feat: support arrow function in on_chunks_loaded callback (#12193)

* feat: support arrow function in on_chunks_loaded callback

* test: add case

Author: chenjiahan

crates/rspack_plugin_javascript/src/plugin/mod.rs

@@ -243,6 +243,11 @@ impl JsPlugin {
     let mut header: Vec<Cow<str>> = Vec::new();
     let mut startup: Vec<Cow<str>> = Vec::new();
     let mut allow_inline_startup = true;
+    let supports_arrow_function = compilation
+      .options
+      .output
+      .environment
+      .supports_arrow_function();
 
     if allow_inline_startup && module_factories {
       startup.push("// module factories are used so entry inlining is disabled".into());
@@ -419,17 +424,25 @@ impl JsPlugin {
           }
 
           if !chunk_ids.is_empty() {
+            let on_chunks_loaded_callback = if supports_arrow_function {
+              format!("() => {}({module_id_expr})", RuntimeGlobals::REQUIRE)
+            } else {
+              format!(
+                "function() {{ return {}({module_id_expr}) }}",
+                RuntimeGlobals::REQUIRE
+              )
+            };
             buf2.push(
               format!(
-                "{}{}(undefined, {}, function() {{ return {}({module_id_expr}) }});",
+                "{}{}(undefined, {}, {});",
                 if i + 1 == entries.len() {
                   format!("var {} = ", RuntimeGlobals::EXPORTS)
                 } else {
                   "".to_string()
                 },
                 RuntimeGlobals::ON_CHUNKS_LOADED,
                 stringify_array(&chunk_ids),
-                RuntimeGlobals::REQUIRE
+                on_chunks_loaded_callback
               )
               .into(),
             );

tests/rspack-test/hotCases/chunks/split-chunks-arrow-function/__snapshots__/web/0.snap.txt

@@ -0,0 +1,13 @@
+# Case split-chunks-arrow-function: Step 0
+
+## Changed Files
+
+
+## Asset Files
+- Bundle: 0.js
+- Bundle: [runtime of 1].js
+
+## Manifest
+
+
+## Update

tests/rspack-test/hotCases/chunks/split-chunks-arrow-function/__snapshots__/web/1.snap.txt

@@ -0,0 +1,70 @@
+# Case split-chunks-arrow-function: Step 1
+
+## Changed Files
+- node_modules/vendor.js
+
+## Asset Files
+- Bundle: 0.js
+- Bundle: [runtime of 1].js
+- Manifest: [runtime of 1].LAST_HASH.hot-update.json, size: 29
+- Update: 0.LAST_HASH.hot-update.js, size: 227
+- Update: 1.LAST_HASH.hot-update.js, size: 179
+
+## Manifest
+
+### [runtime of 1].LAST_HASH.hot-update.json
+
+```json
+{"c":["0","1"],"r":[],"m":[]}
+```
+
+
+## Update
+
+
+### 0.LAST_HASH.hot-update.js
+
+#### Changed Modules
+- ./node_modules/vendor.js
+
+#### Changed Runtime Modules
+
+
+#### Changed Content
+```js
+self["webpackHotUpdate"]("0", {
+"./node_modules/vendor.js": 
+/*!********************************!*\
+  !*** ./node_modules/vendor.js ***!
+  \********************************/
+(function (module) {
+module.exports = "2";
+
+
+}),
+
+});
+```
+
+
+
+### 1.LAST_HASH.hot-update.js
+
+#### Changed Modules
+
+
+#### Changed Runtime Modules
+- webpack/runtime/get_full_hash
+
+#### Changed Content
+```js
+"use strict";
+self["webpackHotUpdate"]("1", {},function(__webpack_require__) {
+// webpack/runtime/get_full_hash
+(() => {
+__webpack_require__.h = () => ("CURRENT_HASH")
+})();
+
+}
+);
+```

tests/rspack-test/hotCases/chunks/split-chunks-arrow-function/index.js

@@ -0,0 +1,9 @@
+import vendor from "vendor";
+
+it("should hot update a splitted initial chunk with `environment.arrowFunction: true`", async () => {
+	expect(vendor).toBe("1");
+	await NEXT_HMR();
+	expect(vendor).toBe("2");
+});
+
+module.hot.accept(["vendor"]);

tests/rspack-test/hotCases/chunks/split-chunks-arrow-function/node_modules/vendor.js

@@ -0,0 +1,15 @@
+module.exports = {
+	output: {
+		filename: "[name].js",
+		environment: {
+			arrowFunction: true
+		}
+	},
+	optimization: {
+		chunkIds: "total-size",
+		splitChunks: {
+			chunks: "all",
+			minSize: 0
+		}
+	}
+};

tests/rspack-test/hotCases/chunks/split-chunks-arrow-function/rspack.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+  findBundle: function (i, options) {
+    return ["main.js", "0.js"];
+  }
+};