DevTools: Fix race condition in TextPrompt completions

third_party/WebKit/Source/devtools/front_end/ui/TextPrompt.js

Index: third_party/WebKit/Source/devtools/front_end/ui/TextPrompt.js
diff --git a/third_party/WebKit/Source/devtools/front_end/ui/TextPrompt.js b/third_party/WebKit/Source/devtools/front_end/ui/TextPrompt.js
index ffd47423e462767910bb2081411566c8cbaf4850..b40400ad7524c86ed10333a7930ab763874ed15f 100644
--- a/third_party/WebKit/Source/devtools/front_end/ui/TextPrompt.js
+++ b/third_party/WebKit/Source/devtools/front_end/ui/TextPrompt.js
@@ -45,6 +45,7 @@ WebInspector.TextPrompt = function(completions, stopCharacters)
     this._completionStopCharacters = stopCharacters || " =:[({;,!+-*/&|^<>.";
     this._autocompletionTimeout = WebInspector.TextPrompt.DefaultAutocompletionTimeout;
     this._title = "";
+    this._completionsCounter = 0;

[lushnikov, 2016/09/08 14:45:50]

let's name it _completionRequestId 

[einbinder, 2016/09/08 17:49:16]

Done.

 }
 
 WebInspector.TextPrompt.DefaultAutocompletionTimeout = 250;
@@ -380,7 +381,6 @@ WebInspector.TextPrompt.prototype = {
             clearTimeout(this._completeTimeout);
             delete this._completeTimeout;
         }
-        delete this._waitingForCompletions;
 
         if (!this.autoCompleteElement)
             return;
@@ -431,8 +431,7 @@ WebInspector.TextPrompt.prototype = {
         }
 
         var wordPrefixRange = selectionRange.startContainer.rangeOfWord(selectionRange.startOffset, this._completionStopCharacters, this._element, "backward");
-        this._waitingForCompletions = true;
-        this._loadCompletions(/** @type {!Element} */ (this._proxyElement), wordPrefixRange, force || false, this._completionsReady.bind(this, selection, wordPrefixRange, !!reverse, !!force));
+        this._loadCompletions(/** @type {!Element} */ (this._proxyElement), wordPrefixRange, force || false, this._completionsReady.bind(this, selection, wordPrefixRange, !!reverse, !!force, ++this._completionsCounter));
     },
 
     disableDefaultSuggestionForEmptyInput: function()
@@ -500,10 +499,11 @@ WebInspector.TextPrompt.prototype = {
      * @param {!Range} originalWordPrefixRange
      * @param {boolean} reverse
      * @param {boolean} force
+     * @param {number} completionsCounter

[lushnikov, 2016/09/08 14:45:50]

let's make it the very first one and name it completionRequestId

[einbinder, 2016/09/08 17:49:16]

Done.

      * @param {!Array.<string>} completions
      * @param {number=} selectedIndex
      */
-    _completionsReady: function(selection, originalWordPrefixRange, reverse, force, completions, selectedIndex)
+    _completionsReady: function(selection, originalWordPrefixRange, reverse, force, completionsCounter, completions, selectedIndex)
     {
         var prefix = originalWordPrefixRange.toString();
 
@@ -519,13 +519,11 @@ WebInspector.TextPrompt.prototype = {
                 annotatedCompletions = this.additionalCompletions(prefix).concat(annotatedCompletions);
         }
 
-        if (!this._waitingForCompletions || !annotatedCompletions.length) {
+        if (this._completionsCounter !== completionsCounter || !annotatedCompletions.length) {

[lushnikov, 2016/09/08 14:45:50]

let's bail out in the very beginning of the callback - we should not do anything
in case requestId has changed.

[einbinder, 2016/09/08 17:49:16]

Done.

             this.clearAutoComplete();
             return;
         }
 
-        delete this._waitingForCompletions;
-
         var selectionRange = selection.getRangeAt(0);
 
         var fullWordRange = this._createRange();