[DevTools] Support async step in from arbitrary position

third_party/WebKit/Source/devtools/front_end/sources/JavaScriptSourceFrame.js

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 498 matching lines @@
 
   /**
    * @param {!MouseEvent} event
    */
   _onMouseMove(event) {
     if (this._executionLocation && this._controlDown && UI.KeyboardShortcut.eventHasCtrlOrMeta(event)) {
       if (!this._continueToLocationDecorations)
         this._showContinueToLocations();
     }
     if (this._continueToLocationDecorations) {
-      this.textEditor.element.classList.toggle(
-          'source-frame-async-step-in-hovered',
-          !!event.target.enclosingNodeOrSelfWithClass('source-frame-async-step-in'));
+      var textPosition = this.textEditor.coordinatesToCursorPosition(event.x, event.y);
+      var hovering = !!event.target.enclosingNodeOrSelfWithClass('source-frame-async-step-in');
+      this._setAsyncStepInHoveredLine(textPosition ? textPosition.startLine : null, hovering);
     }
   }
 
   /**
+   * @param {?number} line
+   * @param {boolean} hovered
+   */
+  _setAsyncStepInHoveredLine(line, hovered) {
+    if (this._asyncStepInHoveredLine === line && this._asyncStepInHovered === hovered)
+      return;
+    if (this._asyncStepInHovered && this._asyncStepInHoveredLine)
+      this.textEditor.toggleLineClass(this._asyncStepInHoveredLine, 'source-frame-async-step-in-hovered', false);
+    this._asyncStepInHoveredLine = line;
+    this._asyncStepInHovered = hovered;
+    if (this._asyncStepInHovered && this._asyncStepInHoveredLine)
+      this.textEditor.toggleLineClass(this._asyncStepInHoveredLine, 'source-frame-async-step-in-hovered', true);
+  }
+
+  /**
    * @param {!MouseEvent} event
    */
   _onMouseDown(event) {
     if (!this._executionLocation || !UI.KeyboardShortcut.eventHasCtrlOrMeta(event))
       return;
     if (!this._continueToLocationDecorations)
       return;
     event.consume();
     var textPosition = this.textEditor.coordinatesToCursorPosition(event.x, event.y);
     if (!textPosition)
@@ skipping 181 matching lines @@
         var highlightRange = new TextUtils.TextRange(lineNumber, token.startColumn, lineNumber, token.endColumn - 1);
         var decoration = this.textEditor.highlightRange(highlightRange, 'source-frame-continue-to-location');
         this._continueToLocationDecorations.set(decoration, location.continueToLocation.bind(location));
         if (location.type === Protocol.Debugger.BreakLocationType.Call)
           previousCallLine = lineNumber;
 
         var isAsyncCall = (line[token.startColumn - 1] === '.' && tokenContent === 'then') ||
             tokenContent === 'setTimeout' || tokenContent === 'setInterval';
         var isCurrentPosition = this._executionLocation && lineNumber === this._executionLocation.lineNumber &&
             location.columnNumber === this._executionLocation.columnNumber;
-        if (location.type === Protocol.Debugger.BreakLocationType.Call && isAsyncCall && isCurrentPosition) {
+        if (location.type === Protocol.Debugger.BreakLocationType.Call && isAsyncCall) {
           var functionPosition = line.indexOf('(', token.endColumn);
           if (functionPosition !== -1) {
             functionPosition++;
             while (functionPosition < line.length && line[functionPosition] === ' ')
               functionPosition++;
             var nextToken = this.textEditor.tokenAtTextPosition(lineNumber, functionPosition);
             if (nextToken) {
               if (line.substring(nextToken.startColumn, nextToken.endColumn) === '(') {
                 var closeParen = line.indexOf(')', nextToken.endColumn);
                 nextToken.endColumn = closeParen === -1 ? line.length : closeParen + 1;
               }
               highlightRange =
                   new TextUtils.TextRange(lineNumber, nextToken.startColumn, lineNumber, nextToken.endColumn - 1);
               decoration = this.textEditor.highlightRange(highlightRange, 'source-frame-async-step-in');
-              this._continueToLocationDecorations.set(decoration, () => {
-                debuggerModel.scheduleStepIntoAsync();
-                debuggerModel.stepInto();
-              });
+              this._continueToLocationDecorations.set(
+                  decoration, this._asyncStepIn.bind(this, location, isCurrentPosition));
             }
           }
         }
       }
     }
   }
 
   /**
+   * @param {!SDK.DebuggerModel.BreakLocation} location
+   * @param {boolean} isCurrentPosition
+   */
+  _asyncStepIn(location, isCurrentPosition) {
+    if (!isCurrentPosition)
+      location.continueToLocation(asyncStepIn);
+    else
+      asyncStepIn();
+
+    function asyncStepIn() {
+      location.debuggerModel.scheduleStepIntoAsync();
+      location.debuggerModel.stepInto();
+    }
+  }
+
+  /**
    * @param {!SDK.DebuggerModel.CallFrame} callFrame
    * @param {?Array.<!SDK.RemoteObjectProperty>} properties
    * @param {?Array.<!SDK.RemoteObjectProperty>} internalProperties
    */
   _prepareScopeVariables(callFrame, properties, internalProperties) {
     if (!properties || !properties.length || properties.length > 500 || !this.isShowing()) {
       this._clearValueWidgets();
       return;
     }
 
@@ skipping 149 matching lines @@
     });
   }
 
   _clearContinueToLocationsNoRestore() {
     if (!this._continueToLocationDecorations)
       return;
     this.textEditor.operation(() => {
       for (var decoration of this._continueToLocationDecorations.keys())
         this.textEditor.removeHighlight(decoration);
       this._continueToLocationDecorations = null;
-      this.textEditor.element.classList.remove('source-frame-async-step-in-hovered');
+      this._setAsyncStepInHoveredLine(null, false);
     });
   }
 
   _clearContinueToLocations() {
     if (!this._continueToLocationDecorations)
       return;
     this.textEditor.operation(() => {
       this.textEditor.showExecutionLineBackground();
       this._generateValuesInSource();
       this._clearContinueToLocationsNoRestore();
@@ skipping 643 matching lines @@
       return;
     this.bookmark.clear();
     this.bookmark = null;
   }
 };
 
 Sources.JavaScriptSourceFrame.BreakpointDecoration.bookmarkSymbol = Symbol('bookmark');
 Sources.JavaScriptSourceFrame.BreakpointDecoration._elementSymbolForTest = Symbol('element');
 
 Sources.JavaScriptSourceFrame.continueToLocationDecorationSymbol = Symbol('bookmark');