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<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
<title>gr-diff-highlight</title>

<script src="../../../bower_components/webcomponentsjs/webcomponents.min.js"></script>
<script src="../../../bower_components/web-component-tester/browser.js"></script>

<link rel="import" href="../../../bower_components/iron-test-helpers/iron-test-helpers.html">
<link rel="import" href="gr-diff-highlight.html">

<test-fixture id="basic">
  <template>
    <gr-diff-highlight>
      <table id="diffTable">

        <tbody class="section both">
          <tr class="diff-row side-by-side" left-type="both" right-type="both">
            <td class="left lineNum" data-value="138">138</td>
            <td class="content both darkHighlight">[14] Nam cum ad me in Cumanum salutandi causa uterque venisset,</td>
            <td class="right lineNum" data-value="119">119</td>
            <td class="content both darkHighlight">[14] Nam cum ad me in Cumanum salutandi causa uterque venisset,</td>
          </tr>
        </tbody>

        <tbody class="section delta">
          <tr class="diff-row side-by-side" left-type="remove" right-type="add">
            <td class="left lineNum" data-value="140">140</td>
            <!-- Next tag is formatted to eliminate zero-length text nodes. -->
            <td class="content remove lightHighlight">na💢ti <hl class="foo">te, inquit</hl>, sumus <hl class="bar">aliquando</hl> otiosum, <hl>certe</hl> a <hl><span class="tab withIndicator" style="tab-size:8;"></span></hl>udiam, <hl>quid</hl> sit, <span class="tab withIndicator" style="tab-size:8;"></span>quod <hl>Epicurum</hl><gr-diff-comment-thread>
                [Yet another random diff thread content here]
              </gr-diff-comment-thread></td>
            <td class="right lineNum" data-value="120">120</td>
            <!-- Next tag is formatted to eliminate zero-length text nodes. -->
            <td class="content add lightHighlight">nacti , <hl>,</hl> sumus <hl><span class="tab withIndicator" style="tab-size:8;"></span></hl> otiosum,  <span class="tab withIndicator" style="tab-size:8;"></span> audiam,  sit, quod</td>
          </tr>
        </tbody>

        <tbody class="section both">
          <tr class="diff-row side-by-side" left-type="both" right-type="both">
            <td class="left lineNum" data-value="141"></td>
            <td class="content both darkHighlight">nam et<hl><span class="tab withIndicator" style="tab-size:8;">	</span></hl>complectitur<span class="tab withIndicator" style="tab-size:8;">	</span>verbis, quod vult, et dicit plane, quod intellegam;</td>
            <td class="right lineNum" data-value="130"></td>
            <td class="content both darkHighlight">nam et complectitur verbis, quod vult, et dicit plane, quod intellegam;</td>
          </tr>
        </tbody>

        <tbody class="section contextControl">
          <tr class="diff-row side-by-side" left-type="contextControl" right-type="contextControl">
            <td class="left contextLineNum" data-value="@@"></td>
            <td>
              <gr-button>+10↑</gr-button>
              -
              <gr-button>Show 21 common lines</gr-button>
              -
              <gr-button>+10↓</gr-button>
            </td>
            <td class="right contextLineNum" data-value="@@"></td>
            <td>
              <gr-button>+10↑</gr-button>
              -
              <gr-button>Show 21 common lines</gr-button>
              -
              <gr-button>+10↓</gr-button>
            </td>
          </tr>
        </tbody>

        <tbody class="section delta">
          <tr class="diff-row side-by-side" left-type="blank" right-type="add">
            <td class="left"></td>
            <td class="blank darkHighlight"></td>
            <td class="right lineNum" data-value="146"></td>
            <td class="content add darkHighlight">[17] Quid igitur est? inquit; audire enim cupio, quid non probes. Principio, inquam,</td>
          </tr>
        </tbody>

        <tbody class="section both">
          <tr class="diff-row side-by-side" left-type="both" right-type="both">
            <td class="left lineNum" data-value="165"></td>
            <td class="content both darkHighlight">in physicis, quibus maxime gloriatur, primum totus est alienus. Democritea dicit</td>
            <td class="right lineNum" data-value="147"></td>
            <td class="content both darkHighlight">in physicis, <hl><span class="tab withIndicator" style="tab-size:8;">	</span></hl> quibus maxime gloriatur, primum totus est alienus. Democritea dicit</td>
          </tr>
        </tbody>

      </table>
    </gr-diff-highlight>
  </template>
</test-fixture>

<test-fixture id="highlighted">
  <template>
    <div>
      <hl class="rangeHighlight">foo</hl>
      bar
      <hl class="rangeHighlight">baz</hl>
    </div>
  </template>
</test-fixture>

<script>
  suite('gr-diff-highlight', function() {
    var element;
    var sandbox;

    setup(function() {
      sandbox = sinon.sandbox.create();
      element = fixture('basic');
    });

    teardown(function() {
      sandbox.restore();
    });

    test('_enabledListeners', function() {
      var listeners = element._enabledListeners;
      for (var eventName in listeners) {
        sandbox.stub(element, listeners[eventName]);
      }
      // Enable all the listeners.
      element.enabled = true;
      for (var eventName in listeners) {
        var methodName = listeners[eventName];
        var stub = element[methodName];
        element.fire(eventName);
        assert.isTrue(stub.called);
        stub.reset();
      }
      // Disable all the listeners.
      element.enabled = false;
      for (var eventName in listeners) {
        var methodName = listeners[eventName];
        var stub = element[methodName];
        element.fire(eventName);
        assert.isFalse(stub.called);
      }
    });

    test('does not listen to selectionchange when disabled', function() {
      sandbox.stub(element, '_handleSelection');
      sandbox.stub(element, '_removeActionBox');
      element.enabled = false;
      document.dispatchEvent(new CustomEvent('selectionchange'));
      element.flushDebouncer('selectionChange');
      assert.isFalse(element._handleSelection.called);
      element.flushDebouncer('removeActionBox');
      assert.isFalse(element._removeActionBox.called);
    });

    test('listens to selectionchange when enabled', function() {
      sandbox.stub(element, '_handleSelection');
      sandbox.stub(element, '_removeActionBox');
      element.enabled = true;
      document.dispatchEvent(new CustomEvent('selectionchange'));
      element.flushDebouncer('selectionChange');
      assert.isTrue(element._handleSelection.called);
      element.flushDebouncer('removeActionBox');
      assert.isTrue(element._removeActionBox.called);
    });

    suite('comment events', function() {
      var builder;

      setup(function() {
        builder = {
          getContentsByLineRange: sandbox.stub().returns([]),
          getLineElByChild: sandbox.stub().returns({}),
          getSideByLineEl: sandbox.stub().returns('other-side'),
          renderLineRange: sandbox.stub(),
        };
        element._cachedDiffBuilder = builder;
        element.enabled = true;
      });

      test('ignores thread discard for line comment', function(done) {
        element.fire('thread-discard', {lastComment: {}});
        flush(function() {
          assert.isFalse(builder.renderLineRange.called);
          done();
        });
      });

      test('ignores comment discard for line comment', function(done) {
        element.fire('comment-discard', {comment: {}});
        flush(function() {
          assert.isFalse(builder.renderLineRange.called);
          done();
        });
      });

      test('renders lines in comment range on thread discard', function(done) {
        element.fire('thread-discard', {
          lastComment: {
            range: {
              start_line: 10,
              end_line: 24,
            },
          },
        });
        flush(function() {
          assert.isTrue(
              builder.renderLineRange.calledWithExactly(10, 24, 'other-side'));
          done();
        });
      });

      test('renders lines in comment range on comment discard', function(done) {
        element.fire('comment-discard', {
          comment: {
            range: {
              start_line: 10,
              end_line: 24,
            },
          },
        });
        flush(function() {
          assert.isTrue(
              builder.renderLineRange.calledWithExactly(10, 24, 'other-side'));
          done();
        });
      });

      test('comment-mouse-over from line comments is ignored', function() {
        sandbox.stub(element, '_applyRangedHighlight');
        element.fire('comment-mouse-over', {comment: {}});
        assert.isFalse(element._applyRangedHighlight.called);
      });

      test('comment-mouse-out from line comments is ignored', function() {
        element.fire('comment-mouse-over', {comment: {}});
        assert.isFalse(builder.getContentsByLineRange.called);
      });

      test('on comment-mouse-out highlight classes are removed', function() {
        var testEl = fixture('highlighted');
        builder.getContentsByLineRange.returns([testEl]);
        element.fire('comment-mouse-out', {
          comment: {
            range: {
              start_line: 3,
              start_character: 14,
              end_line: 10,
              end_character: 24,
            }
          }});
        assert.isTrue(builder.getContentsByLineRange.calledWithExactly(
            3, 10, 'other-side'));
        assert.equal(0, testEl.querySelectorAll('.rangeHighlight').length);
        assert.equal(2, testEl.querySelectorAll('.range').length);
      });

      test('on comment-mouse-over range is highlighted', function() {
        sandbox.stub(element, '_applyRangedHighlight');
        element.fire('comment-mouse-over', {
          comment: {
            range: {
              start_line: 3,
              start_character: 14,
              end_line: 10,
              end_character: 24,
            },
          }});
        assert.isTrue(element._applyRangedHighlight.calledWithExactly(
            'rangeHighlight', 3, 14, 10, 24, 'other-side'));
      });

      test('on create-comment range is highlighted', function() {
        sandbox.stub(element, '_applyRangedHighlight');
        element.fire('create-comment', {
          range: {
            startLine: 3,
            startChar: 14,
            endLine: 10,
            endChar: 24,
          },
          side: 'some-side',
        });
        assert.isTrue(element._applyRangedHighlight.calledWithExactly(
            'range', 3, 14, 10, 24, 'some-side'));
      });

      test('on create-comment action box is removed', function() {
        sandbox.stub(element, '_applyRangedHighlight');
        sandbox.stub(element, '_removeActionBox');
        element.fire('create-comment', {
          comment: {
            range: {},
          },
        });
        assert.isTrue(element._removeActionBox.called);
      });
    });

    test('apply multiline highlight', function() {
      var diff = element.querySelector('#diffTable');
      var startContent =
          diff.querySelector('.left.lineNum[data-value="138"] ~ .content');
      var betweenContent =
          diff.querySelector('.left.lineNum[data-value="140"] ~ .content');
      var endContent =
          diff.querySelector('.left.lineNum[data-value="141"] ~ .content');
      var commentThread =
          diff.querySelector('gr-diff-comment-thread');
      var builder = {
        getCommentThreadByContentEl: sandbox.stub().returns(commentThread),
        getContentByLine: sandbox.stub().returns({}),
        getContentsByLineRange: sandbox.stub().returns([betweenContent]),
        getLineElByChild: sandbox.stub().returns(
            {getAttribute: sandbox.stub()}),
      };
      element._cachedDiffBuilder = builder;
      element.enabled = true;
      builder.getContentByLine.withArgs(138, 'left').returns(
          startContent);
      builder.getContentByLine.withArgs(141, 'left').returns(
          endContent);
      element._applyRangedHighlight('some', 138, 4, 141, 28, 'left');
      assert.instanceOf(startContent.childNodes[0], Text);
      assert.equal(startContent.childNodes[0].textContent, '[14]');
      assert.instanceOf(startContent.childNodes[1], Element);
      assert.equal(startContent.childNodes[1].textContent,
          ' Nam cum ad me in Cumanum salutandi causa uterque venisset,');
      assert.equal(startContent.childNodes[1].tagName, 'HL');
      assert.equal(startContent.childNodes[1].className, 'some');

      assert.instanceOf(betweenContent.firstChild, Element);
      assert.equal(betweenContent.firstChild.tagName, 'HL');
      assert.equal(betweenContent.firstChild.className, 'some');
      assert.equal(betweenContent.childNodes.length, 2);
      assert.equal(betweenContent.firstChild.childNodes.length, 1);
      assert.equal(betweenContent.firstChild.textContent,
          'na💢ti te, inquit, sumus aliquando otiosum, certe a udiam, ' +
          'quid sit, quod Epicurum');

      assert.isNull(diff.querySelector('.right + .content .some'),
          'Highlight should be applied only to the left side content.');

      assert.strictEqual(betweenContent.querySelector('gr-diff-comment-thread'),
          commentThread, 'Comment threads should be preserved.');

      assert.instanceOf(endContent.childNodes[0], Element);
      assert.equal(endContent.childNodes[0].textContent,
          'nam et\tcomplectitur\tverbis, ');
      assert.equal(endContent.childNodes[0].tagName, 'HL');
      assert.equal(endContent.childNodes[0].className, 'some');
      assert.instanceOf(endContent.childNodes[1], Text);
      assert.equal(endContent.childNodes[1].textContent,
          'quod vult, et dicit plane, quod intellegam;');
      var endHl = endContent.querySelector('hl.some');
      assert.equal(endHl.childNodes.length, 5);
      var tabs = endHl.querySelectorAll('span.tab');
      assert.equal(tabs.length, 2);
      assert.equal(tabs[0].previousSibling.textContent, 'nam et');
      assert.equal(tabs[1].previousSibling.textContent, 'complectitur');
      assert.equal(tabs[1].nextSibling.textContent, 'verbis, ');
    });

    test('multiline highlight w/ start at end of 1st line', function() {
      var diff = element.querySelector('#diffTable');
      var startContent =
          diff.querySelector('.left.lineNum[data-value="138"] ~ .content');
      var betweenContent =
          diff.querySelector('.left.lineNum[data-value="140"] ~ .content');
      var endContent =
          diff.querySelector('.left.lineNum[data-value="141"] ~ .content');
      var commentThread =
          diff.querySelector('gr-diff-comment-thread');
      var builder = {
        getCommentThreadByContentEl: sandbox.stub().returns(commentThread),
        getContentByLine: sandbox.stub().returns({}),
        getContentsByLineRange: sandbox.stub().returns([betweenContent]),
        getLineElByChild: sandbox.stub().returns(
            {getAttribute: sandbox.stub()}),
      };
      element._cachedDiffBuilder = builder;
      element.enabled = true;
      builder.getContentByLine.withArgs(138, 'left').returns(
          startContent);
      builder.getContentByLine.withArgs(141, 'left').returns(
          endContent);

      var expectedStartContentNodes = startContent.childNodes.length;

      // The following should not cause an error.
      element._applyRangedHighlight(
          'some', 138, startContent.textContent.length, 141, 28, 'left');

      assert.equal(startContent.childNodes.length, expectedStartContentNodes,
          'Should not add a highlight to the start content');
    });

    suite('single line ranges', function() {
      var diff;
      var content;
      var commentThread;
      var builder;

      setup(function() {
        diff = element.querySelector('#diffTable');
        content =
            diff.querySelector('.left.lineNum[data-value="140"] ~ .content');
        commentThread = diff.querySelector('gr-diff-comment-thread');
        builder = {
          getCommentThreadByContentEl: sandbox.stub().returns(commentThread),
          getContentByLine: sandbox.stub().returns(content),
          getContentsByLineRange: sandbox.stub().returns([]),
          getLineElByChild: sandbox.stub().returns(
              {getAttribute: sandbox.stub()}),
        };
        element._cachedDiffBuilder = builder;
        element.enabled = true;
      });

      test('whole line range', function() {
        element._applyRangedHighlight('some', 140, 0, 140, 81, 'left');
        assert.instanceOf(content.firstChild, Element);
        assert.equal(content.firstChild.tagName, 'HL');
        assert.equal(content.firstChild.className, 'some');
        assert.equal(content.childNodes.length, 2);
        assert.equal(content.firstChild.childNodes.length, 5);
        assert.equal(content.firstChild.textContent,
            'na💢ti te, inquit, sumus aliquando otiosum, certe a udiam, ' +
            'quid sit, quod Epicurum');
        var tabs = content.querySelectorAll('span.tab');
        assert.equal(tabs.length, 2);
        assert.strictEqual(tabs[1].previousSibling, tabs[0].nextSibling);
        assert.equal(tabs[0].previousSibling.textContent,
            'na💢ti te, inquit, sumus aliquando otiosum, certe a ');
        assert.equal(tabs[1].previousSibling.textContent,
            'udiam, quid sit, ');
        assert.equal(tabs[1].nextSibling.textContent, 'quod Epicurum');
      });

      test('merging multiple other hls', function() {
        element._applyRangedHighlight('some', 140, 1, 140, 80, 'left');
        assert.instanceOf(content.firstChild, Text);
        assert.equal(content.childNodes.length, 4);
        var hl = content.querySelector('hl.some');
        assert.strictEqual(content.firstChild, hl.previousSibling);
        assert.equal(hl.childNodes.length, 5);
        assert.equal(content.querySelectorAll('span.tab').length, 2);
        assert.equal(hl.textContent,
            'a💢ti te, inquit, sumus aliquando otiosum, certe a udiam, ' +
            'quid sit, quod Epicuru');
      });

      test('hl inside Text node', function() {
        // Before: na💢ti
        //  After: n<hl class="some">a💢t</hl>i
        element._applyRangedHighlight('some', 140, 1, 140, 4, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.outerHTML, '<hl class="some">a💢t</hl>');
      });

      test('hl ending over different hl', function() {
        // Before: na💢ti <hl>te, inquit</hl>,
        //  After: na💢<hl class="some">ti te</hl><hl class="foo">, inquit</hl>,
        element._applyRangedHighlight('some', 140, 3, 140, 8, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.outerHTML, '<hl class="some">ti te</hl>');
        assert.equal(hl.nextSibling.outerHTML,
            '<hl class="foo">, inquit</hl>');
      });

      test('hl starting inside different hl', function() {
        // Before: na💢ti <hl>te, inquit</hl>, sumus
        //  After: na💢ti <hl class="foo">te, in</hl><hl class="some">quit, ...
        element._applyRangedHighlight('some', 140, 12, 140, 21, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.textContent, 'quit, sum');
        assert.equal(
            hl.previousSibling.outerHTML, '<hl class="foo">te, in</hl>');
      });

      test('hl inside different hl', function() {
        // Before: na💢ti <hl class="foo">te, inquit</hl>, sumus
        //  After: <hl class="foo">t</hl><hl="some">e, i</hl><hl class="foo">n..
        element._applyRangedHighlight('some', 140, 7, 140, 12, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.textContent, 'e, in');
        assert.equal(hl.previousSibling.outerHTML, '<hl class="foo">t</hl>');
        assert.equal(hl.nextSibling.outerHTML, '<hl class="foo">quit</hl>');
      });

      test('hl starts and ends in different hls', function() {
        element._applyRangedHighlight('some', 140, 8, 140, 27, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.textContent, ', inquit, sumus ali');
        assert.equal(hl.previousSibling.outerHTML, '<hl class="foo">te</hl>');
        assert.equal(hl.nextSibling.outerHTML, '<hl class="bar">quando</hl>');
      });

      test('hl over different hl', function() {
        element._applyRangedHighlight('some', 140, 2, 140, 21, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.outerHTML, '<hl class="some">💢ti te, inquit, sum</hl>');
        assert.notOk(content.querySelector('.foo'));
      });

      test('hl starting and ending in boundaries', function() {
        element._applyRangedHighlight('some', 140, 6, 140, 33, 'left');
        var hl = content.querySelector('hl.some');
        assert.equal(hl.textContent, 'te, inquit, sumus aliquando');
        assert.notOk(content.querySelector('.bar'));
      });

      test('overlapping hls', function() {
        element._applyRangedHighlight('some', 140, 1, 140, 3, 'left');
        element._applyRangedHighlight('some', 140, 2, 140, 4, 'left');
        assert.equal(content.querySelectorAll('hl.some').length, 1);
        var hl = content.querySelector('hl.some');
        assert.equal(hl.outerHTML, '<hl class="some">a💢t</hl>');
      });

      test('growing hl right including another hl', function() {
        element._applyRangedHighlight('some', 140, 1, 140, 4, 'left');
        element._applyRangedHighlight('some', 140, 3, 140, 10, 'left');
        assert.equal(content.querySelectorAll('hl.some').length, 1);
        var hl = content.querySelector('hl.some');
        assert.equal(hl.outerHTML, '<hl class="some">a💢ti te, </hl>');
        assert.equal(hl.nextSibling.outerHTML, '<hl class="foo">inquit</hl>');
      });

      test('growing hl left to start of line', function() {
        element._applyRangedHighlight('some', 140, 2, 140, 5, 'left');
        element._applyRangedHighlight('some', 140, 0, 140, 3, 'left');
        assert.equal(content.querySelectorAll('hl.some').length, 1);
        var hl = content.querySelector('hl.some');
        assert.equal(hl.outerHTML, '<hl class="some">na💢ti</hl>');
        assert.strictEqual(content.firstChild, hl);
      });

      test('splitting hl containing a tab', function() {
        element._applyRangedHighlight('some', 140, 63, 140, 72, 'left');
        assert.equal(content.querySelector('hl.some').textContent, 'sit, quod');
        element._applyRangedHighlight('another', 140, 66, 140, 81, 'left');
        assert.equal(content.querySelector('hl.another').textContent,
            ', quod Epicurum');
      });
    });

    test('_applyAllHighlights', function() {
      element.comments = {
        left: [
          {
            range: {
              start_line: 3,
              start_character: 14,
              end_line: 10,
              end_character: 24,
            },
          },
        ],
        right: [
          {
            range: {
              start_line: 320,
              start_character: 200,
              end_line: 1024,
              end_character: 768,
            },
          },
        ],
      };
      sandbox.stub(element, '_applyRangedHighlight');
      element._applyAllHighlights();
      sinon.assert.calledWith(element._applyRangedHighlight,
          'range', 3, 14, 10, 24, 'left');
      sinon.assert.calledWith(element._applyRangedHighlight,
          'range', 320, 200, 1024, 768, 'right');
    });

    test('apply comment ranges on render', function() {
      element.enabled = true;
      sandbox.stub(element, '_applyAllHighlights');
      element.fire('render');
      assert.isTrue(element._applyAllHighlights.called);
    });

    test('apply comment ranges on context expand', function() {
      element.enabled = true;
      sandbox.stub(element, '_applyAllHighlights');
      element.fire('show-context');
      assert.isTrue(element._applyAllHighlights.called);
    });

    test('ignores render when disabled', function() {
      element.enabled = false;
      sandbox.stub(element, '_applyAllHighlights');
      element.fire('render');
      assert.isFalse(element._applyAllHighlights.called);
    });

    test('ignores context expand when disabled', function() {
      element.enabled = false;
      sandbox.stub(element, '_applyAllHighlights');
      element.fire('show-context');
      assert.isFalse(element._applyAllHighlights.called);
    });

    suite('selection', function() {
      var diff;
      var builder;
      var contentStubs;

      var stubContent = function(line, side, opt_child) {
        var content = diff.querySelector(
            '.' + side + '.lineNum[data-value="' + line + '"] ~ .content');
        var lineEl = diff.querySelector(
            '.' + side + '.lineNum[data-value="' + line + '"]');
        contentStubs.push({
          lineEl: lineEl,
          content: content,
        });
        builder.getContentByLineEl.withArgs(lineEl).returns(content);
        builder.getLineNumberByChild.withArgs(lineEl).returns(line);
        builder.getContentByLine.withArgs(line, side).returns(content);
        builder.getSideByLineEl.withArgs(lineEl).returns(side);
        return content;
      };

      var emulateSelection = function(
          startNode, startOffset, endNode, endOffset) {
        var selection = window.getSelection();
        var range = document.createRange();
        range.setStart(startNode, startOffset);
        range.setEnd(endNode, endOffset);
        selection.addRange(range);
        element._handleSelection();
      };

      var getActionRange = function() {
        return Polymer.dom(element.root).querySelector(
            'gr-selection-action-box').range;
      };

      var getActionSide = function() {
        return Polymer.dom(element.root).querySelector(
            'gr-selection-action-box').side;
      };

      var getLineElByChild = function(node) {
        var stubs = contentStubs.find(function(stub) {
          return stub.content.contains(node);
        });
        return stubs && stubs.lineEl;
      };

      setup(function() {
        contentStubs = [];
        stub('gr-selection-action-box', {
          placeAbove: sandbox.stub(),
        });
        diff = element.querySelector('#diffTable');
        builder = {
          getContentByLine: sandbox.stub(),
          getContentByLineEl: sandbox.stub(),
          getLineElByChild: getLineElByChild,
          getLineNumberByChild: sandbox.stub(),
          getSideByLineEl: sandbox.stub(),
        };
        element._cachedDiffBuilder = builder;
        element.enabled = true;
      });

      teardown(function() {
        contentStubs = null;
        window.getSelection().removeAllRanges();
      });

      test('single line', function() {
        var content = stubContent(138, 'left');
        emulateSelection(content.firstChild, 5, content.firstChild, 12);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 138,
          startChar: 5,
          endLine: 138,
          endChar: 12,
        });
        assert.equal(getActionSide(), 'left');
      });

      test('multiline', function() {
        var startContent = stubContent(119, 'right');
        var endContent = stubContent(120, 'right');
        emulateSelection(
            startContent.firstChild, 10, endContent.lastChild, 7);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 119,
          startChar: 10,
          endLine: 120,
          endChar: 34,
        });
        assert.equal(getActionSide(), 'right');
      });

      test('multiline grow end highlight over tabs', function() {
        var startContent = stubContent(119, 'right');
        var endContent = stubContent(120, 'right');
        emulateSelection(startContent.firstChild, 10, endContent.firstChild, 2);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 119,
          startChar: 10,
          endLine: 120,
          endChar: 2,
        });
        assert.equal(getActionSide(), 'right');
      });

      test('collapsed', function() {
        var content = stubContent(138, 'left');
        emulateSelection(content.firstChild, 5, content.firstChild, 5);
        assert.isOk(window.getSelection().getRangeAt(0).startContainer);
        assert.isFalse(element.isRangeSelected());
      });

      test('starts inside hl', function() {
        var content = stubContent(140, 'left');
        var hl = content.querySelector('.foo');
        emulateSelection(hl.firstChild, 2, hl.nextSibling, 7);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 8,
          endLine: 140,
          endChar: 23,
        });
        assert.equal(getActionSide(), 'left');
      });

      test('ends inside hl', function() {
        var content = stubContent(140, 'left');
        var hl = content.querySelector('.bar');
        emulateSelection(hl.previousSibling, 2, hl.firstChild, 3);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 18,
          endLine: 140,
          endChar: 27,
        });
      });

      test('multiple hl', function() {
        var content = stubContent(140, 'left');
        var hl = content.querySelectorAll('hl')[4];
        emulateSelection(content.firstChild, 2, hl.firstChild, 2);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 2,
          endLine: 140,
          endChar: 60,
        });
        assert.equal(getActionSide(), 'left');
      });

      test('starts outside of diff', function() {
        var content = stubContent(140, 'left');
        emulateSelection(content.previousElementSibling.firstChild, 2,
            content.firstChild, 2);
        assert.isFalse(element.isRangeSelected());
      });

      test('ends outside of diff', function() {
        var content = stubContent(140, 'left');
        emulateSelection(content.nextElementSibling.firstChild, 2,
            content.firstChild, 2);
        assert.isFalse(element.isRangeSelected());
      });

      test('starts and ends on different sides', function() {
        var startContent = stubContent(140, 'left');
        var endContent = stubContent(130, 'right');
        emulateSelection(startContent.firstChild, 2, endContent.firstChild, 2);
        assert.isFalse(element.isRangeSelected());
      });

      test('starts in comment thread element', function() {
        var startContent = stubContent(140, 'left');
        var comment = startContent.querySelector('gr-diff-comment-thread');
        var endContent = stubContent(141, 'left');
        emulateSelection(comment.firstChild, 2, endContent.firstChild, 4);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 81,
          endLine: 141,
          endChar: 4,
        });
        assert.equal(getActionSide(), 'left');
      });

      test('ends in comment thread element', function() {
        var content = stubContent(140, 'left');
        var comment = content.querySelector('gr-diff-comment-thread');
        emulateSelection(content.firstChild, 4, comment.firstChild, 1);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 4,
          endLine: 140,
          endChar: 81,
        });
        assert.equal(getActionSide(), 'left');
      });

      test('starts in context element', function() {
        var contextControl = diff.querySelector('.contextControl');
        var content = stubContent(146, 'right');
        emulateSelection(contextControl, 0, content.firstChild, 7);
        // TODO (viktard): Select nearest line.
        assert.isFalse(element.isRangeSelected());
      });

      test('ends in context element', function() {
        var contextControl = diff.querySelector('.contextControl');
        var content = stubContent(141, 'left');
        emulateSelection(content.firstChild, 2, contextControl, 0);
        // TODO (viktard): Select nearest line.
        assert.isFalse(element.isRangeSelected());
      });

      test('selection containing context element', function() {
        var startContent = stubContent(130, 'right');
        var endContent = stubContent(146, 'right');
        emulateSelection(startContent.firstChild, 3, endContent.firstChild, 14);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 130,
          startChar: 3,
          endLine: 146,
          endChar: 14,
        });
        assert.equal(getActionSide(), 'right');
      });

      test('ends at a tab', function() {
        var content = stubContent(140, 'left');
        emulateSelection(
            content.firstChild, 1, content.querySelector('span'), 0);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 1,
          endLine: 140,
          endChar: 51,
        });
        assert.equal(getActionSide(), 'left');
      });

      test('starts at a tab', function() {
        var content = stubContent(140, 'left');
        emulateSelection(
            content.querySelectorAll('hl')[3], 0,
            content.querySelectorAll('span')[1], 0);
        assert.isTrue(element.isRangeSelected());
        assert.deepEqual(getActionRange(), {
          startLine: 140,
          startChar: 51,
          endLine: 140,
          endChar: 68,
        });
        assert.equal(getActionSide(), 'left');
      });

      // TODO (viktard): Selection starts in line number.
      // TODO (viktard): Empty lines in selection start.
      // TODO (viktard): Empty lines in selection end.
      // TODO (viktard): Only empty lines selected.
      // TODO (viktard): Unified mode.
    });
  });
</script>