fix: panic in add_entry_batch when loader calls importModule

crates/rspack_core/src/compilation/build_module_graph/module_executor/mod.rs

@@ -63,6 +63,10 @@ impl Default for ModuleExecutor {
 }
 
 impl ModuleExecutor {
+  pub fn is_running(&self) -> bool {
+    self.event_sender.is_some()
+  }
+
   pub async fn before_build_module_graph(&mut self, compilation: &Compilation) -> Result<()> {
     let mut make_artifact = self.make_artifact.steal();
     let mut exports_info_artifact = self.exports_info_artifact.steal();

crates/rspack_core/src/compilation/mod.rs

@@ -652,9 +652,20 @@ impl Compilation {
       self.add_entry(entry, options).await?;
     }
 
+    // ensure module executor is running so loaders can call `importModule`
+    let started_executor = match &self.module_executor {
+      Some(me) if !me.is_running() => {
+        let mut module_executor = self.module_executor.take().expect("checked above");
+        module_executor.before_build_module_graph(self).await?;
+        self.module_executor = Some(module_executor);
+        true
+      }
+      _ => false,
+    };
+
     let make_artifact = self.build_module_graph_artifact.steal();
     let exports_info_artifact = self.exports_info_artifact.steal();
-    let (make_artifact, exports_info_artifact) = update_module_graph(
+    let build_result = update_module_graph(
       self,
       make_artifact,
       exports_info_artifact,
@@ -668,11 +679,29 @@ impl Compilation {
           .collect(),
       )],
     )
-    .await?;
-    self.build_module_graph_artifact = make_artifact.into();
-    self.exports_info_artifact = exports_info_artifact.into();
+    .await;
+
+    // restore artifacts before teardown — after_build_module_graph reads them
+    let build_result = match build_result {
+      Ok((make_artifact, exports_info_artifact)) => {
+        self.build_module_graph_artifact = make_artifact.into();
+        self.exports_info_artifact = exports_info_artifact.into();
+        Ok(())
+      }
+      Err(e) => {
+        self.build_module_graph_artifact = StealCell::new(BuildModuleGraphArtifact::new());
+        self.exports_info_artifact = StealCell::new(ExportsInfoArtifact::default());
+        Err(e)
+      }
+    };
 
-    Ok(())
+    // tear down the executor so build_module_graph_pass can set it up fresh
+    if started_executor && let Some(mut module_executor) = self.module_executor.take() {
+      module_executor.after_build_module_graph(self).await?;
+      self.module_executor = Some(module_executor);
+    }
+
+    build_result
   }
 
   pub async fn add_include(&mut self, args: Vec<(BoxDependency, EntryOptions)>) -> Result<()> {

tests/rspack-test/configCases/compilation/add-entry-import-module/data.js

@@ -0,0 +1 @@
+export default "hello from imported module";

tests/rspack-test/configCases/compilation/add-entry-import-module/entry.js

@@ -0,0 +1,2 @@
+import data from "./data.js";
+export default data;

tests/rspack-test/configCases/compilation/add-entry-import-module/index.js

@@ -0,0 +1,3 @@
+it("should have built the dynamically added entry", () => {
+	expect(__STATS__.compilation.namedChunks).toHaveProperty("dynamic");
+});

tests/rspack-test/configCases/compilation/add-entry-import-module/loader.js

@@ -0,0 +1,7 @@
+/** @type {import("@rspack/core").PitchLoaderDefinitionFunction} */
+exports.pitch = async function (remaining) {
+	const result = await this.importModule(
+		this.resourcePath + ".webpack[javascript/auto]" + "!=!" + remaining
+	);
+	return result.default || result;
+};

tests/rspack-test/configCases/compilation/add-entry-import-module/rspack.config.js

@@ -0,0 +1,45 @@
+const path = require("path");
+
+const PLUGIN_NAME = "AddEntryWithImportModulePlugin";
+
+class AddEntryWithImportModulePlugin {
+	/**
+	 * @param {import("@rspack/core").Compiler} compiler
+	 */
+	apply(compiler) {
+		const { EntryPlugin } = compiler.rspack;
+
+		compiler.hooks.make.tapPromise(PLUGIN_NAME, compilation => {
+			return new Promise((resolve, reject) => {
+				compilation.addEntry(
+					compiler.context,
+					EntryPlugin.createDependency(
+						path.resolve(__dirname, "entry.js")
+					),
+					{ name: "dynamic" },
+					(err) => {
+						if (err) reject(err);
+						else resolve();
+					}
+				);
+			});
+		});
+	}
+}
+
+/**@type {import("@rspack/core").Configuration}*/
+module.exports = {
+	output: {
+		filename: "[name].js"
+	},
+	module: {
+		rules: [
+			{
+				test: /entry\.js$/,
+				use: [{ loader: "./loader", options: {} }],
+				type: "asset/source"
+			}
+		]
+	},
+	plugins: [new AddEntryWithImportModulePlugin()]
+};