DevTools: support live coverage

third_party/WebKit/Source/devtools/front_end/coverage/CoverageDecorationManager.js

+// Copyright (c) 2017 The Chromium Authors. All rights reserved.

[dgozman, 2017/05/05 19:21:19]

no (c)

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+Coverage.CoverageDecorationManager = class {
+  /**
+   * @param {!Coverage.CoverageModel} coverageModel
+   */
+  constructor(coverageModel) {
+    this._coverageModel = coverageModel;
+    /** @type !Map<!Common.ContentProvider, ?TextUtils.Text> */
+    this._textByProvider = new Map();
+    /** @type !Multimap<!Common.ContentProvider, !Workspace.UISourceCode> */
+    this._uiSourceCodeByContentProvider = new Multimap();
+
+    for (var project of Workspace.workspace.projects()) {

[dgozman, 2017/05/05 19:21:19]

Use Workspace.uiSourceCodes().

+      for (var uiSourceCode of project.uiSourceCodes())
+        uiSourceCode.addLineDecoration(0, Coverage.CoverageDecorationManager._decoratorType, this);
+    }
+    Workspace.workspace.addEventListener(Workspace.Workspace.Events.UISourceCodeAdded, this._onUISourceCodeAdded, this);
+  }
+
+  dispose() {
+    for (var project of Workspace.workspace.projects()) {
+      for (var uiSourceCode of project.uiSourceCodes())

[dgozman, 2017/05/05 19:21:19]

ditto

+        uiSourceCode.removeDecorationsForType(Coverage.CoverageDecorationManager._decoratorType);
+    }
+    Workspace.workspace.removeEventListener(
+        Workspace.Workspace.Events.UISourceCodeAdded, this._onUISourceCodeAdded, this);
+  }
+
+  /**
+   * @param {!Array<!Coverage.CoverageInfo>} updatedEntries
+   */
+  update(updatedEntries) {
+    for (var entry of updatedEntries) {
+      for (var uiSourceCode of this._uiSourceCodeByContentProvider.get(entry.contentProvider())) {
+        uiSourceCode.removeDecorationsForType(Coverage.CoverageDecorationManager._decoratorType);
+        uiSourceCode.addLineDecoration(0, Coverage.CoverageDecorationManager._decoratorType, this);
+      }
+    }
+  }
+
+  /**
+   * @param {!Workspace.UISourceCode} uiSourceCode
+   * @return {!Promise<!Array<boolean>>}
+   */
+  async usageByLine(uiSourceCode) {
+    var result = [];
+    var sourceText = new TextUtils.Text(uiSourceCode.content() || '');
+    await this._updateTexts(uiSourceCode, sourceText);
+    var lineEndings = sourceText.lineEndings();
+    for (var line = 0; line < sourceText.lineCount(); ++line) {
+      var lineLength = lineEndings[line] - (line ? lineEndings[line - 1] : 0);
+      var startLocations = this._rawLocationsForSourceLocation(uiSourceCode, line, 0);
+      var endLocations = this._rawLocationsForSourceLocation(uiSourceCode, line, lineLength - 1);
+      var startLocationsByProvider = new Map(startLocations.map(location => [location.contentProvider, location]));

[alph, 2017/05/05 19:18:08]

can it have several locations with he same provider?

+      var used = false;
+      for (var end of endLocations) {

[alph, 2017/05/05 19:18:08]

nit: var used = endLocations.some(...);
;-)

+        var start = startLocationsByProvider.get(end.contentProvider);
+        var text = this._textByProvider.get(end.contentProvider);
+        if (!start || !text)
+          continue;
+        var textValue = text.value();
+        var startOffset = text.offsetFromPosition(start.line, start.column);
+        var endOffset = text.offsetFromPosition(end.line, end.column);
+        while (startOffset < endOffset && /\s/.test(textValue[startOffset]))

[alph, 2017/05/05 19:18:08]

Have you considered using substr and match with /^\s*/ ? I believe it creates a
sliced string with copy-on-write.

[alph, 2017/05/05 19:18:08]

<=

+          ++startOffset;
+        while (startOffset < endOffset && /\s/.test(textValue[endOffset]))

[alph, 2017/05/05 19:18:08]

ditto

+          --endOffset;
+        used = this._coverageModel.usageForRange(end.contentProvider, startOffset, endOffset);
+        if (used)
+          break;
+      }
+      result.push(used);
+    }
+    return result;
+  }
+
+  /**
+   * @param {!Workspace.UISourceCode} uiSourceCode
+   * @param {!TextUtils.Text} text
+   * @return !Promise

[alph, 2017/05/05 19:18:08]

I'm ok with using the clean syntax, but I know couple people that can be against
it. Please make sure there's a consensus.

+   */
+  _updateTexts(uiSourceCode, text) {
+    var promises = [];
+    for (var line = 0; line < text.lineCount(); ++line) {
+      for (var entry of this._rawLocationsForSourceLocation(uiSourceCode, line, 0)) {
+        if (!this._textByProvider.has(entry.contentProvider)) {

[alph, 2017/05/05 19:18:08]

if (...) continue;

+          this._textByProvider.set(entry.contentProvider, null);
+          this._uiSourceCodeByContentProvider.set(entry.contentProvider, uiSourceCode);
+          promises.push(this._updateTextForProvider(entry.contentProvider));
+        }
+      }
+    }
+    return Promise.all(promises);
+  }
+
+  /**
+   * @param {!Common.ContentProvider} contentProvider

[alph, 2017/05/05 19:18:08]

@return

+   */
+  async _updateTextForProvider(contentProvider) {
+    var content = await contentProvider.requestContent();
+    this._textByProvider.set(contentProvider, new TextUtils.Text(content));
+  }
+
+  /**
+   * @param {!Workspace.UISourceCode} uiSourceCode
+   * @param {number} line
+   * @param {number} column
+   * @return {!Array<!{contentProvider: !Common.ContentProvider, line: number, column: number}>}
+   */
+  _rawLocationsForSourceLocation(uiSourceCode, line, column) {
+    if (uiSourceCode.contentType().hasScripts()) {
+      var location = Bindings.debuggerWorkspaceBinding.uiLocationToRawLocation(uiSourceCode, line, column);
+      return location && location.script() ?

[dgozman, 2017/05/05 19:21:19]

html file could have both css and js locations.

+          [{contentProvider: location.script(), line: location.lineNumber, column: location.columnNumber}] :
+          [];
+    }
+    var rawStyleLocations =
+        Bindings.cssWorkspaceBinding.uiLocationToRawLocations(new Workspace.UILocation(uiSourceCode, line, 0));
+    var result = [];
+    for (var location of rawStyleLocations) {
+      if (!location.header())
+        continue;
+      result.push({contentProvider: location.header(), line: location.lineNumber, column: location.columnNumber});
+    }
+    return result;
+  }
+
+  /**
+   * @param {!Common.Event} event
+   */
+  _onUISourceCodeAdded(event) {
+    var uiSourceCode = /** @type !Workspace.UISourceCode */ (event.data);
+    uiSourceCode.addLineDecoration(0, Coverage.CoverageDecorationManager._decoratorType, this);
+  }
+};
+
+Coverage.CoverageDecorationManager._decoratorType = 'coverage';
+
+/**
+ * @implements {SourceFrame.UISourceCodeFrame.LineDecorator}
+ */
+Coverage.CoverageView.LineDecorator = class {
+  /**
+   * @override
+   * @param {!Workspace.UISourceCode} uiSourceCode
+   * @param {!TextEditor.CodeMirrorTextEditor} textEditor
+   */
+  decorate(uiSourceCode, textEditor) {
+    var decorations = uiSourceCode.decorationsForType(Coverage.CoverageDecorationManager._decoratorType);
+    if (!decorations.size) {
+      textEditor.uninstallGutter(Coverage.CoverageView.LineDecorator._gutterType);
+      return;
+    }
+    var decorationManager =
+        /** @type {!Coverage.CoverageDecorationManager} */ (decorations.values().next().value.data());
+    decorationManager.usageByLine(uiSourceCode).then(lineUsage => {
+      textEditor.operation(() => this._innerDecorate(textEditor, lineUsage));
+    });
+  }
+
+  /**
+   * @param {!TextEditor.CodeMirrorTextEditor} textEditor
+   * @param {!Array<boolean>} lineUsage
+   */
+  _innerDecorate(textEditor, lineUsage) {
+    var gutterType = Coverage.CoverageView.LineDecorator._gutterType;
+    textEditor.uninstallGutter(gutterType);
+    textEditor.installGutter(gutterType, false);
+    for (var line = 0; line < lineUsage.length; ++line) {
+      var className = lineUsage[line] ? 'text-editor-coverage-used-marker' : 'text-editor-coverage-unused-marker';
+      textEditor.setGutterDecoration(line, gutterType, createElementWithClass('div', className));
+    }
+  }
+};
+
+Coverage.CoverageView.LineDecorator._gutterType = 'CodeMirror-gutter-coverage';