Implement task sleep function

crates/lb/Cargo.toml

@@ -8,7 +8,7 @@ homepage.workspace = true
 repository.workspace = true
 
 [features]
-task = []
+task = ["tokio/time"]
 fs = ["tokio/fs"]
 net = ["tokio/net"]
 

crates/lb/src/task.lua

@@ -1,6 +1,10 @@
+-- include task functions in the global scope
 local task = require("lb:task")
 
--- include `lb_tasklib::spawn` in the global scope
+function sleep(ms)
+  return task:sleep(ms)
+end
+
 function spawn(f, ...)
   return task:spawn(f, ...)
 end

crates/lb/src/task.rs

@@ -14,7 +14,11 @@ impl lb_tasklib {
         Self
     }
 
-    pub extern "Lua" fn spawn(self, f: function, ...) {
+    pub async extern "Lua-C" fn sleep(&self, ms: f64) {
+        sleep(Duration::from_secs_f64(ms / 1000.)).await;
+    }
+
+    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!())))
     }