DevTools: Fix flickering hint when typing in TextPrompt

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 8ec159fc70c3c1f62ed4caa0c863fc533be1e904..401ec4125d1289276368b7a94fad47e4a7e45609 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 +45,8 @@ WebInspector.TextPrompt = function(completions, stopCharacters)
     this._completionStopCharacters = stopCharacters || " =:[({;,!+-*/&|^<>.";
     this._autocompletionTimeout = WebInspector.TextPrompt.DefaultAutocompletionTimeout;
     this._title = "";
+    this._previousText = "";
+    this._currentHintText = "";
     this._completionRequestId = 0;
 }
 
@@ -190,6 +192,7 @@ WebInspector.TextPrompt.prototype = {
         } else {
             this._element.textContent = x;
         }
+        this._previousText = this.userEnteredText();
 
         this.moveCaretToEndOfPrompt();
         this._element.scrollIntoView();
@@ -282,7 +285,16 @@ WebInspector.TextPrompt.prototype = {
      */
     _updateAutoComplete: function(force)

[lushnikov, 2016/10/19 23:36:47]

let's get rid of this method - it's confusing

[einbinder, 2016/10/20 01:21:44]

Done.

     {
-        this._clearAutocompleteElement();
+        var clearHint = true;
+        if (this._autocompleteElement) {

[lushnikov, 2016/10/19 23:36:47]

var hasCommonPrefix = text.startsWith(this._previousText) ||
this._previousText.startsWith(text);
var text = this.userEnteredText();
if (this._autocompleteElement && hasCommonPrefix)
    this._autocompleteElement.textContent =
this._currentHintText.substring(text.length);
else
    this._clearAutocompleteElement();
this._previousText = text;
this.autoCompleteSoon(force);

[einbinder, 2016/10/20 01:21:44]

Done.

+            var text = this.userEnteredText();
+            if (text.startsWith(this._previousText) || this._previousText.startsWith(text)) {
+                this._autocompleteElement.textContent = this._currentHintText.substring(text.length);
+                clearHint = false;
+            }
+        }
+        if (clearHint)
+            this._clearAutocompleteElement();
         this.autoCompleteSoon(force);
     },
 
@@ -356,6 +368,7 @@ WebInspector.TextPrompt.prototype = {
     {
         if (this._needUpdateAutocomplete)
             this._updateAutoComplete();
+        this._previousText = this.userEnteredText();
     },
 
     /**
@@ -381,10 +394,8 @@ WebInspector.TextPrompt.prototype = {
 
     _clearAutocompleteElement: function()
     {
-        if (this._completeTimeout) {
-            clearTimeout(this._completeTimeout);
-            delete this._completeTimeout;
-        }
+        this._clearAutocompleteTimeout();
+        this._completionRequestId++;

[lushnikov, 2016/10/19 23:36:47]

let's move this into _clearAutocompleteTimeout

[einbinder, 2016/10/20 01:21:44]

Done.

 
         if (!this._autocompleteElement)
             return;
@@ -395,6 +406,14 @@ WebInspector.TextPrompt.prototype = {
         delete this._userEnteredText;
     },
 
+    _clearAutocompleteTimeout: function()
+    {
+        if (this._completeTimeout) {
+            clearTimeout(this._completeTimeout);
+            delete this._completeTimeout;
+        }
+    },
+
     /**
      * @param {boolean=} force
      */
@@ -411,7 +430,7 @@ WebInspector.TextPrompt.prototype = {
      */
     complete: function(force, reverse)
     {
-        this.clearAutocomplete();
+        this._clearAutocompleteTimeout();
         var selection = this._element.getComponentSelection();
         var selectionRange = selection && selection.rangeCount ? selection.getRangeAt(0) : null;
         if (!selectionRange)
@@ -426,7 +445,7 @@ WebInspector.TextPrompt.prototype = {
         else if (!force) {
             // BUG72018: Do not show suggest box if caret is followed by a non-stop character.
             var wordSuffixRange = selectionRange.startContainer.rangeOfWord(selectionRange.endOffset, this._completionStopCharacters, this._element, "forward");
-            if (wordSuffixRange.toString().length)
+            if (wordSuffixRange.toString().length + this.userEnteredText().length - this.text().length)
                 shouldExit = true;
         }
         if (shouldExit) {
@@ -565,8 +584,10 @@ WebInspector.TextPrompt.prototype = {
             var prefixTextNode = createTextNode(prefixText);
             fullWordRange.insertNode(prefixTextNode);
 
-            this._autocompleteElement = createElementWithClass("span", "auto-complete-text");
+            if (!this._autocompleteElement)
+                this._autocompleteElement = createElementWithClass("span", "auto-complete-text");
             this._autocompleteElement.textContent = suffixText;
+            this._currentHintText = completionText;
 
             prefixTextNode.parentNode.insertBefore(this._autocompleteElement, prefixTextNode.nextSibling);