Fixing sourcemaps for DDC Library Bundle builds (#4376)

Consult's the Dart Loader's `urlToModuleId` structure to account for 'nonstandard' paths (multiple main files, etc).

Author: Markzipan

build_web_compilers/CHANGELOG.md

@@ -1,3 +1,6 @@
+## 4.4.14
+- Update DDC Library Bundle to use path-resolvable module names for sourcemap IDs.
+
 ## 4.4.13
 - Update sourcemap paths for DDC Library Bundle sources.
 - Update bootstrapper for DDC Library Bundle apps to auto-run main.

build_web_compilers/lib/src/dev_compiler_bootstrap.dart

@@ -142,8 +142,7 @@ $librariesString
       // `packages/` for lib modules. We set baseUrl to `/` to simplify things,
       // and we only allow you to serve top level directories.
       final moduleName = ddcModuleName(jsId);
-      final libraryId = ddcLibraryId(jsId);
-      modulePaths[libraryId] =
+      modulePaths[moduleName] =
           jsId.path.startsWith('lib')
               ? '$moduleName$jsModuleExtension'
               : _context.relative(
@@ -785,13 +784,19 @@ $_simpleLoaderScript
         !window.\$dartStackTraceUtility.ready) {
       window.\$dartStackTraceUtility.ready = true;
       window.\$dartStackTraceUtility.setSourceMapProvider(function(url) {
-        var baseUrl = window.location.protocol + '//' + window.location.host;
-        url = url.replace(baseUrl + '/', '');
-        if (url == 'dart_sdk.js') {
+        // Try to resolve the library ID using the loader's internal map.
+        if (window.\$dartLoader && window.\$dartLoader.urlToModuleId) {
+          var id = window.\$dartLoader.urlToModuleId.get(url);
+          if (id) {
+             return dartDevEmbedder.debugger.getSourceMap(id);
+          }
+        }
+        if (url.endsWith('dart_sdk.js')) {
           return dartDevEmbedder.debugger.getSourceMap('dart_sdk');
         }
-        url = url.replace(".lib.js", "");
-        return dartDevEmbedder.debugger.getSourceMap(url);
+        url = url.replace("$jsModuleExtension", "");
+        let relativeUrl = url.replace(_currentDirectory, "");
+        return dartDevEmbedder.debugger.getSourceMap(relativeUrl);
       });
     }
 

build_web_compilers/pubspec.yaml

@@ -1,5 +1,5 @@
 name: build_web_compilers
-version: 4.4.13
+version: 4.4.14
 description: Builder implementations wrapping the dart2js and DDC compilers.
 repository: https://github.com/dart-lang/build/tree/master/build_web_compilers
 resolution: workspace

build_web_compilers/test/ddc_library_bundle_bootstrap_test.dart

@@ -21,14 +21,11 @@ void main() {
   initializePlatforms();
 
   final startingBuilders = {
-    // Uses the real sdk copy builder to copy required files from the SDK.
-    sdkJsCopyRequirejs(const BuilderOptions({})),
-    sdkJsCompile(defaultBuilderOptions),
     const ModuleLibraryBuilder(),
     MetaModuleBuilder(ddcPlatform),
     MetaModuleCleanBuilder(ddcPlatform),
     ModuleBuilder(ddcPlatform),
-    ddcKernelBuilder(const BuilderOptions({})),
+    ddcKernelBuilder(const BuilderOptions({'ddc-library-bundle': true})),
     DevCompilerBuilder(
       platform: ddcPlatform,
       ddcLibraryBundle: ddcLibraryBundle,
@@ -50,6 +47,11 @@ void main() {
         'b|lib/b.dart': '''final world = 'world';''',
         // Add a fake asset so that the build_web_compilers package exists.
         'build_web_compilers|fake.txt': '',
+        'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': '',
+        'build_web_compilers|lib/src/dev_compiler/require.js': '',
+        'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js': '',
+        'build_web_compilers|lib/src/dev_compiler_stack_trace/stack_trace_mapper.dart.js':
+            '',
       };
       final startingExpectedOutputs = <String, Object>{
         'a|lib/.ddc.meta_module.clean': isNotNull,
@@ -76,11 +78,6 @@ void main() {
         'b|lib/b.module.library': isNotNull,
         'build_web_compilers|lib/.ddc.meta_module.clean': isNotNull,
         'build_web_compilers|lib/.ddc.meta_module.raw': isNotNull,
-        'build_web_compilers|lib/src/dev_compiler/dart_sdk.js.map': isNotNull,
-        'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': isNotNull,
-        'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js':
-            isNotNull,
-        'build_web_compilers|lib/src/dev_compiler/require.js': isNotNull,
       };
 
       test('base build', () async {
@@ -115,16 +112,10 @@ void main() {
               // Contains a script pointer to main's bootstrap.js file.
               contains('"src": "index.dart.bootstrap.js", "id": "data-main"'),
               // Maps non-lib modules to remove the top level dir.
-              contains(
-                '"src": "index.ddc.js", "id": "org-dartlang-app:///web/index.dart"',
-              ),
+              contains('"src": "index.ddc.js", "id": "web/index"'),
               // Maps lib modules to packages path
-              contains(
-                '"src": "packages/a/a.ddc.js", "id": "package:a/a.dart"',
-              ),
-              contains(
-                '"src": "packages/b/b.ddc.js", "id": "package:b/b.dart"',
-              ),
+              contains('"src": "packages/a/a.ddc.js", "id": "packages/a/a"'),
+              contains('"src": "packages/b/b.ddc.js", "id": "packages/b/b"'),
               // Imports the dart sdk.
               contains('"id": "dart_sdk"'),
               isNot(contains('lib/a')),
@@ -157,6 +148,11 @@ void main() {
       ''',
           // Add a fake asset so that the build_web_compilers package exists.
           'build_web_compilers|fake.txt': '',
+          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': '',
+          'build_web_compilers|lib/src/dev_compiler/require.js': '',
+          'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js': '',
+          'build_web_compilers|lib/src/dev_compiler_stack_trace/stack_trace_mapper.dart.js':
+              '',
         };
         // Check that we are invoking the correct
         final expectedOutputs = {
@@ -174,9 +170,7 @@ void main() {
           'a|web/b.dart.js': decodedMatches(
             allOf([
               // Confirm that `a.dart` is the actual primary source.
-              contains(
-                '"src": "a.ddc.js", "id": "org-dartlang-app:///web/a.dart"',
-              ),
+              contains('"src": "a.ddc.js", "id": "web/a"'),
               // And `b.dart` is the application whose 'main' is being invoked.
               contains('"src": "b.dart.bootstrap.js", "id": "data-main'),
             ]),
@@ -186,11 +180,6 @@ void main() {
           'a|web/b.module.library': isNotNull,
           'build_web_compilers|lib/.ddc.meta_module.clean': isNotNull,
           'build_web_compilers|lib/.ddc.meta_module.raw': isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js.map': isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js':
-              isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/require.js': isNotNull,
         };
 
         await testBuilders(
@@ -206,6 +195,11 @@ void main() {
           'a|lib/app.dart': 'void main() {}',
           // Add a fake asset so that the build_web_compilers package exists.
           'build_web_compilers|fake.txt': '',
+          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': '',
+          'build_web_compilers|lib/src/dev_compiler/require.js': '',
+          'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js': '',
+          'build_web_compilers|lib/src/dev_compiler_stack_trace/stack_trace_mapper.dart.js':
+              '',
         };
         final expectedOutputs = {
           'a|lib/.ddc.meta_module.clean': isNotNull,
@@ -216,9 +210,7 @@ void main() {
           'a|lib/app.dart.js': decodedMatches(
             // Confirm that the child name is referenced via a package: uri
             // and not relative path to the root dir being served.
-            contains(
-              '"src": "packages/a/app.ddc.js", "id": "package:a/app.dart"',
-            ),
+            contains('"src": "packages/a/app.ddc.js", "id": "packages/a/app"'),
           ),
           'a|lib/app.ddc.dill': isNotNull,
           'a|lib/app.ddc.js.map': isNotNull,
@@ -229,11 +221,6 @@ void main() {
           'a|lib/app.module.library': isNotNull,
           'build_web_compilers|lib/.ddc.meta_module.clean': isNotNull,
           'build_web_compilers|lib/.ddc.meta_module.raw': isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js.map': isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js':
-              isNotNull,
-          'build_web_compilers|lib/src/dev_compiler/require.js': isNotNull,
         };
 
         await testBuilders(
@@ -279,5 +266,125 @@ void main() {
             'longer locked behind the --canary flag',
       );
     });
+    group('module system', () {
+      test('resolves paths correctly in nested entrypoints', () async {
+        // Test that an entrypoint compiled at web/sub_dir/main.dart is served
+        // relative to the entrypoint directory (e.g., web/sub_dir/main.ddc.js
+        // and not web/sub_dir/sub_dir/main.ddc.js)
+        final builderOptions = const BuilderOptions({
+          'compiler': 'dartdevc',
+          'ddc-library-bundle': true,
+          'native_null_assertions': false,
+        });
+        final builder = WebEntrypointBuilder.fromOptions(builderOptions);
+        final assets = {
+          'a|web/sub/main.dart': 'void main() {}',
+          'build_web_compilers|fake.txt': '',
+          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': '',
+          'build_web_compilers|lib/src/dev_compiler/require.js': '',
+          'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js': '',
+          'build_web_compilers|lib/src/dev_compiler_stack_trace/stack_trace_mapper.dart.js':
+              '',
+        };
+
+        final ddcLibraryBundleBuilders = {
+          const ModuleLibraryBuilder(),
+          MetaModuleBuilder(ddcPlatform),
+          MetaModuleCleanBuilder(ddcPlatform),
+          ModuleBuilder(ddcPlatform),
+          ddcKernelBuilder(const BuilderOptions({'ddc-library-bundle': true})),
+          DevCompilerBuilder(platform: ddcPlatform, ddcLibraryBundle: true),
+        };
+
+        final expectedOutputs = {
+          'a|web/sub/main.dart.js': decodedMatches(
+            allOf([
+              contains('"src": "main.ddc.js"'),
+              isNot(contains('"src": "sub/main.ddc.js"')),
+            ]),
+          ),
+          'build_web_compilers|lib/.ddc.meta_module.raw': isNotNull,
+          'build_web_compilers|lib/.ddc.meta_module.clean': isNotNull,
+          'a|web/sub/main.module.library': isNotNull,
+          'a|lib/.ddc.meta_module.raw': isNotNull,
+          'a|lib/.ddc.meta_module.clean': isNotNull,
+          'a|web/sub/main.ddc.module': isNotNull,
+          'a|web/sub/main.ddc.dill': isNotNull,
+          'a|web/sub/main.ddc.js': isNotNull,
+          'a|web/sub/main.ddc.js.map': isNotNull,
+          'a|web/sub/main.ddc.js.metadata': isNotNull,
+          'a|web/sub/main.dart.bootstrap.js': isNotNull,
+          'a|web/sub/main.dart.bootstrap.end.js': isNotNull,
+          'a|web/sub/main.digests': isNotNull,
+          'a|web/sub/main.dart.ddc_merged_metadata': isNotNull,
+        };
+
+        await testBuilders(
+          [...ddcLibraryBundleBuilders, builder],
+          assets,
+          outputs: expectedOutputs,
+        );
+      });
+
+      test('properly outputs script names during bootstrap', () async {
+        final builderOptions = const BuilderOptions({
+          'compiler': 'dartdevc',
+          'ddc-library-bundle': true,
+          'native_null_assertions': false,
+        });
+        final builder = WebEntrypointBuilder.fromOptions(builderOptions);
+        final assets = {
+          'a|web/main.dart': 'void main() {}',
+          'build_web_compilers|fake.txt': '',
+          'build_web_compilers|lib/src/dev_compiler/dart_sdk.js': '',
+          'build_web_compilers|lib/src/dev_compiler/require.js': '',
+          'build_web_compilers|lib/src/dev_compiler/ddc_module_loader.js': '',
+          'build_web_compilers|lib/src/dev_compiler_stack_trace/stack_trace_mapper.dart.js':
+              '',
+        };
+
+        final ddcLibraryBundleBuilders = {
+          const ModuleLibraryBuilder(),
+          MetaModuleBuilder(ddcPlatform),
+          MetaModuleCleanBuilder(ddcPlatform),
+          ModuleBuilder(ddcPlatform),
+          ddcKernelBuilder(const BuilderOptions({'ddc-library-bundle': true})),
+          DevCompilerBuilder(platform: ddcPlatform, ddcLibraryBundle: true),
+        };
+
+        await testBuilders(
+          [...ddcLibraryBundleBuilders, builder],
+          assets,
+          outputs: {
+            'a|web/main.dart.js': decodedMatches(
+              allOf([
+                contains('"id": "web/main"'),
+                isNot(contains('"id": "org-dartlang-app:///web/main.dart"')),
+                contains('"src": "main.ddc.js"'),
+              ]),
+            ),
+            'a|web/main.ddc.js.map': decodedMatches(
+              allOf([
+                contains('"file":"main.ddc.js"'),
+                contains('"sources":["main.dart"]'),
+              ]),
+            ),
+            'build_web_compilers|lib/.ddc.meta_module.raw': isNotNull,
+            'build_web_compilers|lib/.ddc.meta_module.clean': isNotNull,
+            'a|web/main.module.library': isNotNull,
+            'a|lib/.ddc.meta_module.raw': isNotNull,
+            'a|lib/.ddc.meta_module.clean': isNotNull,
+            'a|web/main.ddc.module': isNotNull,
+            'a|web/main.ddc.dill': isNotNull,
+            'a|web/main.ddc.js': isNotNull,
+            'a|web/main.ddc.js.metadata': isNotNull,
+            'a|web/main.dart.bootstrap.js': isNotNull,
+            'a|web/main.dart.bootstrap.end.js': isNotNull,
+            'a|web/main.digests': isNotNull,
+            'a|web/main.dart.ddc_merged_metadata': isNotNull,
+          },
+        );
+      });
+    });
   });
 }