Merge "Cut dep from highlight onto comment model"
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html
index e26201a..e77eb57 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html
@@ -29,7 +29,7 @@
     </div>
     <gr-ranged-comment-layer
         id="rangeLayer"
-        comments="[[comments]]"></gr-ranged-comment-layer>
+        comment-ranges="[[commentRanges]]"></gr-ranged-comment-layer>
     <gr-syntax-layer
         id="syntaxLayer"
         diff="[[diff]]"></gr-syntax-layer>
@@ -109,7 +109,6 @@
           changeNum: String,
           patchNum: String,
           viewMode: String,
-          comments: Object,
           isImageDiff: Boolean,
           baseImage: Object,
           revisionImage: Object,
@@ -125,6 +124,10 @@
           _groups: Array,
           _layers: Array,
           _showTabs: Boolean,
+          /** @type {!Array<!Gerrit.HoveredRange>} */
+          commentRanges: {
+            type: Array,
+          },
         },
 
         get diffElement() {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html
index a855833..c277f34 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html
@@ -389,7 +389,7 @@
     test('_handlePreferenceError called with invalid preference', () => {
       sandbox.stub(element, '_handlePreferenceError');
       const prefs = {tab_size: 0};
-      element._getDiffBuilder(element.diff, element.comments, prefs);
+      element._getDiffBuilder(element.diff, undefined, prefs);
       assert.isTrue(element._handlePreferenceError.lastCall
           .calledWithExactly('tab size'));
     });
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js
index b80c210..85ba202 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js
@@ -21,7 +21,11 @@
     is: 'gr-diff-highlight',
 
     properties: {
-      comments: Object,
+      /** @type {!Array<!Gerrit.HoveredRange>} */
+      commentRanges: {
+        type: Array,
+        notify: true,
+      },
       loggedIn: Boolean,
       /**
        * querySelector can return null, so needs to be nullable.
@@ -71,35 +75,44 @@
     },
 
     _handleCommentMouseOver(e) {
-      const comment = e.detail.comment;
-      if (!comment.range) { return; }
-      const lineEl = this.diffBuilder.getLineElByChild(e.target);
-      const side = this.diffBuilder.getSideByLineEl(lineEl);
-      const index = this._indexOfComment(side, comment);
+      const threadEl = Polymer.dom(e).localTarget;
+      const index = this._indexForThreadEl(threadEl);
+
       if (index !== undefined) {
-        this.set(['comments', side, index, '__hovering'], true);
+        this.set(['commentRanges', index, 'hovering'], true);
       }
     },
 
     _handleCommentMouseOut(e) {
-      const comment = e.detail.comment;
-      if (!comment.range) { return; }
-      const lineEl = this.diffBuilder.getLineElByChild(e.target);
-      const side = this.diffBuilder.getSideByLineEl(lineEl);
-      const index = this._indexOfComment(side, comment);
+      const threadEl = Polymer.dom(e).localTarget;
+      const index = this._indexForThreadEl(threadEl);
+
       if (index !== undefined) {
-        this.set(['comments', side, index, '__hovering'], false);
+        this.set(['commentRanges', index, 'hovering'], false);
       }
     },
 
-    _indexOfComment(side, comment) {
-      const idProp = comment.id ? 'id' : '__draftID';
-      for (let i = 0; i < this.comments[side].length; i++) {
-        if (comment[idProp] &&
-            this.comments[side][i][idProp] === comment[idProp]) {
-          return i;
-        }
+    _indexForThreadEl(threadEl) {
+      const side = threadEl.getAttribute('comment-side');
+      const range = JSON.parse(threadEl.getAttribute('range'));
+
+      if (!range) return undefined;
+
+      return this._indexOfCommentRange(side, range);
+    },
+
+    _indexOfCommentRange(side, range) {
+      function rangesEqual(a, b) {
+        if (!a && !b) { return true; }
+        if (!a || !b) { return false; }
+        return a.start_line === b.start_line &&
+            a.start_character === b.start_character &&
+            a.end_line === b.end_line &&
+            a.end_character === b.end_character;
       }
+
+      return this.commentRanges.findIndex(commentRange =>
+          commentRange.side === side && rangesEqual(commentRange.range, range));
     },
 
     /**
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html
index d3ae66b..23de407 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html
@@ -205,7 +205,7 @@
 
       test('comment-mouse-over from ranged comment causes set', () => {
         sandbox.stub(element, 'set');
-        sandbox.stub(element, '_indexOfComment').returns(0);
+        sandbox.stub(element, '_indexForThreadEl').returns(0);
         element.fire('comment-mouse-over', {comment: {range: {}}});
         assert.isTrue(element.set.called);
       });
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
index 7f7ec72..862db10 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
@@ -280,10 +280,10 @@
         <gr-diff-highlight
             id="highlights"
             logged-in="[[loggedIn]]"
-            comments="{{comments}}">
+            comment-ranges="{{_commentRanges}}">
           <gr-diff-builder
               id="diffBuilder"
-              comments="[[comments]]"
+              comment-ranges="[[_commentRanges]]"
               project-name="[[projectName]]"
               diff="[[diff]]"
               diff-path="[[path]]"
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js
index 8bec77e..f87e46f 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js
@@ -43,6 +43,11 @@
    *             end_line: number, end_character: number}} */
   Gerrit.Range;
 
+  function isThreadEl(node) {
+    return node.nodeType === Node.ELEMENT_NODE &&
+        node.classList.contains('comment-thread');
+  }
+
   Polymer({
     is: 'gr-diff',
 
@@ -100,6 +105,11 @@
         type: Object,
         value: {left: [], right: []},
       },
+      /** @type {!Array<!Gerrit.HoveredRange>} */
+      _commentRanges: {
+        type: Array,
+        value: [],
+      },
       lineWrapping: {
         type: Boolean,
         value: false,
@@ -185,7 +195,19 @@
 
       _diffLength: Number,
 
-      /** @type {?PolymerDomApi.ObserveHandle} */
+      /**
+       * Observes comment nodes added or removed after the initial render.
+       * Can be used to unregister when the entire diff is (re-)rendered or upon
+       * detachment.
+       * @type {?PolymerDomApi.ObserveHandle}
+       */
+      _incrementalNodeObserver: Object,
+
+      /**
+       * Observes comment nodes added or removed at any point.
+       * Can be used to unregister upon detachment.
+       * @type {?PolymerDomApi.ObserveHandle}
+       */
       _nodeObserver: Object,
     },
 
@@ -201,10 +223,36 @@
       'render-content': '_handleRenderContent',
     },
 
+    attached() {
+      this._updateRangesWhenNodesChange();
+    },
+
     detached() {
+      this._unobserveIncrementalNodes();
       this._unobserveNodes();
     },
 
+    _updateRangesWhenNodesChange() {
+      function commentRangeFromThreadEl(threadEl) {
+        const side = threadEl.getAttribute('comment-side');
+        const range = JSON.parse(threadEl.getAttribute('range'));
+        return {side, range, hovering: false};
+      }
+
+      this._nodeObserver = Polymer.dom(this).observeNodes(info => {
+        const addedThreadEls = info.addedNodes.filter(isThreadEl);
+        const addedCommentRanges = addedThreadEls
+            .map(commentRangeFromThreadEl)
+            .filter(({range}) => range);
+        this.push('_commentRanges', ...addedCommentRanges);
+        // In principal we should also handle removed nodes, but I have not
+        // figured out how to do that yet without also catching all the removals
+        // caused by further redistribution. Right now, comments are never
+        // removed by no longer slotting them in, so I decided to not handle
+        // this situation until it occurs.
+      });
+    },
+
     /** Cancel any remaining diff builder rendering work. */
     cancel() {
       this.$.diffBuilder.cancel();
@@ -577,7 +625,7 @@
     },
 
     _renderDiffTable() {
-      this._unobserveNodes();
+      this._unobserveIncrementalNodes();
       if (!this.prefs) {
         this.dispatchEvent(new CustomEvent('render', {bubbles: true}));
         return;
@@ -595,9 +643,8 @@
     },
 
     _handleRenderContent() {
-      this._nodeObserver = Polymer.dom(this).observeNodes(info => {
-        const addedThreadEls = info.addedNodes.filter(
-            node => node.nodeType === Node.ELEMENT_NODE);
+      this._incrementalNodeObserver = Polymer.dom(this).observeNodes(info => {
+        const addedThreadEls = info.addedNodes.filter(isThreadEl);
         // In principal we should also handle removed nodes, but I have not
         // figured out how to do that yet without also catching all the removals
         // caused by further redistribution. Right now, comments are never
@@ -616,6 +663,12 @@
       });
     },
 
+    _unobserveIncrementalNodes() {
+      if (this._incrementalNodeObserver) {
+        Polymer.dom(this).unobserveNodes(this._incrementalNodeObserver);
+      }
+    },
+
     _unobserveNodes() {
       if (this._nodeObserver) {
         Polymer.dom(this).unobserveNodes(this._nodeObserver);
@@ -633,7 +686,7 @@
     },
 
     clearDiffContent() {
-      this._unobserveNodes();
+      this._unobserveIncrementalNodes();
       this.$.diffTable.innerHTML = null;
     },
 
diff --git a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js
index db14fc8..fa488f0 100644
--- a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js
+++ b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js
@@ -17,31 +17,34 @@
 (function() {
   'use strict';
 
-  const HOVER_PATH_PATTERN = /^comments\.(left|right)\.\#(\d+)\.__hovering$/;
-  const SPLICE_PATH_PATTERN = /^comments\.(left|right)\.splices$/;
+  const HOVER_PATH_PATTERN = /^commentRanges\.\#(\d+)\.hovering$/;
 
   const RANGE_HIGHLIGHT = 'range';
   const HOVER_HIGHLIGHT = 'rangeHighlight';
 
   const NORMALIZE_RANGE_EVENT = 'normalize-range';
 
+  /** @typedef {{side: string, range: Gerrit.Range, hovering: boolean}} */
+  Gerrit.HoveredRange;
+
   Polymer({
     is: 'gr-ranged-comment-layer',
 
     properties: {
-      comments: Object,
+      /** @type {!Array<!Gerrit.HoveredRange>} */
+      commentRanges: Array,
       _listeners: {
         type: Array,
         value() { return []; },
       },
-      _commentMap: {
+      _rangesMap: {
         type: Object,
-        value() { return {left: [], right: []}; },
+        value() { return {left: {}, right: {}}; },
       },
     },
 
     observers: [
-      '_handleCommentChange(comments.*)',
+      '_handleCommentRangesChange(commentRanges.*)',
     ],
 
     /**
@@ -93,97 +96,78 @@
     },
 
     /**
-     * Handle change in the comments by updating the comment maps and by
+     * Handle change in the ranges by updating the ranges maps and by
      * emitting appropriate update notifications.
      * @param {Object} record The change record.
      */
-    _handleCommentChange(record) {
-      if (!record.path) { return; }
+    _handleCommentRangesChange(record) {
+      if (!record) return;
 
       // If the entire set of comments was changed.
-      if (record.path === 'comments') {
-        this._commentMap.left = this._computeCommentMap(this.comments.left);
-        this._commentMap.right = this._computeCommentMap(this.comments.right);
-        return;
+      if (record.path === 'commentRanges') {
+        this._rangesMap = {left: {}, right: {}};
+        for (const {side, range, hovering} of record.value) {
+          this._updateRangesMap(
+              side, range, hovering, (forLine, start, end, hovering) => {
+                forLine.push({start, end, hovering});
+              });
+        }
       }
 
       // If the change only changed the `hovering` property of a comment.
-      let match = record.path.match(HOVER_PATH_PATTERN);
-      let side;
-
+      const match = record.path.match(HOVER_PATH_PATTERN);
       if (match) {
-        side = match[1];
-        const index = match[2];
-        const comment = this.comments[side][index];
-        if (comment && comment.range) {
-          this._commentMap[side] = this._computeCommentMap(this.comments[side]);
-          this._notifyUpdateRange(
-              comment.range.start_line, comment.range.end_line, side);
-        }
-        return;
+        const commentRangesIndex = match[1];
+        const {side, range, hovering} = this.commentRanges[commentRangesIndex];
+        this._updateRangesMap(
+            side, range, hovering, (forLine, start, end, hovering) => {
+              const index = forLine.findIndex(lineRange =>
+                  lineRange.start === start && lineRange.end === end);
+              forLine[index].hovering = hovering;
+            });
       }
 
       // If comments were spliced in or out.
-      match = record.path.match(SPLICE_PATH_PATTERN);
-      if (match) {
-        side = match[1];
-        this._commentMap[side] = this._computeCommentMap(this.comments[side]);
-        this._handleCommentSplice(record.value, side);
+      if (record.path === 'commentRanges.splices') {
+        for (const indexSplice of record.value.indexSplices) {
+          const removed = indexSplice.removed;
+          for (const {side, range, hovering} of removed) {
+            this._updateRangesMap(
+                side, range, hovering, (forLine, start, end) => {
+                  const index = forLine.findIndex(lineRange =>
+                      lineRange.start === start && lineRange.end === end);
+                  forLine.splice(index, 1);
+                });
+          }
+          const added = indexSplice.object.slice(
+              indexSplice.index, indexSplice.index + indexSplice.addedCount);
+          for (const {side, range, hovering} of added) {
+            this._updateRangesMap(
+                side, range, hovering, (forLine, start, end, hovering) => {
+                  forLine.push({start, end, hovering});
+                });
+          }
+        }
       }
     },
 
-    /**
-     * Take a list of comments and return a sparse list mapping line numbers to
-     * partial ranges. Uses an end-character-index of -1 to indicate the end of
-     * the line.
-     * @param {?} commentList The list of comments.
-     *    Getting this param to match closure requirements caused problems.
-     * @return {!Object} The sparse list.
-     */
-    _computeCommentMap(commentList) {
-      const result = {};
-      for (const comment of commentList) {
-        if (!comment.range) { continue; }
-        const range = comment.range;
-        for (let line = range.start_line; line <= range.end_line; line++) {
-          if (!result[line]) { result[line] = []; }
-          result[line].push({
-            comment,
-            start: line === range.start_line ? range.start_character : 0,
-            end: line === range.end_line ? range.end_character : -1,
-          });
-        }
+    _updateRangesMap(side, range, hovering, operation) {
+      const forSide = this._rangesMap[side] || (this._rangesMap[side] = {});
+      for (let line = range.start_line; line <= range.end_line; line++) {
+        const forLine = forSide[line] || (forSide[line] = []);
+        const start = line === range.start_line ? range.start_character : 0;
+        const end = line === range.end_line ? range.end_character : -1;
+        operation(forLine, start, end, hovering);
       }
-      return result;
-    },
-
-    /**
-     * Translate a splice record into range update notifications.
-     */
-    _handleCommentSplice(record, side) {
-      if (!record || !record.indexSplices) { return; }
-
-      for (const splice of record.indexSplices) {
-        const ranges = splice.removed.length ?
-            splice.removed.map(c => { return c.range; }) :
-            [splice.object[splice.index].range];
-        for (const range of ranges) {
-          if (!range) { continue; }
-          this._notifyUpdateRange(range.start_line, range.end_line, side);
-        }
-      }
+      this._notifyUpdateRange(range.start_line, range.end_line, side);
     },
 
     _getRangesForLine(line, side) {
       const lineNum = side === 'left' ? line.beforeNumber : line.afterNumber;
-      const ranges = this.get(['_commentMap', side, lineNum]) || [];
+      const ranges = this.get(['_rangesMap', side, lineNum]) || [];
       return ranges
           .map(range => {
-            range = {
-              start: range.start,
-              end: range.end === -1 ? line.text.length : range.end,
-              hovering: !!range.comment.__hovering,
-            };
+            range.end = range.end === -1 ? line.text.length : range.end;
 
             // Normalize invalid ranges where the start is after the end but the
             // start still makes sense. Set the end to the end of the line.
diff --git a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html
index c541e26..c198ace 100644
--- a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html
@@ -40,62 +40,48 @@
     let sandbox;
 
     setup(() => {
-      const initialComments = {
-        left: [
-          {
-            id: '12345',
-            line: 39,
-            message: 'range comment',
-            range: {
-              end_character: 9,
-              end_line: 39,
-              start_character: 6,
-              start_line: 36,
-            },
-          }, {
-            id: '23456',
-            line: 100,
-            message: 'non range comment',
+      const initialCommentRanges = [
+        {
+          side: 'left',
+          range: {
+            end_character: 9,
+            end_line: 39,
+            start_character: 6,
+            start_line: 36,
           },
-        ],
-        right: [
-          {
-            id: '34567',
-            line: 10,
-            message: 'range comment',
-            range: {
-              end_character: 22,
-              end_line: 12,
-              start_character: 10,
-              start_line: 10,
-            },
-          }, {
-            id: '45678',
-            line: 100,
-            message: 'single line range comment',
-            range: {
-              end_character: 15,
-              end_line: 100,
-              start_character: 5,
-              start_line: 100,
-            },
-          }, {
-            id: '8675309',
-            line: 55,
-            message: 'nonsense range',
-            range: {
-              end_character: 2,
-              end_line: 55,
-              start_character: 32,
-              start_line: 55,
-            },
+        },
+        {
+          side: 'right',
+          range: {
+            end_character: 22,
+            end_line: 12,
+            start_character: 10,
+            start_line: 10,
           },
-        ],
-      };
+        },
+        {
+          side: 'right',
+          range: {
+            end_character: 15,
+            end_line: 100,
+            start_character: 5,
+            start_line: 100,
+          },
+        },
+        {
+          side: 'right',
+          range: {
+            end_character: 2,
+            end_line: 55,
+            start_character: 32,
+            start_line: 55,
+          },
+        },
+      ];
 
       sandbox = sinon.sandbox.create();
       element = fixture('basic');
-      element.comments = initialComments;
+      element.commentRanges = initialCommentRanges;
     });
 
     teardown(() => {
@@ -149,7 +135,7 @@
       test('type=Remove has-comment hovering', () => {
         line.type = GrDiffLine.Type.REMOVE;
         line.beforeNumber = 36;
-        element.set(['comments', 'left', 0, '__hovering'], true);
+        element.set(['commentRanges', 0, 'hovering'], true);
 
         const expectedStart = 6;
         const expectedLength = line.text.length - expectedStart;
@@ -210,29 +196,18 @@
       });
     });
 
-    test('_handleCommentChange overwrite', () => {
-      const handlerSpy = sandbox.spy(element, '_handleCommentChange');
-      const mapSpy = sandbox.spy(element, '_computeCommentMap');
+    test('_handleCommentRangesChange overwrite', () => {
+      element.set('commentRanges', []);
 
-      element.set('comments', {left: [], right: []});
-
-      assert.isTrue(handlerSpy.called);
-      assert.equal(mapSpy.callCount, 2);
-
-      assert.equal(Object.keys(element._commentMap.left).length, 0);
-      assert.equal(Object.keys(element._commentMap.right).length, 0);
+      assert.equal(Object.keys(element._rangesMap.left).length, 0);
+      assert.equal(Object.keys(element._rangesMap.right).length, 0);
     });
 
-    test('_handleCommentChange hovering', () => {
-      const handlerSpy = sandbox.spy(element, '_handleCommentChange');
-      const mapSpy = sandbox.spy(element, '_computeCommentMap');
+    test('_handleCommentRangesChange hovering', () => {
       const notifyStub = sinon.stub();
       element.addListener(notifyStub);
 
-      element.set(['comments', 'right', 0, '__hovering'], true);
-
-      assert.isTrue(handlerSpy.called);
-      assert.isTrue(mapSpy.called);
+      element.set(['commentRanges', 1, 'hovering'], true);
 
       assert.isTrue(notifyStub.called);
       const lastCall = notifyStub.lastCall;
@@ -241,16 +216,11 @@
       assert.equal(lastCall.args[2], 'right');
     });
 
-    test('_handleCommentChange splice out', () => {
-      const handlerSpy = sandbox.spy(element, '_handleCommentChange');
-      const mapSpy = sandbox.spy(element, '_computeCommentMap');
+    test('_handleCommentRangesChange splice out', () => {
       const notifyStub = sinon.stub();
       element.addListener(notifyStub);
 
-      element.splice('comments.right', 0, 1);
-
-      assert.isTrue(handlerSpy.called);
-      assert.isTrue(mapSpy.called);
+      element.splice('commentRanges', 1, 1);
 
       assert.isTrue(notifyStub.called);
       const lastCall = notifyStub.lastCall;
@@ -259,16 +229,12 @@
       assert.equal(lastCall.args[2], 'right');
     });
 
-    test('_handleCommentChange splice in', () => {
-      const handlerSpy = sandbox.spy(element, '_handleCommentChange');
-      const mapSpy = sandbox.spy(element, '_computeCommentMap');
+    test('_handleCommentRangesChange splice in', () => {
       const notifyStub = sinon.stub();
       element.addListener(notifyStub);
 
-      element.splice('comments.left', element.comments.left.length, 0, {
-        id: '56123',
-        line: 250,
-        message: 'new range comment',
+      element.splice('commentRanges', 1, 0, {
+        side: 'left',
         range: {
           end_character: 15,
           end_line: 275,
@@ -277,9 +243,6 @@
         },
       });
 
-      assert.isTrue(handlerSpy.called);
-      assert.isTrue(mapSpy.called);
-
       assert.isTrue(notifyStub.called);
       const lastCall = notifyStub.lastCall;
       assert.equal(lastCall.args[0], 250);
@@ -291,48 +254,48 @@
       // There is only one ranged comment on the left, but it spans ll.36-39.
       const leftKeys = [];
       for (let i = 36; i <= 39; i++) { leftKeys.push('' + i); }
-      assert.deepEqual(Object.keys(element._commentMap.left).sort(),
+      assert.deepEqual(Object.keys(element._rangesMap.left).sort(),
           leftKeys.sort());
 
-      assert.equal(element._commentMap.left[36].length, 1);
-      assert.equal(element._commentMap.left[36][0].start, 6);
-      assert.equal(element._commentMap.left[36][0].end, -1);
+      assert.equal(element._rangesMap.left[36].length, 1);
+      assert.equal(element._rangesMap.left[36][0].start, 6);
+      assert.equal(element._rangesMap.left[36][0].end, -1);
 
-      assert.equal(element._commentMap.left[37].length, 1);
-      assert.equal(element._commentMap.left[37][0].start, 0);
-      assert.equal(element._commentMap.left[37][0].end, -1);
+      assert.equal(element._rangesMap.left[37].length, 1);
+      assert.equal(element._rangesMap.left[37][0].start, 0);
+      assert.equal(element._rangesMap.left[37][0].end, -1);
 
-      assert.equal(element._commentMap.left[38].length, 1);
-      assert.equal(element._commentMap.left[38][0].start, 0);
-      assert.equal(element._commentMap.left[38][0].end, -1);
+      assert.equal(element._rangesMap.left[38].length, 1);
+      assert.equal(element._rangesMap.left[38][0].start, 0);
+      assert.equal(element._rangesMap.left[38][0].end, -1);
 
-      assert.equal(element._commentMap.left[39].length, 1);
-      assert.equal(element._commentMap.left[39][0].start, 0);
-      assert.equal(element._commentMap.left[39][0].end, 9);
+      assert.equal(element._rangesMap.left[39].length, 1);
+      assert.equal(element._rangesMap.left[39][0].start, 0);
+      assert.equal(element._rangesMap.left[39][0].end, 9);
 
       // The right has two ranged comments, one spanning ll.10-12 and the other
       // on line 100.
       const rightKeys = [];
       for (let i = 10; i <= 12; i++) { rightKeys.push('' + i); }
       rightKeys.push('55', '100');
-      assert.deepEqual(Object.keys(element._commentMap.right).sort(),
+      assert.deepEqual(Object.keys(element._rangesMap.right).sort(),
           rightKeys.sort());
 
-      assert.equal(element._commentMap.right[10].length, 1);
-      assert.equal(element._commentMap.right[10][0].start, 10);
-      assert.equal(element._commentMap.right[10][0].end, -1);
+      assert.equal(element._rangesMap.right[10].length, 1);
+      assert.equal(element._rangesMap.right[10][0].start, 10);
+      assert.equal(element._rangesMap.right[10][0].end, -1);
 
-      assert.equal(element._commentMap.right[11].length, 1);
-      assert.equal(element._commentMap.right[11][0].start, 0);
-      assert.equal(element._commentMap.right[11][0].end, -1);
+      assert.equal(element._rangesMap.right[11].length, 1);
+      assert.equal(element._rangesMap.right[11][0].start, 0);
+      assert.equal(element._rangesMap.right[11][0].end, -1);
 
-      assert.equal(element._commentMap.right[12].length, 1);
-      assert.equal(element._commentMap.right[12][0].start, 0);
-      assert.equal(element._commentMap.right[12][0].end, 22);
+      assert.equal(element._rangesMap.right[12].length, 1);
+      assert.equal(element._rangesMap.right[12][0].start, 0);
+      assert.equal(element._rangesMap.right[12][0].end, 22);
 
-      assert.equal(element._commentMap.right[100].length, 1);
-      assert.equal(element._commentMap.right[100][0].start, 5);
-      assert.equal(element._commentMap.right[100][0].end, 15);
+      assert.equal(element._rangesMap.right[100].length, 1);
+      assert.equal(element._rangesMap.right[100][0].start, 5);
+      assert.equal(element._rangesMap.right[100][0].end, 15);
     });
 
     test('_getRangesForLine normalizes invalid ranges', () => {