(spawn, {}, 2, 3))
+  end)
+
+  test("callback args and results", function()
+    local res = table.pack(spawn(function(...)
+      assert(select("#", ...) == 5)
+      local args = table.pack(...)
+      assert(args[1] == 5 and args[2] == 4 and args[3] == nil and args[4] == 3, args[5] == nil)
+      return 1, 3, nil
+    end, 5, 4, nil, 3, nil):await())
+    assert(res.n == 3 and res[1] == 1 and res[2] == 3 and res[3] == nil)
+  end)
+
+  test("large number of args", function()
+    local args = {}
+    for i = 1, 1000 do
+      args[i] = i
+    end
+    local res = table.pack(spawn(function(...)
+      return ...
+    end, table.unpack(args)):await())
+    assert(res.n == 1000 and res[1] == 1 and res[1000] == 1000)
+  end)
+
+  test("callback closes over upvalues", function()
+    local x = 42
+    local function f()
+      return x
+    end
+    assert(spawn(f):await() == 42)
+  end)
+
+  test("order is consistent", function()
+    -- all tasks spawned in one batch should be resumed in the spawn order
+    local tasks, nums = {}, {}
+    for i = 1, 10 do
+      table.insert(
+        tasks,
+        spawn(function()
+          table.insert(nums, i)
+        end)
+      )
+    end
+    for i = 10, 1, -1 do
+      tasks[i]:await()
+    end
+    assert(#nums == 10)
+    for i = 1, 10 do
+      assert(nums[i] == i)
+    end
+  end)
+
+  test("nested spawns", function()
+    local result = {}
+    local function inner()
+      table.insert(result, "inner")
+      return "done"
+    end
+    local function outer()
+      table.insert(result, "outer")
+      local v = spawn(inner):await()
+      table.insert(result, v)
+      return v
+    end
+    local v = spawn(outer):await()
+    assert(v == "done")
+    assert(result[1] == "outer" and result[2] == "inner" and result[3] == "done")
+  end)
+end)
+
+describe("sleep", function()
+  test("invalid arg", function()
+    assert(not pcall(task.sleep, "invalid"))
+    task.sleep(-1) -- negative sleep should just become 0ms
+  end)
+
+  test("sleep is asynchronous", function()
+    local value
+    spawn(function()
+      value = "value"
+    end)
+    assert(value == nil)
+    task.sleep(100) -- implicit await: if it's synchronous, value wouldn't change
+    assert(value == "value")
+  end)
+
+  test("sleep in nested spawns", function()
+    local value1, value2, value3 = nil, nil, nil
+    local results = {}
+    local function inner()
+      task.sleep(30)
+      value1 = "set by inner"
+      table.insert(results, "inner")
+      return value1
+    end
+    local function middle()
+      task.sleep(20)
+      value2 = "set by middle"
+      local v = spawn(inner):await()
+      table.insert(results, v)
+      table.insert(results, "middle")
+      return v, value2
+    end
+    local function outer()
+      task.sleep(10)
+      value3 = "set by outer"
+      local v1, v2 = spawn(middle):await()
+      table.insert(results, v1)
+      table.insert(results, v2)
+      table.insert(results, "outer")
+      return v1, v2, value3
+    end
+    assert(value1 == nil and value2 == nil and value3 == nil)
+    local r1, r2, r3 = spawn(outer):await()
+    assert(r1 == "set by inner" and r2 == "set by middle" and r3 == "set by outer")
+    assert(value1 == "set by inner" and value2 == "set by middle" and value3 == "set by outer")
+    assert(results[1] == "inner")
+    assert(results[2] == "set by inner")
+    assert(results[3] == "middle")
+    assert(results[4] == "set by inner")
+    assert(results[5] == "set by middle")
+    assert(results[6] == "outer")
+  end)
+end)
+
+describe("task", function()
+  test("properly unrefs arg and ret table", function()
+    local registry = debug.getregistry()
+    local ref, t
+    local cb = function()
+      return "my ret"
+    end
+    do
+      local task = spawn(cb, "my arg")
+      ref = task.__ref
+      t = registry[ref]
+      assert(type(t) == "table")
+      assert(t[1] == cb)
+      assert(t[2] == "my arg")
+      task:await()
+      assert(registry[task.__ref] == t)
+      assert(t[1] == "my ret")
+    end
+    collectgarbage()
+    assert(registry[ref] ~= t) -- if task unref'ed it, it should be either nil or the next freelist number
+  end)
+end)

crates/lb/tests/task.rs

@@ -1,35 +0,0 @@
-use lb::runtime;
-use luaify::luaify;
-use luajit::{Chunk, LoadMode};
-use tokio::test;
-
-async fn run_lua(s: &'static str) {
-    let rt = runtime::Builder::new().build().unwrap();
-    let task = rt.spawn(async move |state| {
-        println!("executing test chunk: {s}");
-
-        state
-            .load(Chunk::new(s).mode(LoadMode::TEXT))
-            .unwrap_or_else(|err| panic!("{err}"));
-
-        state
-            .call_async(0, 0)
-            .await
-            .unwrap_or_else(|err| panic!("{err}"));
-    });
-
-    rt.await;
-    task.await.unwrap_or_else(|err| panic!("{err}"));
-}
-
-#[test]
-async fn task_test() {
-    run_lua(luaify!({
-        let thing = spawn(|| {
-            print("spawn callback!!!!!!!!!!!!!");
-        });
-        print("thing is", thing);
-        //
-    }))
-    .await
-}

crates/lb_sqlite/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "lb_sqlite"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
+
+[dependencies]
+lb = { path = "../lb", features = ["time"] }
+luaffi = { version = "0.0.1", path = "../luaffi" }
+rusqlite = { version = "0.36.0", features = ["bundled", "load_extension", "backup", "blob", "limits", "window", "series", "session", "collation", "serialize"] }

crates/lb_sqlite/src/lib.rs

@@ -0,0 +1,3 @@
+//! luby SQLite library.
+#[path = "mod.rs"]
+pub mod sqlite;

crates/lb_sqlite/src/mod.rs

@@ -0,0 +1,27 @@
+//! SQLite library.
+//!
+//! The `lb:sqlite` library provides an interface to SQLite databases.
+//!
+//! ## Exports
+//!
+//! See [`lb_sqlitelib`] for items exported by this library.
+use luaffi::{cdef, metatype};
+
+/// Items exported by the `lb:sqlite` library.
+///
+/// This library can be acquired by calling
+/// [`require("lb:sqlite")`](https://www.lua.org/manual/5.1/manual.html#pdf-require).
+///
+/// ```lua
+/// local sqlite = require("lb:sqlite")
+/// ```
+#[cdef(module = "lb:sqlite")]
+pub struct lb_sqlitelib;
+
+#[metatype]
+impl lb_sqlitelib {
+    #[new]
+    extern "Lua-C" fn new() -> Self {
+        Self
+    }
+}

crates/luaffi/Cargo.toml

@@ -1,11 +1,19 @@
 [package]
 name = "luaffi"
-version = "0.1.0"
-edition = "2024"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
+
+[features]
+option_ref_abi = []
+option_string_abi = []
 
 [dependencies]
 bstr = "1.12.0"
-luaffi_impl = { version = "0.1.0", path = "../luaffi_impl" }
-luaify = { version = "0.1.0", path = "../luaify" }
+luaffi_impl = { path = "../luaffi_impl" }
+luaify = { path = "../luaify" }
 rustc-hash = "2.1.1"
 simdutf8 = "0.1.5"

crates/luaffi/src/future.rs

@@ -1,7 +1,7 @@
 use crate::{
     __internal::{display, type_id},
-    Cdef, CdefBuilder, FfiReturnConvention, IntoFfi, Metatype, MetatypeBuilder, Type, TypeBuilder,
-    TypeType, UnsafeExternCFn,
+    Cdef, CdefBuilder, ExternCFn, FfiReturnConvention, IntoFfi, Metatype, MetatypeBuilder, Type,
+    TypeBuilder, TypeType,
 };
 use luaify::luaify;
 use std::{
@@ -70,6 +70,45 @@ enum State<F: Future> {
     Complete,
 }
 
+unsafe impl<F: Future<Output: IntoFfi> + 'static> Type for lua_future<F> {
+    fn name() -> impl Display {
+        display!("__future_{:x}", type_id::<F>())
+    }
+
+    fn ty() -> TypeType {
+        TypeType::Aggregate
+    }
+
+    fn cdecl(name: impl Display) -> impl Display {
+        display!("struct {} {name}", Self::name())
+    }
+
+    fn build(s: &mut TypeBuilder) {
+        s.cdef::<Self>().metatype::<Self>();
+    }
+}
+
+unsafe impl<F: Future<Output: IntoFfi> + 'static> Cdef for lua_future<F> {
+    fn build(s: &mut CdefBuilder) {
+        s.field_opaque(mem::offset_of!(Self, take)) // opaque .sig, .poll and .state
+            .field::<ExternCFn<(&mut Self,), <F::Output as IntoFfi>::Into>>("__take")
+            .field::<ExternCFn<(&mut Self,), ()>>("__drop");
+    }
+}
+
+unsafe impl<F: Future<Output: IntoFfi> + 'static> Metatype for lua_future<F> {
+    type Target = Self;
+
+    fn build(s: &mut MetatypeBuilder) {
+        s.metatable_raw(
+            "gc",
+            luaify!(|self| {
+                self.__drop();
+            }),
+        );
+    }
+}
+
 impl<F: Future<Output: IntoFfi>> lua_future<F> {
     pub fn new(fut: F) -> Self {
         Self {
@@ -117,7 +156,12 @@ impl lua_pollable {
     pub fn is_valid(&self) -> bool {
         // TODO: signature check can currently read out-of-bounds if lua code for some reason yields
         // a cdata of size less than 8 bytes that is not a lua_future. there is no easy way to fix
-        // afaik this because there is no way to find the size of a cdata payload using the C API.
+        // AFAIK this because there is no way to find the size of a cdata payload using the C API.
+        // unfortunately we have to trust that the user won't do that right now.
+        //
+        // the only "saving grace" is that the user should never be running untrusted code anyway,
+        // because this whole project is based on the ffi library which should never be exposed to
+        // untrusted code in the first place.
         self.sig == SIGNATURE
     }
 }
@@ -131,40 +175,6 @@ impl Future for lua_pollable {
     }
 }
 
-unsafe impl<F: Future<Output: IntoFfi> + 'static> Type for lua_future<F> {
-    fn name() -> impl Display {
-        display!("future__{:x}", type_id::<F>())
-    }
-
-    fn ty() -> TypeType {
-        TypeType::Aggregate
-    }
-
-    fn cdecl(name: impl Display) -> impl Display {
-        display!("struct {} {name}", Self::name())
-    }
-
-    fn build(s: &mut TypeBuilder) {
-        s.cdef::<Self>().metatype::<Self>();
-    }
-}
-
-unsafe impl<F: Future<Output: IntoFfi> + 'static> Cdef for lua_future<F> {
-    fn build(s: &mut CdefBuilder) {
-        s.field_opaque(mem::offset_of!(Self, take)) // opaque .sig, .poll and .state
-            .field::<UnsafeExternCFn<(&mut Self,), <F::Output as IntoFfi>::Into>>("__take")
-            .field::<UnsafeExternCFn<(&mut Self,), ()>>("__drop");
-    }
-}
-
-unsafe impl<F: Future<Output: IntoFfi> + 'static> Metatype for lua_future<F> {
-    type Target = Self;
-
-    fn build(s: &mut MetatypeBuilder) {
-        s.metatable_raw("gc", luaify!(|self| self.__drop()));
-    }
-}
-
 unsafe impl<F: Future<Output: IntoFfi> + 'static> IntoFfi for lua_future<F> {
     type Into = lua_future<F>;
 
@@ -177,6 +187,15 @@ unsafe impl<F: Future<Output: IntoFfi> + 'static> IntoFfi for lua_future<F> {
         self
     }
 
+    fn require_owned() -> bool {
+        // future always requires full ownership of itself even if it's a "temporary", because we
+        // must yield a full cdata to the runtime not a cdata containing a pointer to the future. if
+        // this is set to false, postlude might receive a reference lua_future cdata instead of a
+        // full lua_future cdata, and the runtime might incorrectly read the pointer value as
+        // lua_future itself (it does not dereference it).
+        true
+    }
+
     fn postlude(ret: &str) -> impl Display {
         // When returning a future from Rust to Lua, yield it immediately to the runtime which will
         // poll it to completion in the background, then take the fulfilled value once the thread

crates/luaffi/src/internal.rs

@@ -6,23 +6,6 @@ use std::{
     hash::{Hash, Hasher},
 };
 
-#[allow(non_camel_case_types)]
-pub mod stub_types {
-    pub struct any;
-    pub struct nil;
-    pub struct boolean;
-    pub struct lightuserdata;
-    pub struct number;
-    pub struct integer;
-    pub struct string;
-    pub struct table;
-    pub struct function;
-    pub struct userdata;
-    pub struct thread;
-    pub struct cdata;
-    pub struct variadic;
-}
-
 pub fn type_id<T: 'static>() -> u64 {
     let mut hash = FxHasher::default();
     TypeId::of::<T>().hash(&mut hash);

crates/luaffi/src/lib.lua

@@ -1,24 +1,22 @@
+---@diagnostic disable
 local LUA_REFNIL = -1 -- lib_aux.c
 local FREELIST_REF = 0
 
-local function __ref(value, t)
-  if value == nil then return LUA_REFNIL end
-  if t == nil then t = __registry end
-  local ref = t[FREELIST_REF]
+local function __ref(value)
+  if rawequal(value, nil) then return LUA_REFNIL end
+  local ref = __registry[FREELIST_REF]
   if ref ~= nil and ref ~= 0 then
-    t[FREELIST_REF] = t[ref]
+    __registry[FREELIST_REF] = __registry[ref]
   else
-    ref = #t + 1
+    ref = rawlen(__registry) + 1
   end
-  t[ref] = value
+  __registry[ref] = value
   return ref
 end
 
-local function __unref(ref, t)
-  if ref < 0 then return nil end
-  if t == nil then t = __registry end
-  local value = t[ref]
-  t[ref] = t[FREELIST_REF]
-  t[FREELIST_REF] = ref
-  return value
+local function __unref(ref)
+  if ref > 0 then
+    __registry[ref] = __registry[FREELIST_REF]
+    __registry[FREELIST_REF] = ref
+  end
 end

crates/luaffi/src/marker.rs

@@ -0,0 +1,193 @@
+#![allow(non_camel_case_types)]
+use crate::{
+    __internal::{disp, display},
+    Annotate,
+};
+use std::{fmt::Display, marker::PhantomData};
+
+enum Marker {}
+
+pub struct any(Marker);
+
+impl Annotate for any {
+    fn annotation() -> impl Display {
+        "any"
+    }
+}
+
+pub struct many(Marker);
+
+impl Annotate for many {
+    fn annotation() -> impl Display {
+        "..."
+    }
+}
+
+pub struct nil(Marker);
+
+impl Annotate for nil {
+    fn annotation() -> impl Display {
+        "nil"
+    }
+}
+
+pub struct lightuserdata(Marker);
+
+impl Annotate for lightuserdata {
+    fn annotation() -> impl Display {
+        "lightuserdata"
+    }
+}
+
+pub struct table<K, V>(Marker, PhantomData<*mut [(K, V)]>);
+
+impl<K, V> Annotate for table<K, V>
+where
+    K: Annotate,
+    V: Annotate,
+{
+    fn annotation() -> impl Display {
+        display!("table<{}, {}>", K::annotation(), V::annotation())
+    }
+}
+
+pub struct function(Marker);
+
+impl Annotate for function {
+    fn annotation() -> impl Display {
+        "function"
+    }
+}
+
+pub struct fun<I, O>(Marker, PhantomData<fn(I) -> O>);
+
+macro_rules! impl_fun {
+    (fn($($arg:ident),*)) => {
+        impl<$($arg,)*> Annotate for fun<($($arg,)*), ()>
+        where
+            $($arg: Annotate,)*
+        {
+            fn annotation() -> impl Display {
+                disp(|f| {
+                    write!(f, "fun(")?;
+                    let mut _n = 0;
+                    $(if _n != 0 { write!(f, ", ")?; } write!(f, "{}", $arg::annotation())?; _n += 1;)*
+                    write!(f, ")")
+                })
+            }
+        }
+    };
+
+    (fn($($arg:ident),*) -> $ret:ident) => {
+        impl<$($arg,)* $ret> Annotate for fun<($($arg,)*), $ret>
+        where
+            $($arg: Annotate,)*
+            $ret: Annotate,
+        {
+            fn annotation() -> impl Display {
+                disp(|f| {
+                    write!(f, "fun(")?;
+                    let mut _n = 0;
+                    $(if _n != 0 { write!(f, ", ")?; } write!(f, "{}", $arg::annotation())?; _n += 1;)*
+                    write!(f, "): {}", $ret::annotation())
+                })
+            }
+        }
+
+        impl_fun!(fn($($arg),*));
+    };
+}
+
+impl_fun!(fn() -> A);
+impl_fun!(fn(A) -> B);
+impl_fun!(fn(A, B) -> C);
+impl_fun!(fn(A, B, C) -> D);
+impl_fun!(fn(A, B, C, D) -> E);
+impl_fun!(fn(A, B, C, D, E) -> F);
+impl_fun!(fn(A, B, C, D, E, F) -> G);
+impl_fun!(fn(A, B, C, D, E, F, G) -> H);
+impl_fun!(fn(A, B, C, D, E, F, G, H) -> I);
+impl_fun!(fn(A, B, C, D, E, F, G, H, I) -> J);
+
+pub struct userdata(Marker);
+
+impl Annotate for userdata {
+    fn annotation() -> impl Display {
+        "userdata"
+    }
+}
+
+pub struct thread(Marker);
+
+impl Annotate for thread {
+    fn annotation() -> impl Display {
+        "thread"
+    }
+}
+
+pub struct cdata(Marker);
+
+impl Annotate for cdata {
+    fn annotation() -> impl Display {
+        "cdata"
+    }
+}
+
+pub struct Either<T, U>(Marker, PhantomData<(T, U)>);
+
+impl<T, U> Annotate for Either<T, U>
+where
+    T: Annotate,
+    U: Annotate,
+{
+    fn annotation() -> impl Display {
+        display!("({} | {})", T::annotation(), U::annotation())
+    }
+}
+
+pub struct OneOf<X>(Marker, PhantomData<X>);
+
+macro_rules! impl_oneof {
+    ($($ty:ident),+) => {
+        impl<$($ty),+> Annotate for OneOf<($($ty,)+)>
+        where
+            $($ty: Annotate),+
+        {
+            fn annotation() -> impl Display {
+                disp(|f| {
+                    write!(f, "(")?;
+                    let mut _n = 0;
+                    $(if _n != 0 { write!(f, " | ")?; } write!(f, "{}", $ty::annotation())?; _n += 1;)*
+                    write!(f, ")")
+                })
+            }
+        }
+    };
+}
+
+impl_oneof!(A, B);
+impl_oneof!(A, B, C);
+impl_oneof!(A, B, C, D);
+impl_oneof!(A, B, C, D, E);
+impl_oneof!(A, B, C, D, E, F);
+impl_oneof!(A, B, C, D, E, F, G);
+impl_oneof!(A, B, C, D, E, F, G, H);
+impl_oneof!(A, B, C, D, E, F, G, H, I);
+
+impl<T> Annotate for Option<T>
+where
+    T: Annotate,
+{
+    fn annotation() -> impl Display {
+        display!("{}?", T::annotation())
+    }
+}
+
+impl<T, E> Annotate for Result<T, E>
+where
+    T: Annotate,
+{
+    fn annotation() -> impl Display {
+        display!("{}", T::annotation())
+    }
+}

crates/luaffi/src/option.rs

@@ -0,0 +1,89 @@
+use crate::{
+    __internal::{disp, display, type_id},
+    Cdef, CdefBuilder, IntoFfi, KEEP_FN, Metatype, MetatypeBuilder, Type, TypeBuilder, TypeType,
+};
+use std::{ffi::c_int, fmt::Display};
+
+#[repr(C)]
+#[allow(non_camel_case_types)]
+pub enum lua_option<T> {
+    None,    // __tag = 0
+    Some(T), // __tag = 1
+}
+
+unsafe impl<T: Type + 'static> Type for lua_option<T> {
+    fn name() -> impl Display {
+        display!("__option_{:x}", type_id::<T>())
+    }
+
+    fn ty() -> TypeType {
+        TypeType::Aggregate
+    }
+
+    fn cdecl(name: impl Display) -> impl Display {
+        display!("struct {} {name}", Self::name())
+    }
+
+    fn build(b: &mut TypeBuilder) {
+        b.cdef::<Self>().metatype::<Self>();
+    }
+}
+
+unsafe impl<T: Type + 'static> Cdef for lua_option<T> {
+    fn build(b: &mut CdefBuilder) {
+        b.field::<c_int>("__tag");
+        (T::ty() != TypeType::Void).then(|| b.field::<T>("__value"));
+    }
+}
+
+unsafe impl<T: Type + 'static> Metatype for lua_option<T> {
+    type Target = Self;
+    fn build(_b: &mut MetatypeBuilder) {}
+}
+
+unsafe impl<T: IntoFfi<Into: 'static>> IntoFfi for Option<T> {
+    type Into = lua_option<T::Into>;
+
+    fn convert(self) -> Self::Into {
+        match self {
+            Some(value) => lua_option::Some(T::convert(value)),
+            None => lua_option::None,
+        }
+    }
+
+    fn require_owned() -> bool {
+        // lua_option is only used to transmit information about whether we have a value or not and
+        // is forgotten immediately after use, so there is no need for an owned option
+        false
+    }
+
+    fn postlude(ret: &str) -> impl Display {
+        disp(move |f| {
+            write!(f, "if {ret}.__tag ~= 0 then ")?;
+            match T::Into::ty() {
+                TypeType::Void => write!(f, "{ret} = nil; ")?, // for void options, we don't have a __value
+                TypeType::Primitive => {
+                    // can always copy primitives to stack
+                    write!(f, "{ret} = {ret}.__value; {}", T::postlude(ret))?;
+                }
+                TypeType::Aggregate => {
+                    let ct = T::Into::name();
+                    if T::require_owned() {
+                        // inner value requires ownership; copy it into its own cdata and forget
+                        // option.
+                        write!(f, "{ret} = __new(__ct.{ct}, {ret}.__value); ")?;
+                        write!(f, "{}", T::postlude(ret))?;
+                    } else {
+                        // inner value is a "temporary" like an option itself and doesn't require
+                        // full ownership of itself. we just need to keep the option object alive
+                        // until its postlude completes.
+                        write!(f, "local {ret}_keep = {ret}; {ret} = {ret}.__value; ")?;
+                        write!(f, "do {}end; ", T::postlude(ret))?;
+                        write!(f, "__C.{KEEP_FN}({ret}_keep); ")?; // keep original option alive
+                    }
+                }
+            }
+            write!(f, "else {ret} = nil; end; ")
+        })
+    }
+}

crates/luaffi/src/result.rs

@@ -1,6 +1,6 @@
 use crate::{
-    __internal::{disp, display},
-    Cdef, CdefBuilder, IntoFfi, Type, TypeBuilder, TypeType,
+    __internal::{disp, display, type_id},
+    Cdef, CdefBuilder, IntoFfi, KEEP_FN, Metatype, MetatypeBuilder, Type, TypeBuilder, TypeType,
     string::{DROP_BUFFER_FN, lua_buffer},
 };
 use std::{ffi::c_int, fmt::Display};
@@ -12,9 +12,9 @@ pub enum lua_result<T> {
     Ok(T),           // __tag = 1
 }
 
-unsafe impl<T: Type> Type for lua_result<T> {
+unsafe impl<T: Type + 'static> Type for lua_result<T> {
     fn name() -> impl Display {
-        display!("result__{}", T::name())
+        display!("__result_{:x}", type_id::<T>())
     }
 
     fn ty() -> TypeType {
@@ -26,11 +26,11 @@ unsafe impl<T: Type> Type for lua_result<T> {
     }
 
     fn build(b: &mut TypeBuilder) {
-        b.cdef::<Self>();
+        b.cdef::<Self>().metatype::<Self>();
     }
 }
 
-unsafe impl<T: Type> Cdef for lua_result<T> {
+unsafe impl<T: Type + 'static> Cdef for lua_result<T> {
     fn build(b: &mut CdefBuilder) {
         b.field::<c_int>("__tag").inner_union(|b| {
             (T::ty() != TypeType::Void).then(|| b.field::<T>("__value"));
@@ -39,7 +39,12 @@ unsafe impl<T: Type> Cdef for lua_result<T> {
     }
 }
 
-unsafe impl<T: IntoFfi, E: Display> IntoFfi for Result<T, E> {
+unsafe impl<T: Type + 'static> Metatype for lua_result<T> {
+    type Target = Self;
+    fn build(_b: &mut MetatypeBuilder) {}
+}
+
+unsafe impl<T: IntoFfi<Into: 'static>, E: Display> IntoFfi for Result<T, E> {
     type Into = lua_result<T::Into>;
 
     fn convert(self) -> Self::Into {
@@ -49,22 +54,44 @@ unsafe impl<T: IntoFfi, E: Display> IntoFfi for Result<T, E> {
         }
     }
 
+    fn require_owned() -> bool {
+        // lua_result is only used to transmit information about whether an operation succeeded or
+        // not and is forgotten immediately after use, so there is no need for an owned result
+        false
+    }
+
     fn postlude(ret: &str) -> impl Display {
         disp(move |f| {
-            let ct = T::Into::name();
             write!(f, "if {ret}.__tag ~= 0 then ")?;
             match T::Into::ty() {
-                TypeType::Void => write!(f, "{ret} = nil; "), // for void results, we don't have a __value
-                TypeType::Primitive => write!(f, "{ret} = {ret}.__value; "),
-                TypeType::Aggregate => write!(f, "{ret} = __new(__ct.{ct}, {ret}.__value); "),
-            }?;
-            write!(f, "{}", T::postlude(ret))?;
+                TypeType::Void => write!(f, "{ret} = nil; ")?, // for void results, we don't have a __value
+                TypeType::Primitive => {
+                    // can always copy primitives to stack
+                    write!(f, "{ret} = {ret}.__value; {}", T::postlude(ret))?;
+                }
+                TypeType::Aggregate => {
+                    let ct = T::Into::name();
+                    if T::require_owned() {
+                        // inner value requires ownership; copy it into its own cdata and forget
+                        // result.
+                        write!(f, "{ret} = __new(__ct.{ct}, {ret}.__value); ")?;
+                        write!(f, "{}", T::postlude(ret))?;
+                    } else {
+                        // inner value is a "temporary" like a result itself and doesn't require
+                        // full ownership of itself. we just need to keep the result object alive
+                        // until its postlude completes.
+                        write!(f, "local {ret}_keep = {ret}; {ret} = {ret}.__value; ")?;
+                        write!(f, "do {}end; ", T::postlude(ret))?;
+                        write!(f, "__C.{KEEP_FN}({ret}_keep); ")?; // keep original result alive
+                    }
+                }
+            }
             write!(
                 f,
                 "else \
-                    local __{ret}_msg = __intern({ret}.__err.__ptr, {ret}.__err.__len); \
+                    local {ret}_err = __intern({ret}.__err.__ptr, {ret}.__err.__len); \
                     __C.{DROP_BUFFER_FN}({ret}.__err); \
-                    return error(__{ret}_msg); \
+                    return error({ret}_err); \
                  end; "
             )
         })

crates/luaffi/src/string.rs

@@ -4,18 +4,18 @@ use crate::{
 };
 use bstr::{BStr, BString};
 use luaffi_impl::{cdef, metatype};
-use std::{fmt::Display, mem::ManuallyDrop, ptr, slice};
+use std::{fmt::Display, mem::ManuallyDrop, slice};
 
-pub(crate) const IS_UTF8_FN: &str = "luaffi_is_utf8";
-pub(crate) const DROP_BUFFER_FN: &str = "luaffi_drop_buffer";
+pub(crate) const IS_UTF8_FN: &str = "__lf_is_utf8";
+pub(crate) const DROP_BUFFER_FN: &str = "__lf_drop_buffer";
 
-#[unsafe(export_name = "luaffi_is_utf8")]
+#[unsafe(export_name = "__lf_is_utf8")]
 unsafe extern "C" fn __is_utf8(ptr: *const u8, len: usize) -> bool {
     debug_assert!(!ptr.is_null());
     simdutf8::basic::from_utf8(unsafe { slice::from_raw_parts(ptr, len) }).is_ok()
 }
 
-#[unsafe(export_name = "luaffi_drop_buffer")]
+#[unsafe(export_name = "__lf_drop_buffer")]
 unsafe extern "C" fn __drop_buffer(buf: *mut lua_buffer) {
     debug_assert!(!buf.is_null());
     debug_assert!(!unsafe { (*buf).__ptr.is_null() });
@@ -42,6 +42,7 @@ impl lua_buf {
         }
     }
 
+    #[cfg(feature = "option_string_abi")]
     pub(crate) fn null() -> Self {
         Self {
             __ptr: ptr::null(),
@@ -71,6 +72,7 @@ impl lua_buffer {
         }
     }
 
+    #[cfg(feature = "option_string_abi")]
     pub(crate) fn null() -> Self {
         Self {
             __ptr: ptr::null_mut(),
@@ -154,8 +156,14 @@ unsafe impl IntoFfi for &'static [u8] {
         lua_buf::new(self)
     }
 
+    fn require_owned() -> bool {
+        // lua_buf is only used to have its contents interned then forgotten immediately; no need
+        // for ownership of it
+        false
+    }
+
     fn postlude(ret: &str) -> impl Display {
-        display!("{ret} = __intern({ret}.__ptr, {ret}.__len)")
+        display!("{ret} = __intern({ret}.__ptr, {ret}.__len); ")
     }
 }
 
@@ -166,9 +174,15 @@ unsafe impl IntoFfi for Vec<u8> {
         lua_buffer::new(self)
     }
 
+    fn require_owned() -> bool {
+        // lua_buffer is only used to have its contents interned then forgotten immediately; no need
+        // for ownership of it
+        false
+    }
+
     fn postlude(ret: &str) -> impl Display {
         display!(
-            "do local __{ret} = {ret}; {ret} = __intern({ret}.__ptr, {ret}.__len); __C.{DROP_BUFFER_FN}(__{ret}); end; "
+            "local {ret}_buf = {ret}; {ret} = __intern({ret}.__ptr, {ret}.__len); __C.{DROP_BUFFER_FN}({ret}_buf); "
         )
     }
 }
@@ -216,56 +230,64 @@ impl_into_via!(&'static str, &'static BStr);
 impl_into_via!(BString, Vec<u8>);
 impl_into_via!(String, BString);
 
-macro_rules! impl_optional_from {
-    ($ty:ty) => {
-        unsafe impl<'s> FromFfi for Option<$ty> {
-            type From = <$ty as FromFfi>::From;
+// `Option<String>: From/IntoFfi` isn't implemented because it conflicts with the generic
+// `Option<T>: From/IntoFfi` impl and rust doesn't have specialisation yet (and probably not anytime
+// soon). this is fine for now because we have specialisation for string-like parameters implemented
+// in the #[metatype] macro already, and string returns wrapped in `Option<T>` isn't much additional
+// overhead.
+#[cfg(feature = "option_string_abi")]
+mod impl_option_string {
+    macro_rules! impl_optional_from {
+        ($ty:ty) => {
+            unsafe impl<'s> FromFfi for Option<$ty> {
+                type From = <$ty as FromFfi>::From;
 
-            fn require_keepalive() -> bool {
-                <$ty as FromFfi>::require_keepalive()
-            }
+                fn require_keepalive() -> bool {
+                    <$ty as FromFfi>::require_keepalive()
+                }
 
-            fn prelude(arg: &str) -> impl Display {
-                // just pass a null pointer if argument is nil
-                display!(
-                    "if {arg} ~= nil then {}end; ",
-                    <$ty as FromFfi>::prelude(arg)
-                )
-            }
+                fn prelude(arg: &str) -> impl Display {
+                    // just pass a null pointer if argument is nil
+                    display!(
+                        "if {arg} ~= nil then {}end; ",
+                        <$ty as FromFfi>::prelude(arg)
+                    )
+                }
 
-            fn convert(from: Self::From) -> Self {
-                from.map(|s| <$ty as FromFfi>::convert(Some(s)))
+                fn convert(from: Self::From) -> Self {
+                    from.map(|s| <$ty as FromFfi>::convert(Some(s)))
+                }
             }
-        }
-    };
+        };
+    }
+
+    impl_optional_from!(&'s [u8]);
+    impl_optional_from!(&'s BStr);
+    impl_optional_from!(&'s str);
+
+    macro_rules! impl_optional_into {
+        ($ty:ty, $null:expr) => {
+            unsafe impl IntoFfi for Option<$ty> {
+                type Into = <$ty as IntoFfi>::Into;
+
+                fn convert(self) -> Self::Into {
+                    self.map_or($null, <$ty as IntoFfi>::convert)
+                }
+
+                fn postlude(ret: &str) -> impl Display {
+                    display!(
+                        "if {ret}.__ptr == nil then {ret} = nil; else {}end; ",
+                        <$ty as IntoFfi>::postlude(ret)
+                    )
+                }
+            }
+        };
+    }
+
+    impl_optional_into!(&'static [u8], lua_buf::null());
+    impl_optional_into!(&'static BStr, lua_buf::null());
+    impl_optional_into!(&'static str, lua_buf::null());
+    impl_optional_into!(Vec<u8>, lua_buffer::null());
+    impl_optional_into!(BString, lua_buffer::null());
+    impl_optional_into!(String, lua_buffer::null());
 }
-
-impl_optional_from!(&'s [u8]);
-impl_optional_from!(&'s BStr);
-impl_optional_from!(&'s str);
-
-macro_rules! impl_optional_into {
-    ($ty:ty, $null:expr) => {
-        unsafe impl IntoFfi for Option<$ty> {
-            type Into = <$ty as IntoFfi>::Into;
-
-            fn convert(self) -> Self::Into {
-                self.map_or($null, <$ty as IntoFfi>::convert)
-            }
-
-            fn postlude(ret: &str) -> impl Display {
-                display!(
-                    "if {ret}.__ptr == nil then {ret} = nil; else {}end; ",
-                    <$ty as IntoFfi>::postlude(ret)
-                )
-            }
-        }
-    };
-}
-
-impl_optional_into!(&'static [u8], lua_buf::null());
-impl_optional_into!(&'static BStr, lua_buf::null());
-impl_optional_into!(&'static str, lua_buf::null());
-impl_optional_into!(Vec<u8>, lua_buffer::null());
-impl_optional_into!(BString, lua_buffer::null());
-impl_optional_into!(String, lua_buffer::null());

crates/luaffi_impl/Cargo.toml

@@ -1,7 +1,11 @@
 [package]
 name = "luaffi_impl"
-version = "0.1.0"
-edition = "2024"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
 
 [lib]
 proc-macro = true

crates/luaffi_impl/src/cdef.rs

@@ -5,18 +5,26 @@ use quote::{format_ident, quote, quote_spanned};
 use syn::{ext::IdentExt, spanned::Spanned, *};
 
 #[derive(Debug, FromMeta)]
-pub struct Args {}
+pub struct Args {
+    module: Option<String>,
+}
 
-pub fn transform(_args: Args, mut item: Item) -> Result<TokenStream> {
-    let (name, impl_type, impl_cdef) = match item {
+pub fn transform(args: Args, mut item: Item) -> Result<TokenStream> {
+    let (name, impl_type, impl_module, impl_cdef) = match item {
         Item::Struct(ref mut str) => (
             str.ident.clone(),
             generate_type(&str.ident)?,
+            args.module
+                .map(|name| generate_module(&name, &str.ident))
+                .transpose()?,
             generate_cdef_structure(str)?,
         ),
         Item::Enum(ref mut enu) => (
             enu.ident.clone(),
             generate_type(&enu.ident)?,
+            args.module
+                .map(|name| generate_module(&name, &enu.ident))
+                .transpose()?,
             generate_cdef_enum(enu)?,
         ),
         _ => syn_error!(item, "expected struct or enum"),
@@ -35,6 +43,7 @@ pub fn transform(_args: Args, mut item: Item) -> Result<TokenStream> {
         mod #mod_name {
             use super::*;
             #impl_type
+            #impl_module
             #impl_cdef
         }
     ))
@@ -42,14 +51,11 @@ pub fn transform(_args: Args, mut item: Item) -> Result<TokenStream> {
 
 fn generate_type(ty: &Ident) -> Result<TokenStream> {
     let ffi = ffi_crate();
-    let span = ty.span();
-    let name = LitStr::new(&ty.unraw().to_string(), span);
+    let name = ty.unraw().to_string();
 
-    Ok(quote_spanned!(span =>
+    Ok(quote!(
         unsafe impl #ffi::Type for #ty {
-            fn name() -> impl ::std::fmt::Display {
-                #name
-            }
+            fn name() -> impl ::std::fmt::Display { #name }
 
             fn ty() -> #ffi::TypeType {
                 #ffi::TypeType::Aggregate
@@ -64,6 +70,10 @@ fn generate_type(ty: &Ident) -> Result<TokenStream> {
             }
         }
 
+        impl #ffi::Annotate for #ty {
+            fn annotation() -> impl ::std::fmt::Display { #name }
+        }
+
         // SAFETY: we can always implement `IntoFfi` because it transfers ownership from Rust to Lua
         unsafe impl #ffi::IntoFfi for #ty {
             type Into = Self;
@@ -72,6 +82,16 @@ fn generate_type(ty: &Ident) -> Result<TokenStream> {
     ))
 }
 
+fn generate_module(name: &str, ty: &Ident) -> Result<TokenStream> {
+    let ffi = ffi_crate();
+
+    Ok(quote!(
+        impl #ffi::Module for #ty {
+            fn name() -> impl ::std::fmt::Display { #name }
+        }
+    ))
+}
+
 fn generate_cdef_structure(str: &mut ItemStruct) -> Result<TokenStream> {
     syn_assert!(
         str.generics.params.is_empty(),
@@ -81,10 +101,9 @@ fn generate_cdef_structure(str: &mut ItemStruct) -> Result<TokenStream> {
 
     let ffi = ffi_crate();
     let ty = &str.ident;
-    let span = ty.span();
-    let build = generate_cdef_build(&get_cfields(&mut str.fields)?)?;
+    let build = generate_cdef_build(&parse_cfields(&mut str.fields)?)?;
 
-    Ok(quote_spanned!(span =>
+    Ok(quote!(
         unsafe impl #ffi::Cdef for #ty {
             fn build(b: &mut #ffi::CdefBuilder) { #build }
         }
@@ -100,18 +119,16 @@ fn generate_cdef_enum(enu: &mut ItemEnum) -> Result<TokenStream> {
 
     let ffi = ffi_crate();
     let ty = &enu.ident;
-    let span = ty.span();
     let build = enu
         .variants
         .iter_mut()
         .map(|variant| {
-            let span = variant.span();
-            let build = generate_cdef_build(&get_cfields(&mut variant.fields)?)?;
-            Ok(quote_spanned!(span => b.inner_struct(|b| { #build })))
+            let build = generate_cdef_build(&parse_cfields(&mut variant.fields)?)?;
+            Ok(quote!(b.inner_struct(|b| { #build })))
         })
         .collect::<Result<Vec<_>>>()?;
 
-    Ok(quote_spanned!(span =>
+    Ok(quote!(
         unsafe impl #ffi::Cdef for #ty {
             fn build(b: &mut #ffi::CdefBuilder) {
                 b.field::<::std::ffi::c_int>("__tag").inner_union(|b| { #(#build;)* });
@@ -131,7 +148,7 @@ struct CFieldAttrs {
     opaque: bool,
 }
 
-fn get_cfields(fields: &mut Fields) -> Result<Vec<CField>> {
+fn parse_cfields(fields: &mut Fields) -> Result<Vec<CField>> {
     match fields {
         Fields::Named(fields) => fields.named.iter_mut(),
         Fields::Unnamed(fields) => fields.unnamed.iter_mut(),
@@ -155,12 +172,11 @@ fn parse_cfield_attrs(attrs: &mut Vec<Attribute>) -> Result<CFieldAttrs> {
     let mut parsed = CFieldAttrs::default();
     let mut i = 0;
     while let Some(attr) = attrs.get(i) {
-        if let Some(name) = attr.path().get_ident() {
-            if name == "opaque" {
-                parsed.opaque = true;
-                attrs.remove(i);
-                continue;
-            }
+        let path = attr.path();
+        if path.is_ident("opaque") {
+            parsed.opaque = true;
+            attrs.remove(i);
+            continue;
         }
         i += 1;
     }
@@ -185,7 +201,7 @@ fn generate_cdef_build(fields: &[CField]) -> Result<TokenStream> {
     for (i, field) in fields.iter().enumerate() {
         let ty = &field.ty;
         let offset = offset(i);
-        body.push(quote_spanned!(ty.span() =>
+        body.push(quote!(
             // round up current offset to the alignment of field type for field offset
             offset = (offset + #align_of::<#ty>() - 1) & !(#align_of::<#ty>() - 1);
             align = #max(align, #align_of::<#ty>());

crates/luaffi_impl/src/lib.rs

@@ -1,7 +1,6 @@
 use darling::{FromMeta, ast::NestedMeta};
 use proc_macro::TokenStream as TokenStream1;
 use quote::ToTokens;
-use syn::parse_macro_input;
 
 mod cdef;
 mod metatype;
@@ -17,8 +16,10 @@ pub fn cdef(args: TokenStream1, input: TokenStream1) -> TokenStream1 {
 }
 
 #[proc_macro_attribute]
-pub fn metatype(_args: TokenStream1, input: TokenStream1) -> TokenStream1 {
-    metatype::transform(parse_macro_input!(input))
+pub fn metatype(args: TokenStream1, input: TokenStream1) -> TokenStream1 {
+    NestedMeta::parse_meta_list(args.into())
+        .and_then(|meta| metatype::Args::from_list(&meta).map_err(Into::into))
+        .and_then(|args| metatype::transform(args, syn::parse(input)?))
         .unwrap_or_else(|err| err.into_compile_error().into_token_stream())
         .into()
 }

crates/luaffi_impl/src/utils.rs

@@ -1,5 +1,5 @@
 use std::env;
-use syn::{spanned::Spanned, *};
+use syn::{ext::IdentExt, spanned::Spanned, *};
 
 macro_rules! syn_error {
     ($src:expr, $($fmt:expr),+) => {{
@@ -57,13 +57,13 @@ pub fn is_unit(ty: &Type) -> bool {
 
 pub fn is_primitivelike(ty: &Type) -> bool {
     match ty {
-        Type::Tuple(tuple) if tuple.elems.is_empty() => true, // unit type
-        Type::Reference(_) | Type::Ptr(_) => true,
-        Type::Paren(paren) => is_primitivelike(&paren.elem),
+        Type::Tuple(tuple) if tuple.elems.is_empty() => return true, // unit type
+        Type::Reference(_) | Type::Ptr(_) => return true,
+        Type::Paren(paren) => return is_primitivelike(&paren.elem),
         Type::Path(path) => {
             if let Some(name) = path.path.get_ident() {
-                matches!(
-                    format!("{name}").as_str(),
+                return matches!(
+                    name.unraw().to_string().as_str(),
                     "bool"
                         | "u8"
                         | "u16"
@@ -94,11 +94,88 @@ pub fn is_primitivelike(ty: &Type) -> bool {
                         | "c_size_t"
                         | "c_ssize_t"
                         | "c_ptrdiff_t"
-                )
-            } else {
-                false
+                );
             }
         }
-        _ => false,
+        _ => {}
+    }
+
+    false
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum StringLike {
+    SliceU8,
+    Str,
+    BStr,
+}
+
+pub fn is_stringlike(ty: &Type) -> Option<StringLike> {
+    if let Type::Reference(ty) = ty
+        && ty.mutability.is_none()
+        && ty.lifetime.is_none()
+    {
+        Some(match *ty.elem {
+            Type::Slice(ref slice) => {
+                // match &[u8]
+                if let Type::Path(ref path) = *slice.elem
+                    && let Some(name) = path.path.get_ident()
+                {
+                    match name.unraw().to_string().as_str() {
+                        "u8" => StringLike::SliceU8,
+                        _ => return None,
+                    }
+                } else {
+                    return None;
+                }
+            }
+            Type::Path(ref path) => {
+                // match &str or &BStr
+                if let Some(name) = path.path.get_ident() {
+                    match name.unraw().to_string().as_str() {
+                        "str" => StringLike::Str,
+                        "BStr" => StringLike::BStr,
+                        _ => return None,
+                    }
+                } else {
+                    return None;
+                }
+            }
+            _ => return None,
+        })
+    } else {
+        None
+    }
+}
+
+pub fn is_optionlike(ty: &Type) -> Option<&Type> {
+    if let Type::Path(path) = ty
+        && path.path.leading_colon.is_none()
+        && path.path.segments.len() == 1
+        && let Some(segment) = path.path.segments.get(0)
+        && segment.ident == "Option"
+        && let PathArguments::AngleBracketed(ref angle) = segment.arguments
+        && angle.args.len() == 1
+        && let Some(GenericArgument::Type(ty)) = angle.args.get(0)
+    {
+        Some(ty)
+    } else {
+        None
+    }
+}
+
+pub fn is_resultlike(ty: &Type) -> Option<&Type> {
+    if let Type::Path(path) = ty
+        && path.path.leading_colon.is_none()
+        && path.path.segments.len() == 1
+        && let Some(segment) = path.path.segments.get(0)
+        && segment.ident == "Result"
+        && let PathArguments::AngleBracketed(ref angle) = segment.arguments
+        && angle.args.len() <= 2 // allow Result<T, E> or Result<T>
+        && let Some(GenericArgument::Type(ty)) = angle.args.get(0)
+    {
+        Some(ty)
+    } else {
+        None
     }
 }

crates/luaify/Cargo.toml

@@ -1,7 +1,11 @@
 [package]
 name = "luaify"
-version = "0.1.0"
-edition = "2024"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
 
 [lib]
 proc-macro = true
@@ -10,3 +14,6 @@ proc-macro = true
 proc-macro2 = "1.0.95"
 quote = "1.0.40"
 syn = { version = "2.0.103", features = ["full", "visit-mut"] }
+
+[dev-dependencies]
+pretty_assertions = "1.4.1"

crates/luaify/src/generate.rs

@@ -14,6 +14,12 @@ pub fn generate(expr: &Expr) -> Result<TokenStream> {
     Ok(f.done())
 }
 
+pub fn generate_chunk(block: &Block) -> Result<TokenStream> {
+    let mut f = Formatter::default();
+    generate_block(&mut f, &block, Context::stmt(false))?;
+    Ok(f.done())
+}
+
 #[derive(Default)]
 struct Formatter {
     buf: String,
@@ -910,7 +916,7 @@ fn generate_pat_typed(f: &mut Formatter, typed: &PatType, cx: PatContext) -> Res
     assert_no_attrs!(typed);
     match *typed.ty {
         Type::Infer(_) => generate_pat(f, &typed.pat, cx),
-        ref ty => syn_error!(ty, "cannot have type"),
+        ref ty => syn_error!(ty, "cannot specify type"),
     }
 }
 

crates/luaify/src/lib.rs

@@ -1,4 +1,57 @@
-use crate::{generate::generate, transform::transform};
+//! # luaify
+//!
+//! A macro for generating Lua code from Rust syntax.
+//!
+//! This macro performs a direct one-to-one translation of Rust expressions and blocks into
+//! equivalent Lua code. For example,
+//!
+//! ```rust
+//! use luaify::luaify;
+//!
+//! luaify!(|a, b| {
+//!     let c = a + b;
+//!
+//!     fn inner_function(c: _) {
+//!         print(concat!("the sum of ", a, " and ", b, " is ", c));
+//!         c
+//!     }
+//!
+//!     inner_function(c);
+//! });
+//! ```
+//!
+//! will translate to the following equivalent Lua code (embedded as an [`&str`] or [`String`] in
+//! Rust):
+//!
+//! ```lua
+//! function(a, b)
+//!     local c = a + b
+//!
+//!     local function inner_function(c)
+//!         print("the sum of " .. a .. " and " .. b .. " is " .. c)
+//!         return c
+//!     end
+//!
+//!     inner_function(c)
+//! end
+//! ```
+//!
+//! This macro accepts a smaller subset of all valid Rust syntax due to the difference between
+//! Rust's expression-based syntax and Lua's statement-based syntax. Most Rust syntax are translated
+//! to their equivalents in Lua, however the following features are not supported and will result in
+//! a compile-time error:
+//!
+//! - static typing (typed local variables, parameters and return types in function signatures,
+//!   etc.)
+//! - pattern matching (e.g. `match`, `if let`, `while let`)
+//! - items other than statements or functions (e.g. `struct`, `enum`, `trait`, `impl`)
+//! - block statements in expression position (e.g. `if`, `while`, `for`, `loop` that evaluate to a
+//!   value)
+//! - expressions in statement position (except for function calls and assignments)
+use crate::{
+    generate::{generate, generate_chunk},
+    transform::{transform, transform_chunk},
+};
 use proc_macro::TokenStream as TokenStream1;
 use quote::ToTokens;
 use syn::parse_macro_input;
@@ -7,6 +60,7 @@ mod generate;
 mod transform;
 mod utils;
 
+/// Generates Lua code for the given expression.
 #[proc_macro]
 pub fn luaify(input: TokenStream1) -> TokenStream1 {
     let mut expr = parse_macro_input!(input);
@@ -16,3 +70,14 @@ pub fn luaify(input: TokenStream1) -> TokenStream1 {
     }
     .into()
 }
+
+/// Generates Lua code for the given block.
+#[proc_macro]
+pub fn luaify_chunk(input: TokenStream1) -> TokenStream1 {
+    let mut block = parse_macro_input!(input);
+    match transform_chunk(&mut block).and_then(|()| generate_chunk(&block)) {
+        Ok(s) => s,
+        Err(err) => err.into_compile_error().into_token_stream(),
+    }
+    .into()
+}

crates/luaify/src/transform.rs

@@ -1,6 +1,4 @@
-use crate::utils::{LuaType, expr_ident, pat_ident, syn_error, wrap_expr_block};
-use quote::format_ident;
-use std::mem;
+use crate::utils::syn_error;
 use syn::{spanned::*, visit_mut::*, *};
 
 pub fn transform(expr: &mut Expr) -> Result<()> {
@@ -9,6 +7,12 @@ pub fn transform(expr: &mut Expr) -> Result<()> {
     visitor.result
 }
 
+pub fn transform_chunk(block: &mut Block) -> Result<()> {
+    let mut visitor = Visitor::new();
+    visitor.visit_block_mut(block);
+    visitor.result
+}
+
 #[derive(Debug)]
 struct Visitor {
     result: Result<()>,
@@ -21,27 +25,6 @@ impl Visitor {
 }
 
 impl VisitMut for Visitor {
-    fn visit_expr_closure_mut(&mut self, clo: &mut ExprClosure) {
-        match self.transform_expr_closure(clo) {
-            res @ Err(_) => self.result = res,
-            _ => visit_expr_closure_mut(self, clo),
-        }
-    }
-
-    fn visit_item_fn_mut(&mut self, func: &mut ItemFn) {
-        match self.transform_function(func) {
-            res @ Err(_) => self.result = res,
-            _ => visit_item_fn_mut(self, func),
-        }
-    }
-
-    fn visit_expr_mut(&mut self, expr: &mut Expr) {
-        match self.transform_expr(expr) {
-            res @ Err(_) => self.result = res,
-            _ => visit_expr_mut(self, expr),
-        }
-    }
-
     fn visit_expr_unary_mut(&mut self, un: &mut ExprUnary) {
         match self.transform_unary(un) {
             res @ Err(_) => self.result = res,
@@ -58,147 +41,9 @@ impl VisitMut for Visitor {
 }
 
 impl Visitor {
-    fn transform_expr_closure(&mut self, clo: &mut ExprClosure) -> Result<()> {
-        //
-        // transforms a closure expression with input type annotations by removing the annotations
-        // and inserting `as` casts at the start.
-        //
-        // before:
-        //    |a: string, b: number| { ... }
-        // after:
-        //    |a, b| { a as string; b as number; ... }
-        //
-        let mut checks: Vec<Stmt> = vec![];
-        for input in clo.inputs.iter_mut() {
-            match input {
-                Pat::Ident(_) => {}
-                Pat::Type(typed) => {
-                    let ident = pat_ident(&typed.pat)?;
-                    let ty = mem::replace(&mut typed.ty, parse_quote!(_));
-                    match (&*ty).try_into()? {
-                        LuaType::Any => {}
-                        _ => checks.push(parse_quote! { #ident as #ty; }),
-                    }
-                }
-                _ => {}
-            }
-        }
-
-        if !checks.is_empty() {
-            let mut body = wrap_expr_block(&clo.body);
-            body.stmts.splice(..0, checks);
-            clo.body = Box::new(parse_quote! { #body });
-        }
-
-        Ok(())
-    }
-
-    fn transform_function(&mut self, func: &mut ItemFn) -> Result<()> {
-        //
-        // transforms a function item with input type annotations by removing the annotations
-        // and inserting `as` casts at the start.
-        //
-        // before:
-        //    fn my_func(self: table, a: string) { ... }
-        // after:
-        //    fn my_func(self: _, a: _) { self as table; a as string; ... }
-        //
-        let mut checks: Vec<Stmt> = vec![];
-        for input in func.sig.inputs.iter_mut() {
-            if let Some((ident, ty)) = match input {
-                FnArg::Receiver(recv) if recv.colon_token.is_some() => {
-                    let ty = mem::replace(&mut recv.ty, parse_quote!(_));
-                    recv.colon_token = None;
-                    Some((Ident::new("self", recv.self_token.span()), ty))
-                }
-                FnArg::Typed(typed) => {
-                    let ident = pat_ident(&typed.pat)?;
-                    let ty = mem::replace(&mut typed.ty, parse_quote!(_));
-                    Some((ident, ty))
-                }
-                _ => None,
-            } {
-                match (&*ty).try_into()? {
-                    LuaType::Any => {}
-                    _ => checks.push(parse_quote! { #ident as #ty; }),
-                }
-            };
-        }
-
-        func.block.stmts.splice(..0, checks);
-        Ok(())
-    }
-
-    fn transform_expr(&mut self, expr: &mut Expr) -> Result<()> {
-        self.transform_expr_cast(expr)?;
-        Ok(())
-    }
-
-    fn transform_expr_cast(&mut self, expr: &mut Expr) -> Result<()> {
-        //
-        // transforms an `as` cast expression into a block expression containing a runtime
-        // lua type check.
-        //
-        // before:
-        //    var as string
-        // after:
-        //    { if type(var) != "string" { error(...) } }
-        //
-        if let Expr::Cast(cast) = expr {
-            let arg = (*cast.expr).clone();
-            let mut prelude: Option<Stmt> = None;
-            let ty: LuaType = (&*cast.ty).try_into()?;
-            let ty_str = format!("{ty}");
-            let (ident, msg) = match expr_ident(&arg) {
-                Ok(ident) => (ident.clone(), format!("{ty} expected in '{ident}', got ")),
-                Err(_) => {
-                    let ident = Ident::new("_", arg.span());
-                    prelude = Some(parse_quote! { let #ident = #arg; });
-                    (ident, format!("{ty} expected, got "))
-                }
-            };
-
-            let tmp = format_ident!("__{ident}");
-            let span = cast.span();
-            *expr = match ty {
-                LuaType::Any => parse_quote_spanned!(span => {}),
-                LuaType::Nil => parse_quote_spanned!(span => {
-                    #prelude
-                    assert(#ident == (), concat!(#msg, r#type(#ident)));
-                }),
-                LuaType::Number => parse_quote_spanned!(span => {
-                    #prelude
-                    let #tmp = #ident;
-                    #ident = tonumber(#ident);
-                    assert(#ident != (), concat!(#msg, r#type(#tmp)));
-                }),
-                LuaType::Integer => parse_quote_spanned!(span => {
-                    #prelude
-                    let #tmp = #ident;
-                    #ident = tonumber(#ident);
-                    assert(#ident != () && math::floor(#ident) == #ident, concat!(#msg, r#type(#tmp)));
-                }),
-                LuaType::String => parse_quote_spanned!(span => {
-                    #prelude
-                    if r#type(#ident) == "number" {
-                        #ident = tostring(#ident);
-                    } else {
-                        assert(r#type(#ident) == "string", concat!(#msg, r#type(#ident)));
-                    }
-                }),
-                _ => parse_quote_spanned!(span => {
-                    #prelude
-                    assert(r#type(#ident) == #ty_str, concat!(#msg, r#type(#ident)));
-                }),
-            }
-        }
-
-        Ok(())
-    }
-
     fn transform_unary(&mut self, un: &mut ExprUnary) -> Result<()> {
         //
-        // separates a nested negation unary operator with parentheses, because double hyphen
+        // separates a nested negation unary operator with parentheses, because the double hyphen
         // `--` indicates a comment in lua.
         //
         // before:
@@ -210,7 +55,7 @@ impl Visitor {
             && let Expr::Unary(ref inner) = *un.expr
             && let UnOp::Neg(_) = inner.op
         {
-            un.expr = Box::new(parse_quote!((#inner)));
+            un.expr = Box::new(parse_quote_spanned!(inner.span() => (#inner)));
         }
 
         Ok(())

crates/luaify/src/utils.rs

@@ -1,5 +1,4 @@
-use std::fmt;
-use syn::{ext::*, spanned::*, *};
+use syn::*;
 
 macro_rules! syn_error {
     ($src:expr, $($fmt:expr),+) => {{
@@ -24,90 +23,3 @@ pub fn wrap_expr_block(expr: &Expr) -> Block {
         expr => parse_quote!({ #expr }),
     }
 }
-
-pub fn expr_ident(expr: &Expr) -> Result<&Ident> {
-    match expr {
-        Expr::Path(path) => path.path.require_ident(),
-        _ => syn_error!(expr, "expected ident"),
-    }
-}
-
-pub fn pat_ident(pat: &Pat) -> Result<Ident> {
-    Ok(match pat {
-        Pat::Ident(ident) => match ident.subpat {
-            Some((_, ref subpat)) => syn_error!(subpat, "unexpected subpattern"),
-            None => ident.ident.clone(),
-        },
-        Pat::Wild(wild) => Ident::new("_", wild.span()),
-        _ => syn_error!(pat, "expected ident"),
-    })
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub enum LuaType {
-    Any,
-    Nil,
-    Boolean,
-    Lightuserdata,
-    Number,
-    Integer,
-    String,
-    Table,
-    Function,
-    Userdata,
-    Thread,
-    Cdata,
-}
-
-impl fmt::Display for LuaType {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            LuaType::Any => write!(f, "any"),
-            LuaType::Nil => write!(f, "nil"),
-            LuaType::Boolean => write!(f, "boolean"),
-            LuaType::Lightuserdata => write!(f, "lightuserdata"),
-            LuaType::Number => write!(f, "number"),
-            LuaType::Integer => write!(f, "integer"),
-            LuaType::String => write!(f, "string"),
-            LuaType::Table => write!(f, "table"),
-            LuaType::Function => write!(f, "function"),
-            LuaType::Userdata => write!(f, "userdata"),
-            LuaType::Thread => write!(f, "thread"),
-            LuaType::Cdata => write!(f, "cdata"),
-        }
-    }
-}
-
-impl TryFrom<&Ident> for LuaType {
-    type Error = Error;
-
-    fn try_from(value: &Ident) -> Result<Self> {
-        Ok(match format!("{}", value.unraw()).as_str() {
-            "any" => Self::Any,
-            "nil" => Self::Nil,
-            "boolean" => Self::Boolean,
-            "lightuserdata" => Self::Lightuserdata,
-            "number" => Self::Number,
-            "integer" => Self::Integer,
-            "string" => Self::String,
-            "table" => Self::Table,
-            "function" => Self::Function,
-            "userdata" => Self::Userdata,
-            "thread" => Self::Thread,
-            "cdata" => Self::Cdata,
-            _ => syn_error!(value, "invalid lua type"),
-        })
-    }
-}
-
-impl TryFrom<&Type> for LuaType {
-    type Error = Error;
-
-    fn try_from(value: &Type) -> Result<Self> {
-        match value {
-            Type::Infer(_) => Ok(Self::Any),
-            Type::Path(path) if path.qself.is_none() => path.path.require_ident()?.try_into(),
-            _ => syn_error!(value, "invalid lua type"),
-        }
-    }
-}

crates/luaify/tests/test.rs

@@ -1,4 +1,5 @@
-use luaify::luaify;
+use luaify::{luaify, luaify_chunk};
+use pretty_assertions::assert_eq;
 
 #[test]
 fn raw_ident() {
@@ -76,13 +77,6 @@ fn local_fn() {
         }),
         r#"function(a,b)local function inner(c,d)end;return inner;end"#
     );
-    assert_eq!(
-        luaify!(|| {
-            fn check(self: string, arg: number) {}
-            inner
-        }),
-        r#"function()local function check(self,arg)do if type(self)=="number"then self=tostring(self);else assert(type(self)=="string","string expected in \'self\', got "..type(self));end;end;do local __arg=arg;arg=tonumber(arg);assert(arg~=nil,"number expected in \'arg\', got "..type(__arg));end;end;return inner;end"#
-    );
 }
 
 #[test]
@@ -207,37 +201,6 @@ fn loops() {
     );
 }
 
-#[test]
-fn type_checks() {
-    assert_eq!(luaify!(|s| {}), r#"function(s)end"#);
-    assert_eq!(
-        luaify!(|s: table| {}),
-        r#"function(s)do assert(type(s)=="table","table expected in \'s\', got "..type(s));end;end"#
-    );
-    assert_eq!(
-        luaify!(|s| { s as string }),
-        r#"function(s)do if type(s)=="number"then s=tostring(s);else assert(type(s)=="string","string expected in \'s\', got "..type(s));end;end;end"#
-    );
-    assert_eq!(
-        luaify!(|s| { s as number }),
-        r#"function(s)do local __s=s;s=tonumber(s);assert(s~=nil,"number expected in \'s\', got "..type(__s));end;end"#
-    );
-    assert_eq!(
-        luaify!(|s| { s as nil }),
-        r#"function(s)do assert(s==nil,"nil expected in \'s\', got "..type(s));end;end"#
-    );
-    assert_eq!(luaify!(|s| { s as any }), r#"function(s)do end;end"#);
-
-    assert_eq!(
-        luaify!(|s| {
-            let (ok, res) = coroutine::r#yield(thread);
-            ok as boolean;
-            res as nil;
-        }),
-        r#"function(s)local ok,res=coroutine.yield(thread);do assert(type(ok)=="boolean","boolean expected in \'ok\', got "..type(ok));end;do assert(res==nil,"nil expected in \'res\', got "..type(res));end;end"#
-    );
-}
-
 #[test]
 fn concat() {
     assert_eq!(luaify!(concat!(a)), r#"a"#);
@@ -402,3 +365,19 @@ fn length() {
         r#"local a,b,c=#a,#b,#c;"#
     );
 }
+
+#[test]
+fn chunk() {
+    assert_eq!(
+        luaify_chunk!({
+            if a == b {
+                c()
+            } else if b == c {
+                a()
+            } else {
+                d()
+            }
+        }),
+        "if a==b then c();elseif b==c then a();else d();end;"
+    );
+}

crates/luajit-sys/Cargo.toml

@@ -1,7 +1,11 @@
 [package]
 name = "luajit-sys"
-version = "0.1.0"
-edition = "2024"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
 
 [lib]
 path = "lib.rs"

crates/luajit-sys/lib.rs

@@ -1,3 +1,18 @@
+//! Raw bindings for LuaJIT generated using [bindgen](https://docs.rs/bindgen/).
+//!
+//! ## Feature flags
+//!
+//! Features flags are used to control certain features of LuaJIT. They are not enabled by default
+//! unless otherwise specified below.
+//!
+//! - `runtime`: links the target with `libluajit`. This should only be enabled by binary targets.
+//! - `jit`: enables the JIT compiler. *This is enabled by default.*
+//! - `ffi`: enables the FFI library. *This is enabled by default.*
+//! - `unwind`: configures LuaJIT to use stack unwinding instead of `longjmp` for error handling.
+//!   **This MUST be enabled if `panic = "unwind"` is set.**
+//! - `bundled-alloc`: configures LuaJIT to include its own bundled allocator. If this is not
+//!   enabled, LuaJIT will use the system allocator by default.
+//! - `lua52`: enables Lua 5.2 compatibility mode. *This is enabled by default.*
 #![allow(nonstandard_style)]
 use std::{ffi::*, ptr};
 

crates/luajit/Cargo.toml

@@ -1,7 +1,11 @@
 [package]
 name = "luajit"
-version = "0.1.0"
-edition = "2024"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+homepage.workspace = true
+repository.workspace = true
 
 [features]
 runtime = ["luajit-sys/runtime"]
@@ -10,6 +14,5 @@ unwind = ["luajit-sys/unwind"]
 [dependencies]
 bitflags = { version = "2.9.1", features = ["std"] }
 bstr = "1.12.0"
-luaffi = { version = "0.1.0", path = "../luaffi" }
-luajit-sys = { version = "0.1.0", path = "../luajit-sys" }
-thiserror = "2.0.12"
+luaffi = { path = "../luaffi" }
+luajit-sys = { path = "../luajit-sys" }

src/lib.rs

@@ -1,2 +1,27 @@
+//! luby standard library.
+#[cfg(feature = "fs")]
 pub use lb::fs;
+#[cfg(feature = "net")]
 pub use lb::net;
+#[cfg(feature = "task")]
+pub use lb::task;
+#[cfg(feature = "time")]
+pub use lb::time;
+
+#[cfg(feature = "sqlite")]
+pub use lb_sqlite::sqlite;
+
+#[doc(hidden)]
+pub fn open(#[allow(unused)] rt: &mut lb::runtime::Builder) {
+    #[cfg(feature = "task")]
+    rt.module::<task::lb_tasklib>();
+    #[cfg(feature = "time")]
+    rt.module::<time::lb_timelib>();
+    #[cfg(feature = "fs")]
+    rt.module::<fs::lb_fslib>();
+    #[cfg(feature = "net")]
+    rt.module::<net::lb_netlib>();
+
+    #[cfg(feature = "sqlite")]
+    rt.module::<sqlite::lb_sqlitelib>();
+}

src/main.rs

@@ -1,7 +1,8 @@
 use clap::Parser;
+use luajit::Chunk;
 use mimalloc::MiMalloc;
 use owo_colors::OwoColorize;
-use std::{backtrace::Backtrace, fmt::Display, net::SocketAddr, num::NonZero, panic, thread};
+use std::{backtrace::Backtrace, fmt::Display, num::NonZero, panic, process, thread};
 use sysexits::ExitCode;
 
 #[global_allocator]
@@ -20,21 +21,42 @@ fn panic_cb(panic: &panic::PanicHookInfo) {
     };
 
     eprint!(
-        "{}:\n{trace}",
+        "{}\n{trace}",
         format_args!(
             "thread '{}' panicked at {location}: {msg}",
             thread::current().name().unwrap_or("<unnamed>")
         )
         .red()
+        .bold()
     );
 
     eprintln!(
         "{}",
-        "This is a bug in luby. Please kindly report this at https://git.lua.re/luaneko/luby."
-            .yellow()
+        format_args!(
+            "luby should never panic. Please kindly report this bug at {}.",
+            env!("CARGO_PKG_REPOSITORY")
+        )
+        .yellow()
+        .bold()
     );
 }
 
+fn error_cb(err: &luajit::Error) {
+    match err.trace() {
+        Some(trace) => eprintln!("{}\n{trace}", err.red().bold()),
+        None => eprintln!("{}", err.red().bold()),
+    }
+
+    process::exit(1);
+}
+
+fn unwrap_exit<T, E: Display>(code: ExitCode) -> impl FnOnce(E) -> T {
+    move |err| {
+        eprintln!("{}", err.red().bold());
+        code.exit()
+    }
+}
+
 #[derive(Debug, Parser)]
 struct Args {
     /// Paths to scripts to execute.
@@ -45,7 +67,7 @@ struct Args {
     #[clap(long, short = 'e', value_name = "CHUNK")]
     eval: Vec<String>,
 
-    /// Libraries to require on startup.
+    /// Libraries to require.
     #[clap(long, short = 'l', value_name = "NAME")]
     lib: Vec<String>,
 
@@ -54,29 +76,65 @@ struct Args {
     log: tracing::Level,
 
     /// LuaJIT control commands.
-    #[clap(long, short = 'j', value_name = "CMD=FLAGS")]
+    #[clap(long, short = 'j', help_heading = "Runtime", value_name = "CMD=FLAGS")]
     jit: Vec<String>,
 
-    /// Number of tokio worker threads.
-    #[clap(long, value_name = "THREADS", default_value_t = Self::threads())]
+    /// Allow global variables.
+    #[clap(
+        long,
+        help_heading = "Runtime",
+        value_name = "ENABLED",
+        default_value_t = true
+    )]
+    allow_globals: bool,
+
+    /// Number of worker threads.
+    #[clap(
+        long,
+        short = 'T',
+        help_heading = "Runtime",
+        value_name = "COUNT",
+        default_value_t = Self::threads()
+    )]
     threads: NonZero<usize>,
 
-    /// Number of tokio blocking threads.
-    #[clap(long, value_name = "THREADS", default_value_t = Self::blocking_threads())]
+    /// Number of blocking threads.
+    #[clap(
+        long,
+        help_heading = "Runtime",
+        value_name = "COUNT",
+        default_value_t = Self::blocking_threads()
+    )]
     blocking_threads: NonZero<usize>,
 
     /// Enable tokio-console integration.
-    #[clap(long)]
+    #[cfg(feature = "tokio-console")]
+    #[clap(long, help_heading = "Debugging", value_name = "ENABLED")]
     enable_console: bool,
 
     /// tokio-console publish address.
+    #[cfg(feature = "tokio-console")]
     #[clap(
         long,
+        help_heading = "Debugging",
         value_name = "ADDRESS",
         default_value = "127.0.0.1:6669",
         requires = "enable_console"
     )]
-    console_addr: SocketAddr,
+    console_addr: std::net::SocketAddr,
+
+    /// Dump internal data.
+    #[clap(
+        long,
+        help_heading = "Debugging",
+        value_name = "DATA",
+        value_parser = ["cdef"]
+    )]
+    dump: Vec<String>,
+
+    /// Print version.
+    #[clap(long, short = 'V')]
+    version: bool,
 }
 
 impl Args {
@@ -89,17 +147,15 @@ impl Args {
     }
 }
 
-fn exit_err<T, E: Display>(code: ExitCode) -> impl FnOnce(E) -> T {
-    move |err| {
-        eprintln!("{}", err.red());
-        code.exit()
-    }
-}
-
-fn main() -> Result<(), ExitCode> {
+fn main() -> ExitCode {
     panic::set_hook(Box::new(panic_cb));
 
     let args = Args::parse();
+    if args.version {
+        print_version();
+        return ExitCode::Ok;
+    }
+
     init_logger(&args);
 
     let tokio = init_tokio(&args);
@@ -108,13 +164,28 @@ fn main() -> Result<(), ExitCode> {
 
     tokio.block_on(async {
         lua.await;
-        main.await.unwrap()
+        match main.await {
+            Ok(res) => res,
+            Err(err) => panic::resume_unwind(err.into_panic()),
+        }
     })
 }
 
+fn print_version() {
+    println!("luby {}", env!("VERGEN_GIT_DESCRIBE"));
+    println!("{}\n", env!("CARGO_PKG_HOMEPAGE"));
+    println!("Compiled with {} -- {}", luajit::version(), luajit::url());
+    println!(
+        "Compiled with rustc {} on {} for {}",
+        env!("VERGEN_RUSTC_SEMVER"),
+        env!("VERGEN_RUSTC_HOST_TRIPLE"),
+        env!("VERGEN_CARGO_TARGET_TRIPLE"),
+    );
+}
+
 fn init_logger(args: &Args) {
     use tracing::level_filters::LevelFilter;
-    use tracing_subscriber::{Layer, util::*};
+    use tracing_subscriber::util::*;
 
     let log = tracing_subscriber::fmt()
         .compact()
@@ -128,98 +199,68 @@ fn init_logger(args: &Args) {
         .with_target(false)
         .finish();
 
-    if args.enable_console {
+    #[cfg(feature = "tokio-console")]
+    {
+        use tracing_subscriber::Layer;
         console_subscriber::ConsoleLayer::builder()
             .with_default_env()
             .server_addr(args.console_addr)
             .spawn()
             .with_subscriber(log)
-            .init()
-    } else {
-        log.init()
+            .init();
     }
+
+    #[cfg(not(feature = "tokio-console"))]
+    log.init();
 }
 
 fn init_tokio(args: &Args) -> tokio::runtime::Runtime {
-    let mut rt = match args.threads.get() {
+    match args.threads.get() {
         1 => tokio::runtime::Builder::new_current_thread(),
         n => {
             let mut rt = tokio::runtime::Builder::new_multi_thread();
             rt.worker_threads(n - 1);
             rt
         }
-    };
-
-    rt.enable_all()
-        .thread_name("luby")
-        .max_blocking_threads(args.blocking_threads.get())
-        .build()
-        .unwrap_or_else(exit_err(ExitCode::OsErr))
+    }
+    .enable_all()
+    .thread_name("luby")
+    .max_blocking_threads(args.blocking_threads.get())
+    .build()
+    .unwrap_or_else(unwrap_exit(ExitCode::OsErr))
 }
 
 fn init_lua(args: &Args) -> lb::runtime::Runtime {
-    let rt = lb::runtime::Builder::new();
-    let mut rt = rt.build().unwrap_or_else(exit_err(ExitCode::Software));
+    let mut rt = lb::runtime::Builder::new();
+    luby::open(&mut rt);
 
-    for arg in args.jit.iter() {
-        let mut s = rt.guard();
-        if let Some((cmd, flags)) = parse_jitlib_cmd(arg)
-            && let Ok(_) = s.require(format!("jit.{cmd}"), 1)
-        {
-            (s.push("start"), s.get(-2), s.push(flags));
-            s.call(1, 0)
-        } else {
-            s.require("jit", 1).unwrap();
-            match arg.as_str() {
-                cmd @ ("on" | "off" | "flush") => {
-                    (s.push(cmd), s.get(-2));
-                    s.call(0, 0)
-                }
-                arg => {
-                    (s.push("opt"), s.get(-2));
-                    (s.push("start"), s.get(-2), s.push(arg));
-                    s.call(1, 0)
-                }
-            }
-        }
-        .unwrap_or_else(exit_err(ExitCode::Usage));
+    if args.dump.iter().find(|s| *s == "cdef").is_some() {
+        print!("{}", rt.registry()); // for cdef debugging
     }
 
-    rt
+    rt.unhandled_error(error_cb)
+        .prohibit_globals(!args.allow_globals)
+        .jit_opts(args.jit.iter())
+        .build()
+        .unwrap()
 }
 
-fn parse_jitlib_cmd(s: &str) -> Option<(&str, &str)> {
-    match s {
-        "p" => Some(("p", "Flspv10")),
-        "v" => Some(("v", "-")),
-        "dump" => Some(("dump", "tirs")),
-        _ => s.split_once('='),
-    }
-}
-
-async fn main_async(args: Args, state: &mut luajit::State) -> Result<(), ExitCode> {
+async fn main_async(args: Args, cx: &mut lb::runtime::Context) -> ExitCode {
     for ref path in args.path {
-        let mut s = state.guard();
         let chunk = match std::fs::read(path) {
             Ok(chunk) => chunk,
             Err(err) => {
-                eprintln!("{}", format_args!("{path}: {err}").red());
-                ExitCode::NoInput.exit();
+                eprintln!("{}", format_args!("{path}: {err}").red().bold());
+                return ExitCode::NoInput;
             }
         };
 
-        s.load(&luajit::Chunk::new(chunk).path(path))
-            .unwrap_or_else(exit_err(ExitCode::NoInput));
-
-        if let Err(err) = s.call_async(0, 0).await {
-            match err.trace() {
-                Some(trace) => eprintln!("{}\n{trace}", err.red()), // runtime error
-                None => eprintln!("{}", err.red()),
-            }
-
-            ExitCode::DataErr.exit();
+        if let Err(ref err) = cx.load(&Chunk::new(chunk).with_path(path)) {
+            cx.report_error(err);
+        } else if let Err(ref err) = cx.call_async(0, Some(0)).await {
+            cx.report_error(err);
         }
     }
 
-    Ok(())
+    ExitCode::Ok
 }

test.lua

@@ -1,6 +0,0 @@
-local ffi = require("ffi")
-local lb = ffi.new("struct lb_core")
-
-print(lb)
-
-lb.spawn("")

tests/main.lua

@@ -0,0 +1,188 @@
+if (...) ~= nil and (...).type == "group" then return end -- prevent recursive harness call
+
+local ok = pcall(require, "lb:task")
+if not ok then error("lua test harness requires 'lb:task'") end
+local ok, time = pcall(require, "lb:time")
+if not ok then error("lua test harness requires 'lb:time'") end
+local ok, fs = pcall(require, "lb:fs")
+if not ok then error("lua test harness requires 'lb:fs'") end
+
+local global = _G
+local color = {
+  reset = "\x1b[0m",
+  pass = "\x1b[32;1m", -- green
+  fail = "\x1b[31;1m", -- red
+  faint = "\x1b[2;39;49m", -- faint
+}
+
+local icon = {
+  check = "\u{2713}",
+  cross = "\u{00d7}",
+  chevron = "\u{203a}",
+}
+
+local function style(name, s)
+  return ("%s%s%s"):format(color[name], s, color.reset)
+end
+
+local function rjust(s, w)
+  if w == nil then w = 12 end
+  if #s >= w then return s end
+  return (" "):rep(w - #s) .. s
+end
+
+local function create_test(name, f, group)
+  local test = { type = "test", name = name or "", group = group, state = "pending", f = f }
+  local fenv = setmetatable({}, { __index = global, __newindex = global })
+  setfenv(f, fenv)
+  return test
+end
+
+local function create_group(name, f, parent)
+  local group = { type = "group", name = name or "", parent = parent, items = {} }
+  local fenv = setmetatable({
+    describe = function(name, f)
+      local item = create_group(name, f, group)
+      table.insert(group.items, item)
+      return item
+    end,
+
+    test = function(name, f)
+      local item = create_test(name, f, group)
+      table.insert(group.items, item)
+      return item
+    end,
+  }, { __index = global, __newindex = global })
+
+  setfenv(f, fenv)
+  f(group)
+  return group
+end
+
+local function name_test(test)
+  local name = test.name
+  local group = test.group
+  while group ~= nil do
+    if group.name ~= "" then name = ("%s %s %s"):format(group.name, icon.chevron, name) end
+    group = group.parent
+  end
+  return name
+end
+
+local function trace(msg)
+  return style("fail", msg) .. debug.traceback("", 2):sub(("\nstack traceback:"):len() + 1)
+end
+
+local function run_test(test)
+  local ok, trace = xpcall(test.f, trace, test)
+  if ok then
+    test.state = "pass"
+    print(("%s %s"):format(style("pass", rjust("PASS")), name_test(test)))
+  else
+    test.state = "fail"
+    print(("%s %s\n\n%s\n"):format(style("fail", rjust("!!! FAIL")), name_test(test), trace))
+  end
+  collectgarbage() -- gc after each test to test destructors
+  return test
+end
+
+local function start(cx, item)
+  if item.type == "test" then
+    table.insert(cx.tasks, spawn(run_test, item))
+  elseif item.type == "group" then
+    for _, item in ipairs(item.items) do
+      start(cx, item)
+    end
+  end
+end
+
+local function check_refs()
+  -- ensure all refs were properly unref'ed
+  local registry = debug.getregistry()
+  local count = #registry
+  local ref = 0 -- FREELIST_REF
+  while type(registry[ref]) == "number" do
+    local next = registry[ref]
+    registry[ref], ref = nil, next
+  end
+  for i = 1, count do
+    local value = registry[i]
+    if type(value) ~= "thread" then -- ignore threads pinned by the runtime
+      assert(rawequal(registry[i], nil), ("ref %d not unref'ed: %s"):format(i, registry[i]))
+    end
+  end
+end
+
+local function main(item)
+  local cx = { tasks = {} }
+  local time, pass, fail = time.instant(), 0, 0
+  start(cx, item)
+  for _, task in ipairs(cx.tasks) do
+    if task:await().state == "pass" then
+      pass = pass + 1
+    else
+      fail = fail + 1
+    end
+  end
+  local elapsed = time:elapsed_secs()
+  local retcode
+  if fail == 0 then
+    print(style("pass", ("\t%s %d tests passed"):format(icon.check, pass)))
+    retcode = 0
+  else
+    print(
+      ("\t%s, %s"):format(
+        style("pass", ("%s %d tests passed"):format(icon.check, pass)),
+        style("fail", ("%s %d tests failed"):format(icon.cross, fail))
+      )
+    )
+    retcode = 1
+  end
+  print(style("faint", ("\t%s completed in %.2fs"):format(icon.chevron, elapsed)))
+  cx = nil
+  collectgarbage()
+  check_refs() -- check that all refs were properly unref'ed in destructors
+  return retcode -- report error to cargo
+end
+
+return main(create_group("", function()
+  local function include(path, pat)
+    for entry in fs.glob_dir(path, pat) do
+      local path = entry:path()
+      local f, err = loadfile(path)
+      if not f then error(err) end
+      describe(path, f)
+    end
+  end
+
+  local function include_doctest(path, pat)
+    for entry in fs.glob_dir(path, pat) do
+      local line, doctest = 0, nil
+      for s in fs.read(entry:path()):gmatch("([^\n]*)\n?") do
+        line = line + 1
+        local prefix = s:match("^%s*///")
+        s = prefix and s:sub(#prefix + 1)
+        if s and not s:match("^%s*```%s*$") then
+          if s:match("^%s*```lua$") then
+            doctest = { line = line, col = #prefix + 2 }
+          elseif doctest then
+            table.insert(doctest, (" "):rep(#prefix) .. s)
+          end
+        else
+          if doctest then
+            local name = ("%s:%d:%d"):format(entry:path(), doctest.line, doctest.col)
+            local f, err = loadstring(table.concat(doctest, "\n"), "@" .. name)
+            if not f then error(err) end
+            test(("%s %s"):format(name, style("faint", "(doctest)")), f)
+          end
+          doctest = nil
+        end
+      end
+    end
+  end
+
+  include("tests", "**/*.lua")
+  include("crates", "*/tests/**/*.lua")
+  include_doctest("src", "**/*.rs")
+  include_doctest("crates", "*/src/**/*.rs")
+end))

tests/main.rs

@@ -0,0 +1,50 @@
+use luajit::Chunk;
+use owo_colors::OwoColorize;
+use std::{
+    fs, panic,
+    process::{self, ExitCode},
+};
+
+fn main() -> ExitCode {
+    let tokio = tokio::runtime::Runtime::new().unwrap();
+    let lua = {
+        let mut rt = lb::runtime::Builder::new();
+        luby::open(&mut rt);
+        rt.unhandled_error(error_cb)
+            .prohibit_globals(true)
+            .build()
+            .unwrap()
+    };
+
+    let path = "tests/main.lua";
+    let main = lua.spawn(async move |s| {
+        if let Err(ref err) = s.load(&Chunk::new(fs::read(path).unwrap()).with_path(path)) {
+            s.report_error(err);
+        } else if let Err(ref err) = s.call_async(0, Some(1)).await {
+            s.report_error(err);
+        }
+
+        if s.slot(1).integer().unwrap_or(1) == 0 {
+            ExitCode::SUCCESS
+        } else {
+            ExitCode::FAILURE
+        }
+    });
+
+    tokio.block_on(async move {
+        lua.await;
+        match main.await {
+            Ok(res) => res,
+            Err(err) => panic::resume_unwind(err.into_panic()),
+        }
+    })
+}
+
+fn error_cb(err: &luajit::Error) {
+    match err.trace() {
+        Some(trace) => eprintln!("{}\n{trace}", err.red().bold()),
+        None => eprintln!("{}", err.red().bold()),
+    }
+
+    process::exit(1);
+}