Switch to "proxyrequire" function (follow up Luau 0.671)

Author: khvzak

src/luau/mod.rs

@@ -1,4 +1,5 @@
 use std::ffi::CStr;
+use std::mem;
 use std::os::raw::c_int;
 
 use crate::error::Result;
@@ -12,18 +13,27 @@ pub use require::{NavigateError, Require};
 impl Lua {
     /// Create a custom Luau `require` function using provided [`Require`] implementation to find
     /// and load modules.
-    ///
-    /// The provided object is stored in the Lua registry and will not be garbage collected
-    /// until the Lua state is closed.
     #[cfg(any(feature = "luau", doc))]
     #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
     pub fn create_require_function<R: Require + 'static>(&self, require: R) -> Result<Function> {
+        unsafe extern "C-unwind" fn mlua_require(state: *mut ffi::lua_State) -> c_int {
+            let mut ar: ffi::lua_Debug = mem::zeroed();
+            if ffi::lua_getinfo(state, 1, cstr!("s"), &mut ar) == 0 {
+                ffi::luaL_error(state, cstr!("require is not supported in this context"));
+            }
+            let top = ffi::lua_gettop(state);
+            ffi::lua_pushvalue(state, ffi::lua_upvalueindex(2)); // the "proxy" require function
+            ffi::lua_pushvalue(state, 1); // require path
+            ffi::lua_pushstring(state, ar.source); // current file
+            ffi::lua_call(state, 2, ffi::LUA_MULTRET);
+            ffi::lua_gettop(state) - top
+        }
+
         unsafe {
             self.exec_raw((), move |state| {
                 let requirer_ptr = ffi::lua_newuserdata_t::<Box<dyn Require>>(state, Box::new(require));
-                // Keep the require object in the registry to prevent it from being garbage collected
-                ffi::lua_rawsetp(state, ffi::LUA_REGISTRYINDEX, requirer_ptr as *const _);
-                ffi::lua_pushrequire(state, require::init_config, requirer_ptr as *mut _);
+                ffi::luarequire_pushproxyrequire(state, require::init_config, requirer_ptr as *mut _);
+                ffi::lua_pushcclosured(state, mlua_require, cstr!("require"), 2);
             })
         }
     }

src/luau/require.rs

@@ -86,7 +86,8 @@ pub trait Require: MaybeSend {
     fn config(&self) -> IoResult<Vec<u8>>;
 
     /// Loads the module and returns the result (function or table).
-    fn load(&self, lua: &Lua, chunk_name: &str, content: &[u8]) -> Result<Value> {
+    fn load(&self, lua: &Lua, path: &str, chunk_name: &str, content: &[u8]) -> Result<Value> {
+        let _ = path;
         lua.load(content).set_name(chunk_name).call(())
     }
 }
@@ -413,15 +414,17 @@ pub(super) unsafe extern "C" fn init_config(config: *mut ffi::luarequire_Configu
     unsafe extern "C-unwind" fn load(
         state: *mut ffi::lua_State,
         ctx: *mut c_void,
+        path: *const c_char,
         chunk_name: *const c_char,
         contents: *const c_char,
     ) -> c_int {
         let this = &*(ctx as *const Box<dyn Require>);
+        let path = CStr::from_ptr(path).to_string_lossy();
         let chunk_name = CStr::from_ptr(chunk_name).to_string_lossy();
         let contents = CStr::from_ptr(contents).to_bytes();
         let lua = Lua::get_or_init_from_ptr(state);
         callback_error_ext(state, ptr::null_mut(), false, move |_extra, _| {
-            match this.load(lua, &chunk_name, contents)? {
+            match this.load(lua, &path, &chunk_name, contents)? {
                 Value::Nil => lua.lock().push(true)?,
                 value => lua.lock().push(value)?,
             };