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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-builder</title>

<script src="../../../bower_components/webcomponentsjs/webcomponents-lite.min.js"></script>
<script src="../../../bower_components/web-component-tester/browser.js"></script>
<link rel="import" href="../../../test/common-test-setup.html"/>
<script src="../../../scripts/util.js"></script>
<script src="../gr-diff/gr-diff-line.js"></script>
<script src="../gr-diff/gr-diff-group.js"></script>
<script src="../gr-diff-highlight/gr-annotation.js"></script>
<script src="gr-diff-builder.js"></script>

<link rel="import" href="../../shared/gr-rest-api-interface/mock-diff-response_test.html">
<link rel="import" href="gr-diff-builder.html">

<script>void(0);</script>

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

<test-fixture id="div-with-text">
  <template>
    <div>Lorem ipsum dolor sit amet, suspendisse inceptos vehicula</div>
  </template>
</test-fixture>

<test-fixture id="mock-diff">
  <template>
    <gr-diff-builder view-mode="SIDE_BY_SIDE">
      <table id="diffTable"></table>
    </gr-diff-builder>
  </template>
</test-fixture>

<script>
  suite('gr-diff-builder tests', () => {
    let prefs;
    let element;
    let builder;
    let sandbox;
    const LINE_FEED_HTML = '<span class="style-scope gr-diff br"></span>';

    setup(() => {
      sandbox = sinon.sandbox.create();
      element = fixture('basic');
      stub('gr-rest-api-interface', {
        getLoggedIn() { return Promise.resolve(false); },
        getProjectConfig() { return Promise.resolve({}); },
      });
      prefs = {
        line_length: 10,
        show_tabs: true,
        tab_size: 4,
      };
      builder = new GrDiffBuilder({content: []}, [], prefs);
    });

    teardown(() => { sandbox.restore(); });

    test('filterThreadElsForLocation with no threads', () => {
      const line = {beforeNumber: 3, afterNumber: 5};

      const threads = [];
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threads, line), []);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threads, line,
          Gerrit.DiffSide.LEFT), []);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threads, line,
          Gerrit.DiffSide.RIGHT), []);
    });

    test('filterThreadElsForLocation for line comments', () => {
      const line = {beforeNumber: 3, afterNumber: 5};

      const l3 = document.createElement('div');
      l3.setAttribute('line-num', 3);
      l3.setAttribute('comment-side', 'left');

      const l5 = document.createElement('div');
      l5.setAttribute('line-num', 5);
      l5.setAttribute('comment-side', 'left');

      const r3 = document.createElement('div');
      r3.setAttribute('line-num', 3);
      r3.setAttribute('comment-side', 'right');

      const r5 = document.createElement('div');
      r5.setAttribute('line-num', 5);
      r5.setAttribute('comment-side', 'right');

      const threadEls = [l3, l5, r3, r5];
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line),
          [l3, r5]);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line,
          Gerrit.DiffSide.LEFT), [l3]);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line,
          Gerrit.DiffSide.RIGHT), [r5]);
    });

    test('filterThreadElsForLocation for file comments', () => {
      const line = {beforeNumber: 'FILE', afterNumber: 'FILE'};

      const l = document.createElement('div');
      l.setAttribute('comment-side', 'left');

      const r = document.createElement('div');
      r.setAttribute('comment-side', 'right');

      const threadEls = [l, r];
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line),
          [l, r]);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line,
          Gerrit.DiffSide.BOTH), [l, r]);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line,
          Gerrit.DiffSide.LEFT), [l]);
      assert.deepEqual(Gerrit.filterThreadElsForLocation(threadEls, line,
          Gerrit.DiffSide.RIGHT), [r]);
    });

    test('_createElement classStr applies all classes', () => {
      const node = builder._createElement('div', 'test classes');
      assert.isTrue(node.classList.contains('gr-diff'));
      assert.isTrue(node.classList.contains('test'));
      assert.isTrue(node.classList.contains('classes'));
    });

    test('context control buttons', () => {
      const section = {};
      const line = {contextGroup: {lines: []}};

      // Create 10 lines.
      for (let i = 0; i < 10; i++) {
        line.contextGroup.lines.push('lorem upsum');
      }

      // Does not include +10 buttons when there are fewer than 11 lines.
      let td = builder._createContextControl(section, line);
      let buttons = td.querySelectorAll('gr-button.showContext');

      assert.equal(buttons.length, 1);
      assert.equal(Polymer.dom(buttons[0]).textContent, 'Show 10 common lines');

      // Add another line.
      line.contextGroup.lines.push('lorem upsum');

      // Includes +10 buttons when there are at least 11 lines.
      td = builder._createContextControl(section, line);
      buttons = td.querySelectorAll('gr-button.showContext');

      assert.equal(buttons.length, 3);
      assert.equal(Polymer.dom(buttons[0]).textContent, '+10↑');
      assert.equal(Polymer.dom(buttons[1]).textContent, 'Show 11 common lines');
      assert.equal(Polymer.dom(buttons[2]).textContent, '+10↓');
    });

    test('newlines 1', () => {
      let text = 'abcdef';

      assert.equal(builder._formatText(text, 4, 10).innerHTML, text);
      text = 'a'.repeat(20);
      assert.equal(builder._formatText(text, 4, 10).innerHTML,
          'a'.repeat(10) +
          LINE_FEED_HTML +
          'a'.repeat(10));
    });

    test('newlines 2', () => {
      const text = '<span class="thumbsup">👍</span>';
      assert.equal(builder._formatText(text, 4, 10).innerHTML,
          '&lt;span clas' +
          LINE_FEED_HTML +
          's="thumbsu' +
          LINE_FEED_HTML +
          'p"&gt;👍&lt;/span' +
          LINE_FEED_HTML +
          '&gt;');
    });

    test('newlines 3', () => {
      const text = '01234\t56789';
      assert.equal(builder._formatText(text, 4, 10).innerHTML,
          '01234' + builder._getTabWrapper(3).outerHTML + '56' +
          LINE_FEED_HTML +
          '789');
    });

    test('newlines 4', () => {
      const text = '👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍';
      assert.equal(builder._formatText(text, 4, 20).innerHTML,
          '👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍' +
          LINE_FEED_HTML +
          '👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍' +
          LINE_FEED_HTML +
          '👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍');
    });


    test('line_length ignored if line_wrapping is true', () => {
      builder._prefs = {line_wrapping: true, tab_size: 4, line_length: 50};
      const text = 'a'.repeat(51);

      const line = {text, highlights: []};
      const result = builder._createTextEl(line).firstChild.innerHTML;
      assert.equal(result, text);
    });

    test('line_length applied if line_wrapping is false', () => {
      builder._prefs = {line_wrapping: false, tab_size: 4, line_length: 50};
      const text = 'a'.repeat(51);

      const line = {text, highlights: []};
      const expected = 'a'.repeat(50) + LINE_FEED_HTML + 'a';
      const result = builder._createTextEl(line).firstChild.innerHTML;
      assert.equal(result, expected);
    });

    test('_createTextEl linewrap with tabs', () => {
      const text = '\t'.repeat(7) + '!';
      const line = {text, highlights: []};
      const el = builder._createTextEl(line);
      assert.equal(el.innerText, text);
      // With line length 10 and tab size 2, there should be a line break
      // after every two tabs.
      const newlineEl = el.querySelector('.contentText > .br');
      assert.isOk(newlineEl);
      assert.equal(
          el.querySelector('.contentText .tab:nth-child(2)').nextSibling,
          newlineEl);
    });

    test('text length with tabs and unicode', () => {
      function expectTextLength(text, tabSize, expected) {
        // Formatting to |expected| columns should not introduce line breaks.
        const result = builder._formatText(text, tabSize, expected);
        assert.isNotOk(result.querySelector('.contentText > .br'),
            `  Expected the result of: \n` +
            `      _formatText(${text}', ${tabSize}, ${expected})\n` +
            `  to not contain a br. But the actual result HTML was:\n` +
            `      '${result.innerHTML}'\nwhereupon`);

        // Increasing the line limit should produce the same markup.
        assert.equal(builder._formatText(text, tabSize, Infinity).innerHTML,
            result.innerHTML);
        assert.equal(builder._formatText(text, tabSize, expected + 1).innerHTML,
            result.innerHTML);

        // Decreasing the line limit should introduce line breaks.
        if (expected > 0) {
          const tooSmall = builder._formatText(text, tabSize, expected - 1);
          assert.isOk(tooSmall.querySelector('.contentText > .br'),
              `  Expected the result of: \n` +
              `      _formatText(${text}', ${tabSize}, ${expected - 1})\n` +
              `  to contain a br. But the actual result HTML was:\n` +
              `      '${tooSmall.innerHTML}'\nwhereupon`);
        }
      }
      expectTextLength('12345', 4, 5);
      expectTextLength('\t\t12', 4, 10);
      expectTextLength('abc💢123', 4, 7);
      expectTextLength('abc\t', 8, 8);
      expectTextLength('abc\t\t', 10, 20);
      expectTextLength('', 10, 0);
      expectTextLength('', 10, 0);
      // 17 Thai combining chars.
      expectTextLength('ก้้้้้้้้้้้้้้้้', 4, 17);
      expectTextLength('abc\tde', 10, 12);
      expectTextLength('abc\tde\t', 10, 20);
      expectTextLength('\t\t\t\t\t', 20, 100);
    });

    test('tab wrapper insertion', () => {
      const html = 'abc\tdef';
      const tabSize = builder._prefs.tab_size;
      const wrapper = builder._getTabWrapper(tabSize - 3);
      assert.ok(wrapper);
      assert.equal(wrapper.innerText, '\t');
      assert.equal(
          builder._formatText(html, tabSize, Infinity).innerHTML,
          'abc' + wrapper.outerHTML + 'def');
    });

    test('tab wrapper style', () => {
      const pattern = new RegExp('^<span class="style-scope gr-diff tab" '
          + 'style="(?:-moz-)?tab-size: (\\d+);">\\t<\\/span>$');

      for (const size of [1, 3, 8, 55]) {
        const html = builder._getTabWrapper(size).outerHTML;
        expect(html).to.match(pattern);
        assert.equal(html.match(pattern)[1], size);
      }
    });

    test('comment thread group creation', () => {
      const l3 = document.createElement('div');
      l3.className = 'comment-thread';
      l3.setAttribute('comment-side', 'left');
      l3.setAttribute('line-num', 3);

      const l5 = document.createElement('div');
      l5.className = 'comment-thread';
      l5.setAttribute('comment-side', 'left');
      l5.setAttribute('line-num', 5);

      const r5 = document.createElement('div');
      r5.className = 'comment-thread';
      r5.setAttribute('comment-side', 'right');
      r5.setAttribute('line-num', 5);

      builder = new GrDiffBuilder({content: []}, [l3, l5, r5], prefs);

      function checkThreadGroupProps(threadGroupEl,
          expectedThreadEls) {
        const threadEls = Polymer.dom(threadGroupEl).queryDistributedElements(
            '.comment-thread');
        assert.equal(threadEls.length, expectedThreadEls.length);
        for (let i=0; i<expectedThreadEls.length; i++) {
          assert.equal(threadEls[i], expectedThreadEls[i]);
        }
      }

      let line = new GrDiffLine(GrDiffLine.Type.BOTH);
      line.beforeNumber = 5;
      line.afterNumber = 5;
      let threadGroupEl = builder._commentThreadGroupForLine(line);
      checkThreadGroupProps(threadGroupEl, [l5, r5]);

      threadGroupEl =
          builder._commentThreadGroupForLine(line, GrDiffBuilder.Side.RIGHT);
      checkThreadGroupProps(threadGroupEl, [r5]);

      threadGroupEl =
          builder._commentThreadGroupForLine(line, GrDiffBuilder.Side.LEFT);
      checkThreadGroupProps(threadGroupEl, [l5]);

      threadGroupEl = builder._commentThreadGroupForLine(line);
      checkThreadGroupProps(threadGroupEl, [l5, r5]);

      threadEl =
          builder._commentThreadGroupForLine(line, GrDiffBuilder.Side.LEFT);
      checkThreadGroupProps(threadEl, [l5]);

      threadGroupEl =
          builder._commentThreadGroupForLine(line, GrDiffBuilder.Side.RIGHT);
      checkThreadGroupProps(threadGroupEl, [r5]);

      line = new GrDiffLine(GrDiffLine.Type.REMOVE);
      line.beforeNumber = 5;
      line.afterNumber = 5;
      threadGroupEl = builder._commentThreadGroupForLine(line);
      checkThreadGroupProps(threadGroupEl, [l5, r5]);

      line = new GrDiffLine(GrDiffLine.Type.ADD);
      line.beforeNumber = 3;
      line.afterNumber = 5;
      threadGroupEl = builder._commentThreadGroupForLine(line);
      checkThreadGroupProps(threadGroupEl, [l3, r5]);
    });


    test('_handlePreferenceError called with invalid preference', () => {
      sandbox.stub(element, '_handlePreferenceError');
      const prefs = {tab_size: 0};
      element._getDiffBuilder(element.diff, prefs);
      assert.isTrue(element._handlePreferenceError.lastCall
          .calledWithExactly('tab size'));
    });

    test('_handlePreferenceError triggers alert and javascript error', () => {
      const errorStub = sinon.stub();
      element.addEventListener('show-alert', errorStub);
      assert.throws(element._handlePreferenceError.bind(element, 'tab size'));
      assert.equal(errorStub.lastCall.args[0].detail.message,
          `The value of the 'tab size' user preference is invalid. ` +
        `Fix in diff preferences`);
    });

    suite('_isTotal', () => {
      test('is total for add', () => {
        const group = new GrDiffGroup(GrDiffGroup.Type.DELTA);
        for (let idx = 0; idx < 10; idx++) {
          group.addLine(new GrDiffLine(GrDiffLine.Type.ADD));
        }
        assert.isTrue(GrDiffBuilder.prototype._isTotal(group));
      });

      test('is total for remove', () => {
        const group = new GrDiffGroup(GrDiffGroup.Type.DELTA);
        for (let idx = 0; idx < 10; idx++) {
          group.addLine(new GrDiffLine(GrDiffLine.Type.REMOVE));
        }
        assert.isTrue(GrDiffBuilder.prototype._isTotal(group));
      });

      test('not total for empty', () => {
        const group = new GrDiffGroup(GrDiffGroup.Type.BOTH);
        assert.isFalse(GrDiffBuilder.prototype._isTotal(group));
      });

      test('not total for non-delta', () => {
        const group = new GrDiffGroup(GrDiffGroup.Type.DELTA);
        for (let idx = 0; idx < 10; idx++) {
          group.addLine(new GrDiffLine(GrDiffLine.Type.BOTH));
        }
        assert.isFalse(GrDiffBuilder.prototype._isTotal(group));
      });
    });

    suite('intraline differences', () => {
      let el;
      let str;
      let annotateElementSpy;
      let layer;

      function slice(str, start, end) {
        return Array.from(str).slice(start, end).join('');
      }

      setup(() => {
        el = fixture('div-with-text');
        str = el.textContent;
        annotateElementSpy = sandbox.spy(GrAnnotation, 'annotateElement');
        layer = document.createElement('gr-diff-builder')
            ._createIntralineLayer();
      });

      test('annotate no highlights', () => {
        const line = {
          text: str,
          highlights: [],
        };

        layer.annotate(el, line);

        // The content is unchanged.
        assert.isFalse(annotateElementSpy.called);
        assert.equal(el.childNodes.length, 1);
        assert.instanceOf(el.childNodes[0], Text);
        assert.equal(str, el.childNodes[0].textContent);
      });

      test('annotate with highlights', () => {
        const line = {
          text: str,
          highlights: [
            {startIndex: 6, endIndex: 12},
            {startIndex: 18, endIndex: 22},
          ],
        };
        const str0 = slice(str, 0, 6);
        const str1 = slice(str, 6, 12);
        const str2 = slice(str, 12, 18);
        const str3 = slice(str, 18, 22);
        const str4 = slice(str, 22);

        layer.annotate(el, line);

        assert.isTrue(annotateElementSpy.called);
        assert.equal(el.childNodes.length, 5);

        assert.instanceOf(el.childNodes[0], Text);
        assert.equal(el.childNodes[0].textContent, str0);

        assert.notInstanceOf(el.childNodes[1], Text);
        assert.equal(el.childNodes[1].textContent, str1);

        assert.instanceOf(el.childNodes[2], Text);
        assert.equal(el.childNodes[2].textContent, str2);

        assert.notInstanceOf(el.childNodes[3], Text);
        assert.equal(el.childNodes[3].textContent, str3);

        assert.instanceOf(el.childNodes[4], Text);
        assert.equal(el.childNodes[4].textContent, str4);
      });

      test('annotate without endIndex', () => {
        const line = {
          text: str,
          highlights: [
            {startIndex: 28},
          ],
        };

        const str0 = slice(str, 0, 28);
        const str1 = slice(str, 28);

        layer.annotate(el, line);

        assert.isTrue(annotateElementSpy.called);
        assert.equal(el.childNodes.length, 2);

        assert.instanceOf(el.childNodes[0], Text);
        assert.equal(el.childNodes[0].textContent, str0);

        assert.notInstanceOf(el.childNodes[1], Text);
        assert.equal(el.childNodes[1].textContent, str1);
      });

      test('annotate ignores empty highlights', () => {
        const line = {
          text: str,
          highlights: [
            {startIndex: 28, endIndex: 28},
          ],
        };

        layer.annotate(el, line);

        assert.isFalse(annotateElementSpy.called);
        assert.equal(el.childNodes.length, 1);
      });

      test('annotate handles unicode', () => {
        // Put some unicode into the string:
        str = str.replace(/\s/g, '💢');
        el.textContent = str;
        const line = {
          text: str,
          highlights: [
            {startIndex: 6, endIndex: 12},
          ],
        };

        const str0 = slice(str, 0, 6);
        const str1 = slice(str, 6, 12);
        const str2 = slice(str, 12);

        layer.annotate(el, line);

        assert.isTrue(annotateElementSpy.called);
        assert.equal(el.childNodes.length, 3);

        assert.instanceOf(el.childNodes[0], Text);
        assert.equal(el.childNodes[0].textContent, str0);

        assert.notInstanceOf(el.childNodes[1], Text);
        assert.equal(el.childNodes[1].textContent, str1);

        assert.instanceOf(el.childNodes[2], Text);
        assert.equal(el.childNodes[2].textContent, str2);
      });

      test('annotate handles unicode w/o endIndex', () => {
        // Put some unicode into the string:
        str = str.replace(/\s/g, '💢');
        el.textContent = str;

        const line = {
          text: str,
          highlights: [
            {startIndex: 6},
          ],
        };

        const str0 = slice(str, 0, 6);
        const str1 = slice(str, 6);

        layer.annotate(el, line);

        assert.isTrue(annotateElementSpy.called);
        assert.equal(el.childNodes.length, 2);

        assert.instanceOf(el.childNodes[0], Text);
        assert.equal(el.childNodes[0].textContent, str0);

        assert.notInstanceOf(el.childNodes[1], Text);
        assert.equal(el.childNodes[1].textContent, str1);
      });
    });

    suite('tab indicators', () => {
      let element;
      let layer;

      setup(() => {
        element = fixture('basic');
        element._showTabs = true;
        layer = element._createTabIndicatorLayer();
      });

      test('does nothing with empty line', () => {
        const line = {text: ''};
        const el = document.createElement('div');
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');

        layer.annotate(el, line);

        assert.isFalse(annotateElementStub.called);
      });

      test('does nothing with no tabs', () => {
        const str = 'lorem ipsum no tabs';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');

        layer.annotate(el, line);

        assert.isFalse(annotateElementStub.called);
      });

      test('annotates tab at beginning', () => {
        const str = '\tlorem upsum';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');

        layer.annotate(el, line);

        assert.equal(annotateElementStub.callCount, 1);
        const args = annotateElementStub.getCalls()[0].args;
        assert.equal(args[0], el);
        assert.equal(args[1], 0, 'offset of tab indicator');
        assert.equal(args[2], 1, 'length of tab indicator');
        assert.include(args[3], 'tab-indicator');
      });

      test('does not annotate when disabled', () => {
        element._showTabs = false;

        const str = '\tlorem upsum';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');

        layer.annotate(el, line);

        assert.isFalse(annotateElementStub.called);
      });

      test('annotates multiple in beginning', () => {
        const str = '\t\tlorem upsum';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');

        layer.annotate(el, line);

        assert.equal(annotateElementStub.callCount, 2);

        let args = annotateElementStub.getCalls()[0].args;
        assert.equal(args[0], el);
        assert.equal(args[1], 0, 'offset of tab indicator');
        assert.equal(args[2], 1, 'length of tab indicator');
        assert.include(args[3], 'tab-indicator');

        args = annotateElementStub.getCalls()[1].args;
        assert.equal(args[0], el);
        assert.equal(args[1], 1, 'offset of tab indicator');
        assert.equal(args[2], 1, 'length of tab indicator');
        assert.include(args[3], 'tab-indicator');
      });

      test('annotates intermediate tabs', () => {
        const str = 'lorem\tupsum';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');

        layer.annotate(el, line);

        assert.equal(annotateElementStub.callCount, 1);
        const args = annotateElementStub.getCalls()[0].args;
        assert.equal(args[0], el);
        assert.equal(args[1], 5, 'offset of tab indicator');
        assert.equal(args[2], 1, 'length of tab indicator');
        assert.include(args[3], 'tab-indicator');
      });
    });

    suite('layers from plugins', () => {
      let element;
      let initialLayersCount;

      setup(() => {
        element = fixture('basic');
        element._showTrailingWhitespace = true;
        initialLayersCount = element._layers.length;
      });

      test('no plugin layers', () => {
        const getDiffLayersStub = sinon.stub(element.$.jsAPI, 'getDiffLayers')
                                       .returns([]);
        element.attached();
        assert.isTrue(getDiffLayersStub.called);
        assert.equal(element._layers.length, initialLayersCount);
      });

      test('with plugin layers', () => {
        const getDiffLayersStub = sinon.stub(element.$.jsAPI, 'getDiffLayers')
                                       .returns([{}, {}]);
        element.attached();
        assert.isTrue(getDiffLayersStub.called);
        assert.equal(element._layers.length, initialLayersCount+2);
      });
    });

    suite('trailing whitespace', () => {
      let element;
      let layer;

      setup(() => {
        element = fixture('basic');
        element._showTrailingWhitespace = true;
        layer = element._createTrailingWhitespaceLayer();
      });

      test('does nothing with empty line', () => {
        const line = {text: ''};
        const el = document.createElement('div');
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isFalse(annotateElementStub.called);
      });

      test('does nothing with no trailing whitespace', () => {
        const str = 'lorem ipsum blah blah';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isFalse(annotateElementStub.called);
      });

      test('annotates trailing spaces', () => {
        const str = 'lorem ipsum   ';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isTrue(annotateElementStub.called);
        assert.equal(annotateElementStub.lastCall.args[1], 11);
        assert.equal(annotateElementStub.lastCall.args[2], 3);
      });

      test('annotates trailing tabs', () => {
        const str = 'lorem ipsum\t\t\t';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isTrue(annotateElementStub.called);
        assert.equal(annotateElementStub.lastCall.args[1], 11);
        assert.equal(annotateElementStub.lastCall.args[2], 3);
      });

      test('annotates mixed trailing whitespace', () => {
        const str = 'lorem ipsum\t \t';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isTrue(annotateElementStub.called);
        assert.equal(annotateElementStub.lastCall.args[1], 11);
        assert.equal(annotateElementStub.lastCall.args[2], 3);
      });

      test('unicode preceding trailing whitespace', () => {
        const str = '💢\t';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isTrue(annotateElementStub.called);
        assert.equal(annotateElementStub.lastCall.args[1], 1);
        assert.equal(annotateElementStub.lastCall.args[2], 1);
      });

      test('does not annotate when disabled', () => {
        element._showTrailingWhitespace = false;
        const str = 'lorem upsum\t \t ';
        const line = {text: str};
        const el = document.createElement('div');
        el.textContent = str;
        const annotateElementStub =
            sandbox.stub(GrAnnotation, 'annotateElement');
        layer.annotate(el, line);
        assert.isFalse(annotateElementStub.called);
      });
    });

    suite('rendering text, images and binary files', () => {
      let processStub;
      let keyLocations;
      let prefs;
      let content;

      setup(() => {
        element = fixture('basic');
        element.viewMode = 'SIDE_BY_SIDE';
        processStub = sandbox.stub(element.$.processor, 'process')
            .returns(Promise.resolve());
        sandbox.stub(element, '_anyLineTooLong').returns(true);
        keyLocations = {left: {}, right: {}};
        prefs = {
          line_length: 10,
          show_tabs: true,
          tab_size: 4,
          context: -1,
          syntax_highlighting: true,
        };
        content = [{
          a: ['all work and no play make andybons a dull boy'],
          b: ['elgoog elgoog elgoog'],
        }, {
          ab: [
            'Non eram nescius, Brute, cum, quae summis ingeniis ',
            'exquisitaque doctrina philosophi Graeco sermone tractavissent',
          ],
        }];
      });

      test('text', () => {
        element.diff = {content};
        return element.render(keyLocations, prefs).then(() => {
          assert.isTrue(processStub.calledOnce);
          assert.isFalse(processStub.lastCall.args[1]);
        });
      });

      test('image', () => {
        element.diff = {content, binary: true};
        element.isImageDiff = true;
        return element.render(keyLocations, prefs).then(() => {
          assert.isTrue(processStub.calledOnce);
          assert.isTrue(processStub.lastCall.args[1]);
        });
      });

      test('binary', () => {
        element.diff = {content, binary: true};
        return element.render(keyLocations, prefs).then(() => {
          assert.isTrue(processStub.calledOnce);
          assert.isTrue(processStub.lastCall.args[1]);
        });
      });
    });

    suite('rendering', () => {
      let content;
      let outputEl;
      let keyLocations;

      setup(done => {
        const prefs = {
          line_length: 10,
          show_tabs: true,
          tab_size: 4,
          context: -1,
          syntax_highlighting: true,
        };
        content = [
          {
            a: ['all work and no play make andybons a dull boy'],
            b: ['elgoog elgoog elgoog'],
          },
          {
            ab: [
              'Non eram nescius, Brute, cum, quae summis ingeniis ',
              'exquisitaque doctrina philosophi Graeco sermone tractavissent',
            ],
          },
        ];
        stub('gr-reporting', {
          time: sandbox.stub(),
          timeEnd: sandbox.stub(),
        });
        element = fixture('basic');
        outputEl = element.queryEffectiveChildren('#diffTable');
        keyLocations = {left: {}, right: {}};
        sandbox.stub(element, '_getDiffBuilder', () => {
          const builder = new GrDiffBuilder({content}, [], prefs, outputEl);
          sandbox.stub(builder, 'addColumns');
          builder.buildSectionElement = function(group) {
            const section = document.createElement('stub');
            section.textContent = group.lines.reduce((acc, line) => {
              return acc + line.text;
            }, '');
            return section;
          };
          return builder;
        });
        element.diff = {content};
        element.render(keyLocations, prefs).then(done);
      });

      test('reporting', done => {
        const timeStub = element.$.reporting.time;
        const timeEndStub = element.$.reporting.timeEnd;
        assert.isTrue(timeStub.calledWithExactly('Diff Total Render'));
        assert.isTrue(timeStub.calledWithExactly('Diff Content Render'));
        assert.isTrue(timeStub.calledWithExactly('Diff Syntax Render'));
        assert.isTrue(timeEndStub.calledWithExactly('Diff Total Render'));
        assert.isTrue(timeEndStub.calledWithExactly('Diff Content Render'));
        assert.isTrue(timeEndStub.calledWithExactly('Diff Syntax Render'));
        done();
      });

      test('renderSection', () => {
        let section = outputEl.querySelector('stub:nth-of-type(2)');
        const prevInnerHTML = section.innerHTML;
        section.innerHTML = 'wiped';
        element._builder.renderSection(section);
        section = outputEl.querySelector('stub:nth-of-type(2)');
        assert.equal(section.innerHTML, prevInnerHTML);
      });

      test('addColumns is called', done => {
        element.render(keyLocations, {}).then(done);
        assert.isTrue(element._builder.addColumns.called);
      });

      test('getSectionsByLineRange one line', () => {
        const section = outputEl.querySelector('stub:nth-of-type(2)');
        const sections = element._builder.getSectionsByLineRange(1, 1, 'left');
        assert.equal(sections.length, 1);
        assert.strictEqual(sections[0], section);
      });

      test('getSectionsByLineRange over diff', () => {
        const section = [
          outputEl.querySelector('stub:nth-of-type(2)'),
          outputEl.querySelector('stub:nth-of-type(3)'),
        ];
        const sections = element._builder.getSectionsByLineRange(1, 2, 'left');
        assert.equal(sections.length, 2);
        assert.strictEqual(sections[0], section[0]);
        assert.strictEqual(sections[1], section[1]);
      });

      test('render-start and render are fired', done => {
        const dispatchEventStub = sandbox.stub(element, 'dispatchEvent');
        element.render(keyLocations, {}).then(() => {
          const firedEventTypes = dispatchEventStub.getCalls()
              .map(c => { return c.args[0].type; });
          assert.include(firedEventTypes, 'render-start');
          assert.include(firedEventTypes, 'render-content');
          assert.include(firedEventTypes, 'render');
          done();
        });
      });

      test('rendering normal-sized diff does not disable syntax', () => {
        assert.isTrue(element.$.syntaxLayer.enabled);
      });

      test('rendering large diff disables syntax', done => {
        // Before it renders, set the first diff line to 500 '*' characters.
        element.diff.content[0].a = [new Array(501).join('*')];
        element.addEventListener('render', () => {
          assert.isFalse(element.$.syntaxLayer.enabled);
          done();
        });
        const prefs = {
          line_length: 10,
          show_tabs: true,
          tab_size: 4,
          context: -1,
          syntax_highlighting: true,
        };
        element.render(keyLocations, prefs);
      });

      test('cancel', () => {
        const processorCancelStub = sandbox.stub(element.$.processor, 'cancel');
        const syntaxCancelStub = sandbox.stub(element.$.syntaxLayer, 'cancel');
        element.cancel();
        assert.isTrue(processorCancelStub.called);
        assert.isTrue(syntaxCancelStub.called);
      });
    });

    suite('mock-diff', () => {
      let element;
      let builder;
      let diff;
      let prefs;
      let keyLocations;

      setup(done => {
        element = fixture('mock-diff');
        diff = document.createElement('mock-diff-response').diffResponse;
        element.diff = diff;

        prefs = {
          line_length: 80,
          show_tabs: true,
          tab_size: 4,
        };
        keyLocations = {left: {}, right: {}};

        element.render(keyLocations, prefs).then(() => {
          builder = element._builder;
          done();
        });
      });

      test('getDiffLength', () => {
        assert.equal(element.getDiffLength(diff), 52);
      });

      test('getContentByLine', () => {
        let actual;

        actual = builder.getContentByLine(2, 'left');
        assert.equal(actual.textContent, diff.content[0].ab[1]);

        actual = builder.getContentByLine(2, 'right');
        assert.equal(actual.textContent, diff.content[0].ab[1]);

        actual = builder.getContentByLine(5, 'left');
        assert.equal(actual.textContent, diff.content[2].ab[0]);

        actual = builder.getContentByLine(5, 'right');
        assert.equal(actual.textContent, diff.content[1].b[0]);
      });

      test('findLinesByRange', () => {
        const lines = [];
        const elems = [];
        const start = 6;
        const end = 10;
        const count = end - start + 1;

        builder.findLinesByRange(start, end, 'right', lines, elems);

        assert.equal(lines.length, count);
        assert.equal(elems.length, count);

        for (let i = 0; i < 5; i++) {
          assert.instanceOf(lines[i], GrDiffLine);
          assert.equal(lines[i].afterNumber, start + i);
          assert.instanceOf(elems[i], HTMLElement);
          assert.equal(lines[i].text, elems[i].textContent);
        }
      });

      test('_renderContentByRange', () => {
        const spy = sandbox.spy(builder, '_createTextEl');
        const start = 9;
        const end = 14;
        const count = end - start + 1;

        builder._renderContentByRange(start, end, 'left');

        assert.equal(spy.callCount, count);
        spy.getCalls().forEach((call, i) => {
          assert.equal(call.args[0].beforeNumber, start + i);
        });
      });

      test('_renderContentByRange notexistent elements', () => {
        const spy = sandbox.spy(builder, '_createTextEl');

        sandbox.stub(builder, 'findLinesByRange',
            (s, e, d, lines, elements) => {
              // Add a line and a corresponding element.
              lines.push(new GrDiffLine(GrDiffLine.Type.BOTH));
              const parEl = document.createElement('div');
              const el = document.createElement('div');
              parEl.appendChild(el);
              elements.push(el);

              // Add 2 lines without corresponding elements.
              lines.push(new GrDiffLine(GrDiffLine.Type.BOTH));
              lines.push(new GrDiffLine(GrDiffLine.Type.BOTH));
            });

        builder._renderContentByRange(1, 10, 'left');
        // Should be called only once because only one line had a corresponding
        // element.
        assert.equal(spy.callCount, 1);
      });

      test('_getNextContentOnSide side-by-side left', () => {
        const startElem = builder.getContentByLine(5, 'left',
            element.$.diffTable);
        const expectedStartString = diff.content[2].ab[0];
        const expectedNextString = diff.content[2].ab[1];
        assert.equal(startElem.textContent, expectedStartString);

        const nextElem = builder._getNextContentOnSide(startElem,
            'left');
        assert.equal(nextElem.textContent, expectedNextString);
      });

      test('_getNextContentOnSide side-by-side right', () => {
        const startElem = builder.getContentByLine(5, 'right',
            element.$.diffTable);
        const expectedStartString = diff.content[1].b[0];
        const expectedNextString = diff.content[1].b[1];
        assert.equal(startElem.textContent, expectedStartString);

        const nextElem = builder._getNextContentOnSide(startElem,
            'right');
        assert.equal(nextElem.textContent, expectedNextString);
      });

      test('_getNextContentOnSide unified left', done => {
        // Re-render as unified:
        element.viewMode = 'UNIFIED_DIFF';
        element.render(keyLocations, prefs).then(() => {
          builder = element._builder;

          const startElem = builder.getContentByLine(5, 'left',
              element.$.diffTable);
          const expectedStartString = diff.content[2].ab[0];
          const expectedNextString = diff.content[2].ab[1];
          assert.equal(startElem.textContent, expectedStartString);

          const nextElem = builder._getNextContentOnSide(startElem,
              'left');
          assert.equal(nextElem.textContent, expectedNextString);

          done();
        });
      });

      test('_getNextContentOnSide unified right', done => {
        // Re-render as unified:
        element.viewMode = 'UNIFIED_DIFF';
        element.render(keyLocations, prefs).then(() => {
          builder = element._builder;

          const startElem = builder.getContentByLine(5, 'right',
              element.$.diffTable);
          const expectedStartString = diff.content[1].b[0];
          const expectedNextString = diff.content[1].b[1];
          assert.equal(startElem.textContent, expectedStartString);

          const nextElem = builder._getNextContentOnSide(startElem,
              'right');
          assert.equal(nextElem.textContent, expectedNextString);

          done();
        });
      });

      test('escaping HTML', () => {
        let input = '<script>alert("XSS");<' + '/script>';
        let expected = '&lt;script&gt;alert("XSS");&lt;/script&gt;';
        let result = builder._formatText(input, 1, Infinity).innerHTML;
        assert.equal(result, expected);

        input = '& < > " \' / `';
        expected = '&amp; &lt; &gt; " \' / `';
        result = builder._formatText(input, 1, Infinity).innerHTML;
        assert.equal(result, expected);
      });
    });

    suite('blame', () => {
      let mockBlame;

      setup(() => {
        mockBlame = [
          {id: 'commit 1', ranges: [{start: 1, end: 2}, {start: 10, end: 16}]},
          {id: 'commit 2', ranges: [{start: 4, end: 10}, {start: 17, end: 32}]},
        ];
      });

      test('setBlame attempts to render each blamed line', () => {
        const getBlameStub = sandbox.stub(builder, '_getBlameByLineNum')
            .returns(null);
        builder.setBlame(mockBlame);
        assert.equal(getBlameStub.callCount, 32);
      });

      test('_getBlameCommitForBaseLine', () => {
        builder.setBlame(mockBlame);
        assert.isOk(builder._getBlameCommitForBaseLine(1));
        assert.equal(builder._getBlameCommitForBaseLine(1).id, 'commit 1');

        assert.isOk(builder._getBlameCommitForBaseLine(11));
        assert.equal(builder._getBlameCommitForBaseLine(11).id, 'commit 1');

        assert.isOk(builder._getBlameCommitForBaseLine(32));
        assert.equal(builder._getBlameCommitForBaseLine(32).id, 'commit 2');

        assert.isNull(builder._getBlameCommitForBaseLine(33));
      });

      test('_getBlameCommitForBaseLine w/o blame returns null', () => {
        assert.isNull(builder._getBlameCommitForBaseLine(1));
        assert.isNull(builder._getBlameCommitForBaseLine(11));
        assert.isNull(builder._getBlameCommitForBaseLine(31));
      });

      test('_createBlameCell', () => {
        const mocbBlameCell = document.createElement('span');
        const getBlameStub = sinon.stub(builder, '_getBlameForBaseLine')
            .returns(mocbBlameCell);
        const line = new GrDiffLine(GrDiffLine.Type.BOTH);
        line.beforeNumber = 3;
        line.afterNumber = 5;

        const result = builder._createBlameCell(line);

        assert.isTrue(getBlameStub.calledWithExactly(3));
        assert.equal(result.getAttribute('data-line-number'), '3');
        assert.equal(result.firstChild, mocbBlameCell);
      });
    });
  });
</script>