fix: css runtime should have hmr handler when lazy-compilation

crates/rspack_core/src/compiler/compilation.rs

@@ -1408,13 +1408,18 @@ impl Compilation {
       let mut runtime_requirements;
 
       loop {
+        // runtime_requirements: rt_requirements of last time
+        // runtime_requirements_mut: changed rt_requirements
+        // requirements: all rt_requirements
         runtime_requirements = runtime_requirements_mut;
         runtime_requirements_mut = RuntimeGlobals::default();
         call_hook(
           requirements,
           &runtime_requirements,
           &mut runtime_requirements_mut,
         )?;
+
+        // check if we have changes to runtime_requirements
         runtime_requirements_mut =
           runtime_requirements_mut.difference(requirements.intersection(runtime_requirements_mut));
         if runtime_requirements_mut.is_empty() {
@@ -1891,6 +1896,7 @@ impl Compilation {
     let runtime_module_identifier =
       ModuleIdentifier::from(format!("{}/{}", &chunk.runtime, module.identifier()));
     module.attach(*chunk_ukey);
+
     self.chunk_graph.add_module(runtime_module_identifier);
     self
       .chunk_graph

crates/rspack_plugin_extract_css/src/plugin.rs

@@ -432,35 +432,29 @@ async fn compilation(
 }
 
 #[plugin_hook(CompilationRuntimeRequirementInTree for PluginCssExtract)]
-fn runtime_requirements_in_tree(
+fn runtime_requirement_in_tree(
   &self,
   compilation: &mut Compilation,
   chunk_ukey: &ChunkUkey,
   _all_runtime_requirements: &RuntimeGlobals,
   runtime_requirements: &RuntimeGlobals,
   runtime_requirements_mut: &mut RuntimeGlobals,
 ) -> Result<Option<()>> {
+  // different from webpack, Rspack can invoke this multiple times,
+  // each time with current runtime_globals, and records every mutation
+  // by `runtime_requirements_mut`, but this RuntimeModule depends on
+  // 2 runtimeGlobals, if check current runtime_requirements, we might
+  // insert CssLoadingRuntimeModule with with_loading: true but with_hmr: false
+  // for the first time, and with_loading: false but with_hmr: true for the
+  // second time
+  // For plugin that depends on 2 runtime_globals, should check all_runtime_requirements
   if !self.options.runtime {
     return Ok(None);
   }
 
-  let with_loading = runtime_requirements.contains(RuntimeGlobals::ENSURE_CHUNK_HANDLERS) && {
-    let chunk = compilation.chunk_by_ukey.expect_get(chunk_ukey);
-
-    chunk
-      .get_all_async_chunks(&compilation.chunk_group_by_ukey)
-      .iter()
-      .any(|chunk| {
-        !compilation
-          .chunk_graph
-          .get_chunk_modules_by_source_type(chunk, SOURCE_TYPE[0], &compilation.get_module_graph())
-          .is_empty()
-      })
-  };
-
-  let with_hmr = runtime_requirements.contains(RuntimeGlobals::HMR_DOWNLOAD_UPDATE_HANDLERS);
-
-  if with_loading || with_hmr {
+  if runtime_requirements.contains(RuntimeGlobals::HMR_DOWNLOAD_UPDATE_HANDLERS)
+    || runtime_requirements.contains(RuntimeGlobals::ENSURE_CHUNK_HANDLERS)
+  {
     if let Some(chunk_filename) = self.options.chunk_filename.template()
       && chunk_filename.contains("hash")
     {
@@ -499,8 +493,6 @@ fn runtime_requirements_in_tree(
         self.options.attributes.clone(),
         self.options.link_type.clone(),
         self.options.insert.clone(),
-        with_loading,
-        with_hmr,
       )),
     )?;
   }
@@ -668,7 +660,7 @@ impl Plugin for PluginCssExtract {
       .context
       .compilation_hooks
       .runtime_requirement_in_tree
-      .tap(runtime_requirements_in_tree::new(self));
+      .tap(runtime_requirement_in_tree::new(self));
     ctx
       .context
       .compilation_hooks

crates/rspack_plugin_extract_css/src/runtime.rs

@@ -3,10 +3,12 @@ use std::sync::Arc;
 use cow_utils::CowUtils;
 use rspack_collections::UkeySet;
 use rspack_core::{
-  impl_runtime_module, rspack_sources::RawSource, ChunkUkey, Compilation, CrossOriginLoading,
-  RuntimeGlobals, RuntimeModule, RuntimeModuleStage,
+  impl_runtime_module,
+  rspack_sources::{RawSource, SourceExt},
+  ChunkUkey, Compilation, CrossOriginLoading, RuntimeGlobals, RuntimeModule, RuntimeModuleStage,
 };
 use rspack_error::Result;
+use rspack_plugin_runtime::get_chunk_runtime_requirements;
 use rustc_hash::FxHashMap;
 
 use crate::plugin::{InsertType, SOURCE_TYPE};
@@ -22,9 +24,6 @@ pub(crate) struct CssLoadingRuntimeModule {
   attributes: FxHashMap<String, String>,
   link_type: Option<String>,
   insert: InsertType,
-
-  loading: bool,
-  hmr: bool,
 }
 
 impl CssLoadingRuntimeModule {
@@ -33,10 +32,8 @@ impl CssLoadingRuntimeModule {
     attributes: FxHashMap<String, String>,
     link_type: Option<String>,
     insert: InsertType,
-    loading: bool,
-    hmr: bool,
   ) -> Self {
-    Self::with_default(chunk, attributes, link_type, insert, loading, hmr)
+    Self::with_default(chunk, attributes, link_type, insert)
   }
 
   fn get_css_chunks(&self, compilation: &Compilation) -> UkeySet<ChunkUkey> {
@@ -73,9 +70,34 @@ impl RuntimeModule for CssLoadingRuntimeModule {
     compilation: &rspack_core::Compilation,
   ) -> Result<rspack_core::rspack_sources::BoxSource> {
     let runtime = RUNTIME_CODE;
+    let runtime_requirements = get_chunk_runtime_requirements(compilation, &self.chunk);
+
+    let with_loading = runtime_requirements.contains(RuntimeGlobals::ENSURE_CHUNK_HANDLERS) && {
+      let chunk = compilation.chunk_by_ukey.expect_get(&self.chunk);
+
+      chunk
+        .get_all_async_chunks(&compilation.chunk_group_by_ukey)
+        .iter()
+        .any(|chunk| {
+          !compilation
+            .chunk_graph
+            .get_chunk_modules_by_source_type(
+              chunk,
+              SOURCE_TYPE[0],
+              &compilation.get_module_graph(),
+            )
+            .is_empty()
+        })
+    };
+
+    let with_hmr = runtime_requirements.contains(RuntimeGlobals::HMR_DOWNLOAD_UPDATE_HANDLERS);
+
+    if !with_hmr && !with_loading {
+      return Ok(RawSource::from("").boxed());
+    }
 
     let mut attr = String::default();
-    let mut attributes = self.attributes.iter().collect::<Vec<_>>();
+    let mut attributes: Vec<(&String, &String)> = self.attributes.iter().collect::<Vec<_>>();
     attributes.sort_unstable_by(|(k1, _), (k2, _)| k1.cmp(k2));
 
     for (attr_key, attr_value) in attributes {
@@ -121,7 +143,7 @@ impl RuntimeModule for CssLoadingRuntimeModule {
       ),
     };
 
-    let runtime = if self.loading {
+    let runtime = if with_loading {
       let chunks = self.get_css_chunks(compilation);
       if chunks.is_empty() {
         runtime.cow_replace("__WITH_LOADING__", "// no chunk loading")
@@ -171,7 +193,7 @@ impl RuntimeModule for CssLoadingRuntimeModule {
       runtime.cow_replace("__WITH_LOADING__", "// no chunk loading")
     };
 
-    let runtime = if self.hmr {
+    let runtime = if with_hmr {
       runtime.cow_replace(
         "__WITH_HMT__",
         &WITH_HMR.cow_replace(

packages/playground/cases/lazy-compilation/css-update/index.test.ts

@@ -0,0 +1,21 @@
+import { expect, test } from "@/fixtures";
+
+test("should update style", async ({ page }) => {
+	const body = await page.$("body");
+	const backgroundColor = await body!.evaluate(
+		el => window.getComputedStyle(el).backgroundColor
+	);
+	// first time enter the page, style is red
+	expect(backgroundColor, "red");
+
+	// second time enter the page, this time brings query,
+	// trigger lazy-compile
+	const url = await body!.evaluate(() => window.location.href);
+	await page.goto(`${url}?1`);
+	const updatedBody = await page.$("body");
+	const updatedBackgroundColor = await updatedBody!.evaluate(
+		el => window.getComputedStyle(el).backgroundColor
+	);
+	// first time enter the page, style is red
+	expect(updatedBackgroundColor, "blue");
+});

packages/playground/cases/lazy-compilation/css-update/rspack.config.js

@@ -0,0 +1,37 @@
+const rspack = require("@rspack/core");
+
+/** @type { import('@rspack/core').RspackOptions } */
+module.exports = {
+	context: __dirname,
+	entry: "./src/index.js",
+	mode: "development",
+	module: {
+		rules: [
+			{
+				test: /\.css$/,
+				use: [rspack.CssExtractRspackPlugin.loader, "css-loader"]
+			}
+		]
+	},
+	plugins: [new rspack.HtmlRspackPlugin(), new rspack.CssExtractRspackPlugin()],
+	experiments: {
+		css: false,
+		lazyCompilation: true
+	},
+	optimization: {
+		splitChunks: {
+			minSize: 0,
+			chunks: "all",
+			cacheGroups: {
+				styles: {
+					test: /\.css$/,
+					name: "style.css"
+				}
+			}
+		}
+	},
+	devServer: {
+		hot: true,
+		port: 5678
+	}
+};

packages/playground/cases/lazy-compilation/css-update/src/blue.css

@@ -0,0 +1,3 @@
+body {
+	background-color: blue;
+}

packages/playground/cases/lazy-compilation/css-update/src/change.js

@@ -0,0 +1 @@
+import "./blue.css";

packages/playground/cases/lazy-compilation/css-update/src/index.js

@@ -0,0 +1,6 @@
+import "./red.css";
+
+if (new URL(window.location.href).search) {
+	// @ts-expect-error change.js no dts
+	import("./change.js");
+}

packages/playground/cases/lazy-compilation/css-update/src/red.css

@@ -0,0 +1,3 @@
+body {
+	background-color: red;
+}

tests/plugin-test/css-extract/cases/runtime/expected/runtime~main.js

@@ -93,6 +93,17 @@ __webpack_require__.e = function (chunkId) {
           return "" + chunkId + ".js";
         };
 
+})();
+// webpack/runtime/get mini-css chunk filename
+(() => {
+// This function allow to reference chunks
+        __webpack_require__.miniCssF = function (chunkId) {
+          // return url for filenames not based on template
+
+          // return url for filenames based on template
+          return "" + chunkId + ".css";
+        };
+
 })();
 // webpack/runtime/global
 (() => {