Restructuring to start supporting breakpoints and sourcemaps (#377)

dwds/lib/src/chrome_proxy_service.dart

@@ -11,6 +11,7 @@ import 'package:pub_semver/pub_semver.dart' as semver;
 import 'package:vm_service_lib/vm_service_lib.dart';
 import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
 
+import 'debugger.dart';
 import 'helpers.dart';
 
 /// A proxy from the chrome debug protocol to the dart vm service protocol.
@@ -38,6 +39,9 @@ class ChromeProxyService implements VmServiceInterface {
   /// This may be null during a hot restart or page refresh.
   Isolate _isolate;
 
+  /// Provides debugger-related functionality.
+  Debugger debugger;
+
   /// Fields that are specific to the current [_isolate].
   ///
   /// These need to get cleared whenever [destroyIsolate] is called.
@@ -71,7 +75,6 @@ class ChromeProxyService implements VmServiceInterface {
           '$appInstanceId');
     }
     var tabConnection = await appTab.connect();
-    await tabConnection.debugger.enable();
     await tabConnection.runtime.enable();
 
     // TODO: What about `architectureBits`, `targetCPU`, `hostCPU` and `pid`?
@@ -81,10 +84,16 @@ class ChromeProxyService implements VmServiceInterface {
       ..startTime = DateTime.now().millisecondsSinceEpoch
       ..version = Platform.version;
     var service = ChromeProxyService._(vm, appTab, tabConnection, assetHandler);
+    await service._initialize();
     await service.createIsolate();
     return service;
   }
 
+  Future<Null> _initialize() async {
+    debugger = Debugger(this);
+    await debugger.initialize();
+  }
+
   /// Creates a new [_isolate].
   ///
   /// Only one isolate at a time is supported, but they should be cleaned up
@@ -133,12 +142,12 @@ class ChromeProxyService implements VmServiceInterface {
     _vm.isolates.add(isolateRef);
     _isolate = isolate;
 
-    _streamNotify(
+    streamNotify(
         'Isolate',
         Event()
           ..kind = EventKind.kIsolateStart
           ..isolate = isolateRef);
-    _streamNotify(
+    streamNotify(
         'Isolate',
         Event()
           ..kind = EventKind.kIsolateRunnable
@@ -148,7 +157,7 @@ class ChromeProxyService implements VmServiceInterface {
     // isolate, but devtools doesn't recognize extensions after a page refresh
     // otherwise.
     for (var extensionRpc in isolate.extensionRPCs) {
-      _streamNotify(
+      streamNotify(
           'Isolate',
           Event()
             ..kind = EventKind.kServiceExtensionAdded
@@ -162,7 +171,7 @@ class ChromeProxyService implements VmServiceInterface {
   /// Clears out [_isolate] and all related cached information.
   void destroyIsolate() {
     if (_isolate == null) return;
-    _streamNotify(
+    streamNotify(
         'Isolate',
         Event()
           ..kind = EventKind.kIsolateExit
@@ -180,8 +189,8 @@ class ChromeProxyService implements VmServiceInterface {
 
   @override
   Future<Breakpoint> addBreakpoint(String isolateId, String scriptId, int line,
-      {int column}) {
-    throw UnimplementedError();
+      {int column}) async {
+    return debugger.addBreakpoint(isolateId, scriptId, line, column: column);
   }
 
   @override
@@ -501,7 +510,7 @@ function($argsString) {
 
   @override
   Future<ScriptList> getScripts(String isolateId) async {
-    var scripts = await _getScripts(isolateId);
+    var scripts = await scriptRefs(isolateId);
     return ScriptList()..scripts = scripts;
   }
 
@@ -518,7 +527,11 @@ function($argsString) {
       ..source = script;
   }
 
-  Future<List<ScriptRef>> _getScripts(String isolateId) async {
+  /// Internal method to list all scripts in the isolate.
+  ///
+  /// This is used as the underlying mechanism
+  /// for [getScripts].
+  Future<List<ScriptRef>> scriptRefs(String isolateId) async {
     var isolate = _getIsolate(isolateId);
     var scripts = <ScriptRef>[];
     for (var lib in isolate.libraries) {
@@ -527,6 +540,8 @@ function($argsString) {
       if (lib.id.startsWith('dart:') || lib.id.endsWith('.bootstrap')) continue;
       scripts.addAll((await _getLibrary(isolateId, lib.id)).scripts);
     }
+    // TODO(alanknight): Is this the same as the values in _scriptRefs after
+    // constructing all the libraries? Make that clearer.
     return scripts;
   }
 
@@ -613,7 +628,7 @@ function($argsString) {
 
   @override
   Future<ReloadReport> reloadSources(String isolateId,
-      {bool force, bool pause, String rootLibUri, String packagesUri}) {
+      {bool force, bool pause, String rootLibUri, String packagesUri}) async {
     throw UnimplementedError();
   }
 
@@ -673,7 +688,7 @@ function($argsString) {
   @override
   Future<Success> setVMName(String name) async {
     _vm.name = name;
-    _streamNotify(
+    streamNotify(
         'VM',
         Event()
           ..kind = EventKind.kVMUpdate
@@ -761,11 +776,11 @@ function($argsString) {
         } else {
           event.kind = EventKind.kPauseInterrupted;
         }
-        _streamNotify('Debug', event);
+        streamNotify('Debug', event);
       });
       resumeSubscription = tabConnection.debugger.onResumed.listen((e) {
         if (_isolate == null) return;
-        _streamNotify(
+        streamNotify(
             'Debug',
             Event()
               ..kind = EventKind.kResume
@@ -808,15 +823,15 @@ function($argsString) {
         case 'dart.developer.registerExtension':
           var service = event.args[1].value as String;
           _isolate.extensionRPCs.add(service);
-          _streamNotify(
+          streamNotify(
               'Isolate',
               Event()
                 ..kind = EventKind.kServiceExtensionAdded
                 ..extensionRPC = service
                 ..isolate = isolateRef);
           break;
         case 'dart.developer.postEvent':
-          _streamNotify(
+          streamNotify(
               'Extension',
               Event()
                 ..kind = EventKind.kExtension
@@ -836,7 +851,7 @@ function($argsString) {
             // up the library for a given instance to create it though.
             // https://github.com/dart-lang/sdk/issues/36771.
             ..classRef = ClassRef();
-          _streamNotify(
+          streamNotify(
               'Debug',
               Event()
                 ..kind = EventKind.kInspect
@@ -852,7 +867,7 @@ function($argsString) {
 
   /// Adds [event] to the stream with [streamId] if there is anybody listening
   /// on that stream.
-  void _streamNotify(String streamId, Event event) {
+  void streamNotify(String streamId, Event event) {
     var controller = _streamControllers[streamId];
     if (controller == null) return;
     controller.add(event);

dwds/lib/src/debugger.dart

@@ -0,0 +1,23 @@
+import 'dart:async';
+
+import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
+import 'package:vm_service_lib/vm_service_lib.dart';
+
+import 'chrome_proxy_service.dart';
+
+class Debugger {
+  Debugger(this.mainProxy);
+
+  ChromeProxyService mainProxy;
+
+  WipDebugger get chromeDebugger => mainProxy.tabConnection.debugger;
+
+  Future<Null> initialize() async {
+    await chromeDebugger.enable();
+  }
+
+  Future<Breakpoint> addBreakpoint(String isolateId, String scriptId, int line,
+      {int column}) async {
+    throw UnimplementedError();
+  }
+}

dwds/test/chrome_proxy_service_test.dart

@@ -29,19 +29,38 @@ void main() {
     await context.tearDown();
   });
 
-  test('addBreakPoint', () {
-    expect(() => service.addBreakpoint(null, null, null),
-        throwsUnimplementedError);
-  });
+  group('breakpoints', () {
+    VM vm;
+    Isolate isolate;
+    ScriptList scripts;
+    ScriptRef mainScript;
 
-  test('addBreakpointAtEntry', () {
-    expect(() => service.addBreakpointAtEntry(null, null),
-        throwsUnimplementedError);
-  });
+    setUp(() async {
+      vm = await service.getVM();
+      isolate = await service.getIsolate(vm.isolates.first.id) as Isolate;
+      scripts = await service.getScripts(isolate.id);
+      mainScript =
+          scripts.scripts.firstWhere((each) => each.uri.contains('main.dart'));
+    });
 
-  test('addBreakpointWithScriptUri', () {
-    expect(() => service.addBreakpointWithScriptUri(null, null, null),
-        throwsUnimplementedError);
+    test('addBreakPoint', () async {
+      // TODO: Reloading causes other tests to fail. Investigate.
+      //  await reload();
+      expect(() => service.addBreakpoint(isolate.id, mainScript.id, 19),
+          throwsUnimplementedError);
+      var breakpoints = isolate.breakpoints;
+      expect(breakpoints, isEmpty);
+    });
+
+    test('addBreakpointAtEntry', () {
+      expect(() => service.addBreakpointAtEntry(null, null),
+          throwsUnimplementedError);
+    });
+
+    test('addBreakpointWithScriptUri', () {
+      expect(() => service.addBreakpointWithScriptUri(null, null, null),
+          throwsUnimplementedError);
+    });
   });
 
   group('callServiceExtension', () {
@@ -358,15 +377,15 @@ void main() {
       pauseCompleter.complete();
     });
     var resumeCompleter = Completer();
-    var resumseSub = tabConnection.debugger.onResumed.listen((_) {
+    var resumeSub = tabConnection.debugger.onResumed.listen((_) {
       resumeCompleter.complete();
     });
     expect(await service.pause(isolateId), const TypeMatcher<Success>());
     await pauseCompleter.future;
     expect(await service.resume(isolateId), const TypeMatcher<Success>());
     await resumeCompleter.future;
     await pauseSub.cancel();
-    await resumseSub.cancel();
+    await resumeSub.cancel();
   });
 
   test('registerService', () async {