DevTools: properly restore selected DOMNode in Elements panel.

third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js

Index: third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js b/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
index 3686992e756f08f1dacd49923786a4e897233559..72dde7ec6ee865e92c9747e62bf6e1720fdbccb5 100644
--- a/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
+++ b/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
@@ -329,9 +329,6 @@ WebInspector.ElementsPanel.prototype = {
                 this._treeOutlines[i].selectDOMNode(null);
         }
 
-        if (!selectedNode && this._lastValidSelectedNode)
-            this._selectedPathOnReset = this._lastValidSelectedNode.path();
-
         this._breadcrumbs.setSelectedNode(selectedNode);
 
         WebInspector.context.setFlavor(WebInspector.DOMNode, selectedNode);
@@ -339,7 +336,10 @@ WebInspector.ElementsPanel.prototype = {
         if (!selectedNode)
             return;
         selectedNode.setAsInspectedNode();
-        this._lastValidSelectedNode = selectedNode;
+        if (!this._isSettingDefaultSelection) {
+            this._selectedNodeOnReset = selectedNode;
+            this._hasNonDefaultSelectedNode = true;
+        }
 
         var executionContexts = selectedNode.target().runtimeModel.executionContexts();
         var nodeFrameId = selectedNode.frameId();
@@ -382,53 +382,65 @@ WebInspector.ElementsPanel.prototype = {
             return;
         }
 
+        this._hasNonDefaultSelectedNode = false;
         WebInspector.domBreakpointsSidebarPane.restoreBreakpoints(inspectedRootDocument);
 
-        /**
-         * @this {WebInspector.ElementsPanel}
-         * @param {?WebInspector.DOMNode} candidateFocusNode
-         */
-        function selectNode(candidateFocusNode)
-        {
-            if (!candidateFocusNode)
-                candidateFocusNode = inspectedRootDocument.body || inspectedRootDocument.documentElement;
-
-            if (!candidateFocusNode)
-                return;
+        var defaultSelection = inspectedRootDocument.body || inspectedRootDocument.documentElement;
+        if (this._omitDefaultSelection || !defaultSelection)
+            return;
 
-            if (!this._pendingNodeReveal) {
-                this.selectDOMNode(candidateFocusNode);
-                if (treeOutline.selectedTreeElement)
-                    treeOutline.selectedTreeElement.expand();
-            }
-        }
+        this._restoreNode(domModel, this._selectedNodeOnReset)
+            .then(onNodeRestored.bind(this, this._selectedNodeOnReset))

[dgozman, 2016/10/19 01:10:38]

missing semicolon

[lushnikov, 2016/10/19 20:52:11]

Done.

 
         /**
-         * @param {?DOMAgent.NodeId} nodeId
+         * @param {?WebInspector.DOMNode} staleNode
+         * @param {?WebInspector.DOMNode} restoredNode
          * @this {WebInspector.ElementsPanel}
          */
-        function selectLastSelectedNode(nodeId)
+        function onNodeRestored(staleNode, restoredNode)
         {
-            if (this.selectedDOMNode()) {
-                // Focused node has been explicitly set while reaching out for the last selected node.
+            if (staleNode !== this._selectedNodeOnReset)
                 return;
+            if (restoredNode) {
+                this._preselectNode(restoredNode);
+                this._lastSelectedNodeSelectedForTest();
+            } else {
+                this._preselectNode(defaultSelection);

[dgozman, 2016/10/19 01:10:38]

Should recalc default selection.

[lushnikov, 2016/10/19 20:52:11]

Done.

             }
-            var node = nodeId ? domModel.nodeForId(nodeId) : null;
-            selectNode.call(this, node);
-            this._lastSelectedNodeSelectedForTest();
         }
+    },
 
-        if (this._omitDefaultSelection)
-            return;
+    _lastSelectedNodeSelectedForTest: function() { },
 
-        if (this._selectedPathOnReset)
-            domModel.pushNodeByPathToFrontend(this._selectedPathOnReset, selectLastSelectedNode.bind(this));
-        else
-            selectNode.call(this, null);
-        delete this._selectedPathOnReset;
+    /**
+     * @param {!WebInspector.DOMNode} node
+     */
+    _preselectNode: function(node)

[dgozman, 2016/10/19 01:10:38]

_setDefaultSelectedNode

[dgozman, 2016/10/19 01:10:38]

Let's make this one responsible for default selection as well.

[lushnikov, 2016/10/19 20:52:11]

The default selection seems to fit better in the onNodeRestored method;
I left it there.

[lushnikov, 2016/10/19 20:52:11]

Done.

+    {
+        if (this._hasNonDefaultSelectedNode || this._pendingNodeReveal)
+            return;
+        var treeOutline = WebInspector.ElementsTreeOutline.forDOMModel(node.domModel());
+        if (!treeOutline)
+            return;
+        this._isSettingDefaultSelection = true;

[dgozman, 2016/10/19 01:10:38]

nit: _isSettingDefaultSelectedNode

[lushnikov, 2016/10/19 20:52:11]

Done.

+        this.selectDOMNode(node);
+        this._isSettingDefaultSelection = false;
+        if (treeOutline.selectedTreeElement)
+            treeOutline.selectedTreeElement.expand();
     },
 
-    _lastSelectedNodeSelectedForTest: function() { },
+    /**
+     * @param {!WebInspector.DOMModel} domModel
+     * @param {?WebInspector.DOMNode} staleNode
+     * @return {!Promise<?WebInspector.DOMNode>}
+     */
+    _restoreNode: function(domModel, staleNode)

[dgozman, 2016/10/19 01:10:38]

Let's make this inner function of _documentUpdated.

[lushnikov, 2016/10/19 20:52:11]

Done.

+    {
+        var nodePath = staleNode ? staleNode.path() : null;
+        if (!nodePath)
+            return Promise.resolve(/** @type {?WebInspector.DOMNode} */(null));
+        return domModel.pushNodeByPathToFrontendPromise(nodePath);

[dgozman, 2016/10/19 01:10:38]

Let's maybe use callback version?

[lushnikov, 2016/10/19 20:52:11]

Done.

+    },
 
     /**
      * @override
@@ -719,7 +731,7 @@ WebInspector.ElementsPanel.prototype = {
 
         var treeOutline = null;
         for (var i = 0; i < this._treeOutlines.length; ++i) {
-            if (this._treeOutlines[i].selectedDOMNode() === this._lastValidSelectedNode)
+            if (this._treeOutlines[i].selectedDOMNode())
                 treeOutline = this._treeOutlines[i];
         }
         if (!treeOutline)