DevTools: [Documentation] Add property token autodetection

Source/devtools/front_end/documentation/DocumentationView.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @constructor
  * @extends {WebInspector.VBox}
  */
 WebInspector.DocumentationView = function()
 {
@@ skipping 27 matching lines @@
     /**
      * @param {!Event} event
      * @param {!WebInspector.ContextMenu} contextMenu
      * @param {!Object} target
      */
     appendApplicableItems: function(event, contextMenu, target)
     {
         if (!(target instanceof WebInspector.CodeMirrorTextEditor))
             return;
         var textEditor = /** @type {!WebInspector.CodeMirrorTextEditor} */ (target);
-        var selection = textEditor.selection();
-        if (!selection || selection.isEmpty() || selection.startLine !== selection.endLine)
-            return;
-        var selectedText = textEditor.copyRange(selection);
+        var propertyName;
+        var textSelection = textEditor.selection().normalize();
+
+        if (textSelection && !textSelection.isEmpty() && textSelection.startLine === textSelection.endLine) {
+            propertyName = textEditor.copyRange(textSelection);
+        } else {
+            var textPosition = textEditor.coordinatesToCursorPosition(event.x, event.y);

[lushnikov, 2014/08/14 11:44:14]

let's switch to cursor position instead - context menu could be summoned via
keyboard. 

[semeny, 2014/08/14 12:40:49]

Done.

+            var token = textEditor.tokenAtTextPosition(textPosition.startLine, textPosition.startColumn);

[lushnikov, 2014/08/14 11:44:14]

you're not only interested in token existence, but in existence of documentation
per token.
I.e. if both left and right tokens exist, but there's no documentation for left
token, and there's one for right, you should use right.

[semeny, 2014/08/14 12:40:49]

Done.

+            if (!token) {
+                if (textPosition.startColumn > 0)
+                    token = textEditor.tokenAtTextPosition(textPosition.startLine, textPosition.startColumn - 1);
+                if (!token)
+                    return;
+            }
+            var line = textEditor.line(textPosition.startLine);
+            propertyName = line.substring(token.startColumn, token.endColumn);
+        }
+
         var urlProvider = new WebInspector.DocumentationURLProvider();
-        var descriptors = urlProvider.itemDescriptors(selectedText);
+        var descriptors = urlProvider.itemDescriptors(propertyName);
         if (!descriptors.length)
             return;
         if (descriptors.length === 1) {
             var formatString = WebInspector.useLowerCaseMenuTitles() ? "Show documentation for %s.%s" : "Show Documentation for %s.%s";
-            contextMenu.appendItem(WebInspector.UIString(formatString, descriptors[0].name, selectedText), WebInspector.DocumentationView.showDocumentationURL.bind(null, descriptors[0].url));
+            contextMenu.appendItem(WebInspector.UIString(formatString, descriptors[0].name, propertyName), WebInspector.DocumentationView.showDocumentationURL.bind(null, descriptors[0].url));
             return;
         }
         var subMenuItem = contextMenu.appendSubMenuItem(WebInspector.UIString(WebInspector.useLowerCaseMenuTitles() ? "Show documentation for..." : "Show Documentation for..."));
         for (var i = 0; i < descriptors.length; ++i)
-            subMenuItem.appendItem(String.sprintf("%s.%s", descriptors[i].name, selectedText), WebInspector.DocumentationView.showDocumentationURL.bind(null, descriptors[i].url));
+            subMenuItem.appendItem(String.sprintf("%s.%s", descriptors[i].name, propertyName), WebInspector.DocumentationView.showDocumentationURL.bind(null, descriptors[i].url));
     }
 }