refactor: diff context module lazy once mode (#6398)

crates/rspack_core/src/context_module.rs

@@ -22,14 +22,15 @@ use rustc_hash::FxHashMap as HashMap;
 use rustc_hash::FxHashSet as HashSet;
 
 use crate::{
-  contextify, get_exports_type_with_strict, impl_module_meta_info, returning_function,
-  stringify_map, to_path, AsyncDependenciesBlock, AsyncDependenciesBlockIdentifier, BoxDependency,
-  BuildContext, BuildInfo, BuildMeta, BuildMetaDefaultObject, BuildMetaExportsType, BuildResult,
-  ChunkGraph, ChunkGroupOptions, CodeGenerationResult, Compilation, ConcatenationScope,
-  ContextElementDependency, DependenciesBlock, Dependency, DependencyCategory, DependencyId,
-  DynamicImportMode, ExportsType, FactoryMeta, FakeNamespaceObjectMode, GroupOptions,
-  LibIdentOptions, Module, ModuleType, Resolve, ResolveInnerOptions,
-  ResolveOptionsWithDependencyType, ResolverFactory, RuntimeGlobals, RuntimeSpec, SourceType,
+  block_promise, contextify, get_exports_type_with_strict, impl_module_meta_info,
+  returning_function, stringify_map, to_path, AsyncDependenciesBlock,
+  AsyncDependenciesBlockIdentifier, BoxDependency, BuildContext, BuildInfo, BuildMeta,
+  BuildMetaDefaultObject, BuildMetaExportsType, BuildResult, ChunkGraph, ChunkGroupOptions,
+  CodeGenerationResult, Compilation, ConcatenationScope, ContextElementDependency,
+  DependenciesBlock, Dependency, DependencyCategory, DependencyId, DynamicImportMode, ExportsType,
+  FactoryMeta, FakeNamespaceObjectMode, GroupOptions, LibIdentOptions, Module, ModuleType, Resolve,
+  ResolveInnerOptions, ResolveOptionsWithDependencyType, ResolverFactory, RuntimeGlobals,
+  RuntimeSpec, SourceType,
 };
 
 #[derive(Debug, Clone)]
@@ -277,7 +278,7 @@ impl ContextModule {
   fn get_fake_map_init_statement(&self, fake_map: &FakeMapValue) -> String {
     match fake_map {
       FakeMapValue::Bit(_) => "".to_string(),
-      FakeMapValue::Map(map) => json_stringify(map),
+      FakeMapValue::Map(map) => format!("var fakeMap = {}", json_stringify(map)),
     }
   }
 
@@ -377,7 +378,11 @@ impl ContextModule {
   }
 
   #[inline]
-  fn get_source_string(&self, compilation: &Compilation) -> BoxSource {
+  fn get_source_string(
+    &self,
+    compilation: &Compilation,
+    code_gen_result: &mut CodeGenerationResult,
+  ) -> BoxSource {
     match self.options.context_options.mode {
       ContextMode::Lazy => {
         if !self.get_blocks().is_empty() {
@@ -387,13 +392,11 @@ impl ContextModule {
         }
       }
       ContextMode::LazyOnce => {
-        let module_graph = compilation.get_module_graph();
-        let block = self
-          .get_blocks()
-          .first()
-          .expect("LazyOnce ContextModule should have first block");
-        let block = module_graph.block_by_id(block).expect("should have block");
-        self.generate_source(block.get_dependencies(), compilation)
+        if let Some(block) = self.get_blocks().first() {
+          self.get_lazy_once_source(compilation, block, code_gen_result)
+        } else {
+          self.get_source_for_empty_async_context(compilation)
+        }
       }
       ContextMode::Sync => {
         if !self.get_dependencies().is_empty() {
@@ -560,6 +563,67 @@ impl ContextModule {
     source.boxed()
   }
 
+  fn get_lazy_once_source(
+    &self,
+    compilation: &Compilation,
+    block_id: &AsyncDependenciesBlockIdentifier,
+    code_gen_result: &mut CodeGenerationResult,
+  ) -> BoxSource {
+    let mg = compilation.get_module_graph();
+    let block = mg.block_by_id_expect(block_id);
+    let dependencies = block.get_dependencies();
+    let promise = block_promise(
+      Some(block_id),
+      &mut code_gen_result.runtime_requirements,
+      compilation,
+    );
+    let map = self.get_user_request_map(dependencies, compilation);
+    let fake_map = self.get_fake_map(dependencies, compilation);
+    let then_function = if !matches!(
+      fake_map,
+      FakeMapValue::Bit(FakeNamespaceObjectMode::NAMESPACE)
+    ) {
+      formatdoc! {r#"
+        function(id) {{
+          {}
+        }}
+        "#,
+        self.get_return_module_object_source(&fake_map, true, "fakeMap[id]"),
+      }
+    } else {
+      RuntimeGlobals::REQUIRE.name().to_string()
+    };
+    let source = formatdoc! {r#"
+      var map = {map};
+      {fake_map_init_statement}
+
+      function webpackAsyncContext(req) {{
+        return webpackAsyncContextResolve(req).then({then_function});
+      }}
+      function webpackAsyncContextResolve(req) {{
+        return {promise}.then(function() {{
+          if(!{has_own_property}(map, req)) {{
+            var e = new Error("Cannot find module '" + req + "'");
+            e.code = 'MODULE_NOT_FOUND';
+            throw e;
+          }}
+          return map[req];
+        }})
+      }}
+      webpackAsyncContext.keys = {keys};
+      webpackAsyncContext.resolve = webpackAsyncContextResolve;
+      webpackAsyncContext.id = {id};
+      module.exports = webpackAsyncContext;
+      "#,
+      map = json_stringify(&map),
+      fake_map_init_statement = self.get_fake_map_init_statement(&fake_map),
+      has_own_property = RuntimeGlobals::HAS_OWN_PROPERTY,
+      keys = returning_function("Object.keys(map)", ""),
+      id = json_stringify(self.id(&compilation.chunk_graph))
+    };
+    RawSource::from(source).boxed()
+  }
+
   fn get_sync_source(&self, compilation: &Compilation) -> BoxSource {
     let dependencies = self.get_dependencies();
     let map = self.get_user_request_map(dependencies, compilation);
@@ -799,7 +863,7 @@ impl Module for ContextModule {
     _: Option<ConcatenationScope>,
   ) -> Result<CodeGenerationResult> {
     let mut code_generation_result = CodeGenerationResult::default();
-    let source = self.get_source_string(compilation);
+    let source = self.get_source_string(compilation, &mut code_generation_result);
     code_generation_result.add(SourceType::JavaScript, source);
     let mut all_deps = self.get_dependencies().to_vec();
     let module_graph = compilation.get_module_graph();

crates/rspack_core/src/module_graph/mod.rs

@@ -646,6 +646,17 @@ impl<'a> ModuleGraph<'a> {
     self.loop_partials(|p| p.blocks.get(block_id))?.as_ref()
   }
 
+  pub fn block_by_id_expect(
+    &self,
+    block_id: &AsyncDependenciesBlockIdentifier,
+  ) -> &AsyncDependenciesBlock {
+    self
+      .loop_partials(|p| p.blocks.get(block_id))
+      .expect("should insert block before get it")
+      .as_ref()
+      .expect("block has been removed to None")
+  }
+
   pub fn dependencies(&self) -> HashMap<DependencyId, &BoxDependency> {
     let mut res = HashMap::default();
     for item in self.partials.iter() {

crates/rspack_core/src/options/module.rs

@@ -74,7 +74,7 @@ impl From<&str> for DynamicImportMode {
       "weak" => DynamicImportMode::Weak,
       "eager" => DynamicImportMode::Eager,
       "lazy" => DynamicImportMode::Lazy,
-      "lazyOnce" => DynamicImportMode::LazyOnce,
+      "lazy-once" => DynamicImportMode::LazyOnce,
       _ => {
         // TODO: warning
         DynamicImportMode::default()

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/index.js

@@ -1,2 +1,3 @@
 import "./dynamic-import";
 import "./cjs-require";
+import "./namespace-object-lazy"

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/cjs-esmodule.js

@@ -0,0 +1,3 @@
+exports.__esModule = true;
+exports.default = "default";
+exports.named = "named";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/cjs.js

@@ -0,0 +1,2 @@
+exports.default = "default";
+exports.named = "named";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-cjs/null.js

@@ -0,0 +1 @@
+module.exports = null;

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-cjs/one.js

@@ -0,0 +1,2 @@
+exports.named = "named";
+exports.default = "default";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-cjs/three.js

@@ -0,0 +1,2 @@
+exports.named = "named";
+exports.default = "default";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-cjs/two.js

@@ -0,0 +1,4 @@
+exports.__esModule = true;
+exports.named = "named";
+exports.default = "default";
+

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-harmony/one.js

@@ -0,0 +1,2 @@
+export default "default";
+export var named = "named";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-harmony/three.js

@@ -0,0 +1,2 @@
+export default "default";
+export var named = "named";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-harmony/two.js

@@ -0,0 +1,2 @@
+export default "default";
+export var named = "named";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-mixed/json.json

@@ -0,0 +1,4 @@
+{
+    "default": "default",
+    "named": "named"
+}

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-mixed/null.js

@@ -0,0 +1 @@
+module.exports = null;

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-mixed/one.js

@@ -0,0 +1,2 @@
+exports.named = "named";
+exports.default = "default";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-mixed/three.js

@@ -0,0 +1,2 @@
+export default "default";
+export var named = "named";

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/dir-mixed/two.js

@@ -0,0 +1,4 @@
+exports.__esModule = true;
+exports.named = "named";
+exports.default = "default";
+

packages/rspack-test-tools/tests/runtimeDiffCases/module-context-module/src/namespace-object-lazy/index.js

@@ -0,0 +1,88 @@
+// non-mjs-namespace-object-lazy
+
+it("should receive a namespace object when importing commonjs", function(done) {
+	import("./cjs").then(function(result) {
+		expect(result).toEqual(nsObj({ named: "named", default: { named: "named", default: "default" } }));
+		done();
+	}).catch(done);
+});
+
+it("should receive a namespace object when importing commonjs with __esModule", function(done) {
+	import("./cjs-esmodule").then(function(result) {
+		expect(result).toEqual({ __esModule: true, named: "named", default: "default" });
+		done();
+	}).catch(done);
+});
+
+function contextCJS(name) {
+	return Promise.all([
+		import(`./dir-cjs/${name}`),
+		import(/* webpackMode: "lazy-once", webpackChunkName: "dir-cjs-1" */`./dir-cjs?1/${name}`),
+		// import(/* webpackMode: "eager" */`./dir-cjs?2/${name}`)
+	]).then(function(results) {
+		// return import(/* webpackMode: "weak" */`./dir-cjs/${name}`).then(function(r) {
+		// 	results.push(r);
+		// 	return results;
+		// });
+	});
+}
+
+function contextHarmony(name) {
+	return Promise.all([
+		import(`./dir-harmony/${name}`),
+		import(/* webpackMode: "lazy-once", webpackChunkName: "dir-harmony-1" */`./dir-harmony?1/${name}`),
+		// import(/* webpackMode: "eager" */`./dir-harmony?2/${name}`)
+	]).then(function(results) {
+		// return import(/* webpackMode: "weak" */`./dir-harmony/${name}`).then(function(r) {
+		// 	results.push(r);
+		// 	return results;
+		// });
+	});
+}
+
+function contextMixed(name) {
+	return Promise.all([
+		import(`./dir-mixed/${name}`),
+		import(/* webpackMode: "lazy-once", webpackChunkName: "dir-mixed-1" */`./dir-mixed?1/${name}`),
+		// import(/* webpackMode: "eager" */`./dir-mixed?2/${name}`)
+	]).then(function(results) {
+		// return import(/* webpackMode: "weak" */`./dir-mixed/${name}`).then(function(r) {
+		// 	results.push(r);
+		// 	return results;
+		// });
+	});
+}
+
+function promiseTest(promise, equalsTo) {
+	return promise.then(function(results) {
+		for(const result of results)
+			expect(result).toEqual(equalsTo);
+	});
+}
+
+it("should receive a namespace object when importing commonjs via context", function() {
+	return Promise.all([
+		promiseTest(contextCJS("one"), nsObj({ named: "named", default: { named: "named", default: "default" } })),
+		promiseTest(contextCJS("two"), { __esModule: true, named: "named", default: "default" }),
+		promiseTest(contextCJS("three"), nsObj({ named: "named", default: { named: "named", default: "default" } })),
+		promiseTest(contextCJS("null"), nsObj({ default: null }))
+	]);
+});
+
+it("should receive a namespace object when importing harmony via context", function() {
+	return Promise.all([
+		promiseTest(contextHarmony("one"), nsObj({ named: "named", default: "default" })),
+		promiseTest(contextHarmony("two"), nsObj({ named: "named", default: "default" })),
+		promiseTest(contextHarmony("three"), nsObj({ named: "named", default: "default" }))
+	]);
+});
+
+it("should receive a namespace object when importing mixed content via context", function() {
+	return Promise.all([
+		promiseTest(contextMixed("one"), nsObj({ named: "named", default: { named: "named", default: "default" } })),
+		promiseTest(contextMixed("two"), { __esModule: true, named: "named", default: "default" }),
+		promiseTest(contextMixed("three"), nsObj({ named: "named", default: "default" })),
+		promiseTest(contextMixed("null"), nsObj({ default: null })),
+		promiseTest(contextMixed("json.json"), nsObj({ named: "named", default: { named: "named", default: "default" } }))
+	]);
+});