Bug 827604 - Pseudoclass lock isn't clearing; r=dcamp

browser/devtools/inspector/InspectorPanel.jsm

@@ -65,6 +65,8 @@ InspectorPanel.prototype = {
     this._selection = new Selection();
     this.onNewSelection = this.onNewSelection.bind(this);
     this.selection.on("new-node", this.onNewSelection);
+    this.onBeforeNewSelection = this.onBeforeNewSelection.bind(this);
+    this.selection.on("before-new-node", this.onBeforeNewSelection);
     this.onDetached = this.onDetached.bind(this);
     this.selection.on("detached", this.onDetached);
 
@@ -319,6 +321,17 @@ InspectorPanel.prototype = {
     this.cancelLayoutChange();
   },
 
+  /**
+   * When a new node is selected, before the selection has changed.
+   */
+  onBeforeNewSelection: function InspectorPanel_onBeforeNewSelection(event,
+                                                                     node) {
+    if (this.breadcrumbs.indexOf(node) == -1) {
+      // only clear locks if we'd have to update breadcrumbs
+      this.clearPseudoClasses();
+    }
+  },
+
   /**
    * When a node is deleted, select its parent node.
    */
@@ -367,6 +380,7 @@ InspectorPanel.prototype = {
     this.nodemenu.removeEventListener("popuphiding", this._resetNodeMenu, true);
     this.breadcrumbs.destroy();
     this.selection.off("new-node", this.onNewSelection);
+    this.selection.off("before-new-node", this.onBeforeNewSelection);
     this.selection.off("detached", this.onDetached);
     this._destroyMarkup();
     this._selection.destroy();
@@ -500,6 +514,15 @@ InspectorPanel.prototype = {
     this.selection.emit("pseudoclass");
   },
 
+  /**
+   * Clear any pseudo-class locks applied to the current hierarchy.
+   */
+  clearPseudoClasses: function InspectorPanel_clearPseudoClasses() {
+    this.breadcrumbs.nodeHierarchy.forEach(function(crumb) {
+      DOMUtils.clearPseudoClassLocks(crumb.node);
+    });
+  },
+
   /**
    * Toggle the highlighter when ruleview is hovered.
    */

browser/devtools/inspector/Selection.jsm

@@ -42,6 +42,7 @@ this.EXPORTED_SYMBOLS = ["Selection"];
  *
  * Events:
  *   "new-node" when the inner node changed
+ *   "before-new-node" when the inner node is set to change
  *   "attribute-changed" when an attribute is changed (only if tracked)
  *   "detached" when the node (or one of its parents) is removed from the document (only if tracked)
  *   "reparented" when the node (or one of its parents) is moved under a different node (only if tracked)
@@ -126,6 +127,7 @@ Selection.prototype = {
   setNode: function SN_setNode(value, reason="unknown") {
     this.reason = reason;
     if (value !== this._node) {
+      this.emit("before-new-node", value, reason);
       let previousNode = this._node;
       this._detachEvents();
       this._node = value;

browser/devtools/inspector/test/browser_inspector_pseudoclass_lock.js

@@ -8,7 +8,7 @@ let TargetFactory = tempScope.TargetFactory;
 let DOMUtils = Cc["@mozilla.org/inspector/dom-utils;1"].getService(Ci.inIDOMUtils);
 
 let doc;
-let div;
+let parentDiv, div, div2;
 let inspector;
 let ruleview;
 
@@ -30,16 +30,24 @@ function test()
 
 function createDocument()
 {
+  parentDiv = doc.createElement("div");
+  parentDiv.textContent = "parent div";
+
   div = doc.createElement("div");
   div.textContent = "test div";
 
+  div2 = doc.createElement("div");
+  div2.textContent = "test div2";
+
   let head = doc.getElementsByTagName('head')[0];
   let style = doc.createElement('style');
   let rules = doc.createTextNode('div { color: red; } div:hover { color: blue; }');
 
   style.appendChild(rules);
   head.appendChild(style);
-  doc.body.appendChild(div);
+  parentDiv.appendChild(div);
+  parentDiv.appendChild(div2);
+  doc.body.appendChild(parentDiv);
 
   openInspector(selectNode);
 }
@@ -71,10 +79,31 @@ function performTests()
   // toggle it back on
   inspector.togglePseudoClass(pseudo);
 
+  testNavigate();
+
   // close the inspector
   finishUp();
 }
 
+function testNavigate()
+{
+  inspector.selection.setNode(parentDiv);
+
+  // make sure it's still on after naving to parent
+  is(DOMUtils.hasPseudoClassLock(div, pseudo), true,
+       "pseudo-class lock is still applied after inspecting ancestor");
+
+  inspector.selection.setNode(div2);
+
+  // make sure it's removed after naving to a non-hierarchy node
+  is(DOMUtils.hasPseudoClassLock(div, pseudo), false,
+       "pseudo-class lock is removed after inspecting sibling node");
+
+  // toggle it back on
+  inspector.selection.setNode(div);
+  inspector.togglePseudoClass(pseudo);
+}
+
 function testAdded()
 {
   // lock is applied to it and ancestors