Update library heuristics as short term solution for missing metadata. (#1293)

* Update library heuristics as short term solution for missing metadata.

- Return first `org-dartlang` library as `vmservice.rootLib`
  (or `main` if not found)
- Manually add dart_sdk module metadata in `MetadataProvider`.
- Update and add tests.

Helps: dart-lang/sdk#44760
Helps: #1226

* Test fix

* Addressed CR comments

Author: Anna Gringauze

dwds/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 10.0.2-dev
+
+- Fix missing sdk libraries in `getObject()` calls.
+- Fix incorrect `rootLib` returned by `ChromeProxyService`.
+
 ## 10.0.1
 
 - Support `webkit_inspection_protocol` version `^1.0.0`.

dwds/lib/src/debugging/classes.dart

@@ -66,8 +66,14 @@ class ClassHelper extends Domain {
       throw UnsupportedError('unknown library: $libraryId');
     }
     var libraryRef = await inspector.libraryHelper.libraryRefFor(libraryId);
+    if (libraryRef == null) {
+      throw Exception('Could not find library: $libraryId');
+    }
     var classRef = classRefFor(libraryId, splitId.last);
     clazz = await _constructClass(libraryRef, classRef);
+    if (clazz == null) {
+      throw Exception('Could not contruct class: $classRef');
+    }
     return _classes[objectId] = clazz;
   }
 

dwds/lib/src/debugging/inspector.dart

@@ -4,6 +4,7 @@
 
 // @dart = 2.9
 
+import 'package:logging/logging.dart';
 import 'package:path/path.dart' as p;
 import 'package:vm_service/vm_service.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
@@ -33,6 +34,8 @@ class AppInspector extends Domain {
 
   Future<List<ScriptRef>> get scriptRefs => _cachedScriptRefs ??= _getScripts();
 
+  final _logger = Logger('AppInspector');
+
   /// Map of scriptRef ID to [ScriptRef].
   final _scriptRefsById = <String, ScriptRef>{};
 
@@ -80,18 +83,11 @@ class AppInspector extends Domain {
 
   Future<void> _initialize() async {
     var libraries = await libraryHelper.libraryRefs;
-    isolate.libraries.addAll(libraries);
+    isolate.rootLib = await libraryHelper.rootLib;
 
+    isolate.libraries.addAll(libraries);
     await DartUri.recordAbsoluteUris(libraries.map((lib) => lib.uri));
 
-    // This relies on the convention that the 2nd to last library is the root
-    // library (and the last one is the bootstrap library).
-    if (libraries.length >= 2) {
-      isolate.rootLib = libraries[libraries.length - 2];
-    } else {
-      isolate.rootLib = libraries.last;
-    }
-
     isolate.extensionRPCs.addAll(await _getExtensionRpcs());
   }
 
@@ -328,15 +324,28 @@ function($argsString) {
 
   Future<Obj> getObject(String isolateId, String objectId,
       {int offset, int count}) async {
-    var library = await _getLibrary(isolateId, objectId);
-    if (library != null) return library;
-    var clazz = await classHelper.forObjectId(objectId);
-    if (clazz != null) return clazz;
-    var scriptRef = _scriptRefsById[objectId];
-    if (scriptRef != null) return await _getScript(isolateId, scriptRef);
-    var instance = await instanceHelper.instanceFor(remoteObjectFor(objectId),
-        offset: offset, count: count);
-    if (instance != null) return instance;
+    try {
+      var library = await _getLibrary(isolateId, objectId);
+      if (library != null) {
+        return library;
+      }
+      var clazz = await classHelper.forObjectId(objectId);
+      if (clazz != null) {
+        return clazz;
+      }
+      var scriptRef = _scriptRefsById[objectId];
+      if (scriptRef != null) {
+        return await _getScript(isolateId, scriptRef);
+      }
+      var instance = await instanceHelper.instanceFor(remoteObjectFor(objectId),
+          offset: offset, count: count);
+      if (instance != null) {
+        return instance;
+      }
+    } catch (e, s) {
+      _logger.log(Level.FINE, 'getObject failed with exception: $e:$s');
+      rethrow;
+    }
     throw UnsupportedError('Only libraries, instances, classes, and scripts '
         'are supported for getObject');
   }

dwds/lib/src/debugging/libraries.dart

@@ -20,8 +20,22 @@ class LibraryHelper extends Domain {
   /// Map of libraryRef ID to [LibraryRef].
   final _libraryRefsById = <String, LibraryRef>{};
 
+  LibraryRef _rootLib;
+
   LibraryHelper(AppInspector Function() provider) : super(provider);
 
+  Future<LibraryRef> get rootLib async {
+    if (_rootLib != null) return _rootLib;
+    // TODO: read entrypoint from app metadata.
+    // Issue: https://github.com/dart-lang/webdev/issues/1290
+    var libraries = await libraryRefs;
+    _rootLib = libraries.firstWhere((lib) => lib.name.contains('org-dartlang'));
+    _rootLib =
+        _rootLib ?? libraries.firstWhere((lib) => lib.name.contains('main'));
+    _rootLib = _rootLib ?? (libraries.isNotEmpty ? libraries.last : null);
+    return _rootLib;
+  }
+
   /// Returns all libraryRefs in the app.
   ///
   /// Note this can return a cached result.

dwds/lib/src/debugging/metadata/provider.dart

@@ -27,6 +27,45 @@ class MetadataProvider {
   final Map<String, List<String>> _scripts = {};
   final _metadataMemoizer = AsyncMemoizer();
 
+  /// Implicitly imported libraries in any DDC component.
+  ///
+  /// Currently dart_sdk module does not come with the metadata.
+  /// To allow evaluation of expressions that use libraries and
+  /// types from the SDK (such as a dart Type object), add the
+  /// metadata for dart_sdk manually.
+  ///
+  /// TODO: Generate sdk module metadata to be consumed by debugger.
+  /// Issue: https://github.com/dart-lang/sdk/issues/45477
+  List<String> get sdkLibraries => const [
+        'dart:_runtime',
+        'dart:_debugger',
+        'dart:_foreign_helper',
+        'dart:_interceptors',
+        'dart:_internal',
+        'dart:_isolate_helper',
+        'dart:_js_helper',
+        'dart:_js_primitives',
+        'dart:_metadata',
+        'dart:_native_typed_data',
+        'dart:async',
+        'dart:collection',
+        'dart:convert',
+        'dart:developer',
+        'dart:io',
+        'dart:isolate',
+        'dart:js',
+        'dart:js_util',
+        'dart:math',
+        'dart:typed_data',
+        'dart:indexed_db',
+        'dart:html',
+        'dart:html_common',
+        'dart:svg',
+        'dart:web_audio',
+        'dart:web_gl',
+        'dart:web_sql'
+      ];
+
   MetadataProvider(this.entrypoint, this._assetReader)
       : _soundNullSafety = false;
 
@@ -150,6 +189,7 @@ class MetadataProvider {
             entrypoint.replaceAll('.bootstrap.js', '.ddc_merged_metadata');
         var merged = await _assetReader.metadataContents(serverPath);
         if (merged != null) {
+          _addSdkMetadata();
           for (var contents in merged.split('\n')) {
             try {
               if (contents == null ||
@@ -197,6 +237,16 @@ class MetadataProvider {
       }
     }
   }
+
+  void _addSdkMetadata() {
+    var moduleName = 'dart_sdk';
+
+    for (var lib in sdkLibraries) {
+      _libraries.add(lib);
+      _scripts[lib] = [];
+      _scriptToModule[lib] = moduleName;
+    }
+  }
 }
 
 class AbsoluteImportUriException implements Exception {

dwds/lib/src/debugging/modules.dart

@@ -75,7 +75,10 @@ class Modules {
 
     var scriptToModule = await provider.scriptToModule;
     for (var script in scriptToModule.keys) {
-      var serverPath = DartUri(script, _root).serverPath;
+      var serverPath = script.startsWith('dart:')
+          ? script
+          : DartUri(script, _root).serverPath;
+
       _sourceToModule[serverPath] = scriptToModule[script];
       _sourceToLibrary[serverPath] = Uri.parse(script);
       _libraryToModule[script] = scriptToModule[script];