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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-view</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="../../../bower_components/page/page.js"></script>
<script src="../../../scripts/util.js"></script>

<link rel="import" href="gr-diff-view.html">

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

<test-fixture id="basic">
  <template>
    <gr-diff-view></gr-diff-view>
  </template>
</test-fixture>

<test-fixture id="blank">
  <template>
    <div></div>
  </template>
</test-fixture>

<script>
  suite('gr-diff-view tests', () => {
    let element;
    let sandbox;

    setup(() => {
      sandbox = sinon.sandbox.create();

      stub('gr-rest-api-interface', {
        getLoggedIn() { return Promise.resolve(false); },
        getProjectConfig() { return Promise.resolve({}); },
        getDiffChangeDetail() { return Promise.resolve(null); },
        getChangeFiles() { return Promise.resolve({}); },
        saveFileReviewed() { return Promise.resolve(); },
        getDiffRobotComments() { return Promise.resolve(); },
        getDiffDrafts() { return Promise.resolve(); },
      });
      element = fixture('basic');
    });

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

    test('toggle left diff with a hotkey', () => {
      const toggleLeftDiffStub = sandbox.stub(element.$.diff, 'toggleLeftDiff');
      MockInteractions.pressAndReleaseKeyOn(element, 65, 'shift', 'a');
      assert.isTrue(toggleLeftDiffStub.calledOnce);
    });

    test('keyboard shortcuts', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: 'PARENT',
        patchNum: '10',
      };
      element._change = {
        revisions: {
          a: {_number: 10},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      element.changeViewState.selectedFileIndex = 1;

      const showStub = sandbox.stub(page, 'show');
      MockInteractions.pressAndReleaseKeyOn(element, 85, null, 'u');
      assert(showStub.lastCall.calledWithExactly('/c/42/'),
          'Should navigate to /c/42/');

      MockInteractions.pressAndReleaseKeyOn(element, 221, null, ']');
      assert(showStub.lastCall.calledWithExactly('/c/42/10/wheatley.md'),
          'Should navigate to /c/42/10/wheatley.md');
      element._path = 'wheatley.md';
      assert.equal(element.changeViewState.selectedFileIndex, 2);

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/10/glados.txt'),
          'Should navigate to /c/42/10/glados.txt');
      element._path = 'glados.txt';
      assert.equal(element.changeViewState.selectedFileIndex, 1);

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/10/chell.go'),
          'Should navigate to /c/42/10/chell.go');
      element._path = 'chell.go';
      assert.equal(element.changeViewState.selectedFileIndex, 0);

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/'),
          'Should navigate to /c/42/');
      assert.equal(element.changeViewState.selectedFileIndex, 0);

      const showPrefsStub =
          sandbox.stub(element.$.diffPreferences.$.prefsOverlay, 'open',
              () => Promise.resolve());

      MockInteractions.pressAndReleaseKeyOn(element, 188, null, ',');
      assert(showPrefsStub.calledOnce);

      let scrollStub = sandbox.stub(element.$.cursor, 'moveToNextChunk');
      MockInteractions.pressAndReleaseKeyOn(element, 78, null, 'n');
      assert(scrollStub.calledOnce);

      scrollStub = sandbox.stub(element.$.cursor, 'moveToPreviousChunk');
      MockInteractions.pressAndReleaseKeyOn(element, 80, null, 'p');
      assert(scrollStub.calledOnce);

      scrollStub = sandbox.stub(element.$.cursor, 'moveToNextCommentThread');
      MockInteractions.pressAndReleaseKeyOn(element, 78, 'shift', 'n');
      assert(scrollStub.calledOnce);

      scrollStub = sandbox.stub(element.$.cursor,
          'moveToPreviousCommentThread');
      MockInteractions.pressAndReleaseKeyOn(element, 80, 'shift', 'p');
      assert(scrollStub.calledOnce);

      const computeContainerClassStub = sandbox.stub(element.$.diff,
          '_computeContainerClass');
      MockInteractions.pressAndReleaseKeyOn(element, 74, null, 'j');
      assert(computeContainerClassStub.lastCall.calledWithExactly(
          false, 'SIDE_BY_SIDE', true));

      MockInteractions.pressAndReleaseKeyOn(element, 27, null, 'esc');
      assert(computeContainerClassStub.lastCall.calledWithExactly(
          false, 'SIDE_BY_SIDE', false));
    });

    test('keyboard shortcuts with patch range', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: '5',
        patchNum: '10',
      };
      element._change = {
        revisions: {
          a: {_number: 10},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';

      const showStub = sandbox.stub(page, 'show');

      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(showStub.notCalled, 'The `a` keyboard shortcut should ' +
          'only work when the user is logged in.');
      assert.isNull(window.sessionStorage.getItem(
          'changeView.showReplyDialog'));

      element._loggedIn = true;
      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(element.changeViewState.showReplyDialog);

      assert(showStub.lastCall.calledWithExactly('/c/42/5..10'),
          'Should navigate to /c/42/5..10');

      MockInteractions.pressAndReleaseKeyOn(element, 85, null, 'u');
      assert(showStub.lastCall.calledWithExactly('/c/42/5..10'),
          'Should navigate to /c/42/5..10');

      MockInteractions.pressAndReleaseKeyOn(element, 221, null, ']');
      assert(showStub.lastCall.calledWithExactly('/c/42/5..10/wheatley.md'),
          'Should navigate to /c/42/5..10/wheatley.md');
      element._path = 'wheatley.md';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/5..10/glados.txt'),
          'Should navigate to /c/42/5..10/glados.txt');
      element._path = 'glados.txt';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/5..10/chell.go'),
          'Should navigate to /c/42/5..10/chell.go');
      element._path = 'chell.go';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/5..10'),
          'Should navigate to /c/42/5..10');
    });

    test('keyboard shortcuts with old patch number', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: 'PARENT',
        patchNum: '1',
      };
      element._change = {
        revisions: {
          a: {_number: 1},
          b: {_number: 2},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';

      const showStub = sandbox.stub(page, 'show');

      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(showStub.notCalled, 'The `a` keyboard shortcut should ' +
          'only work when the user is logged in.');
      assert.isNull(window.sessionStorage.getItem(
          'changeView.showReplyDialog'));

      element._loggedIn = true;
      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(element.changeViewState.showReplyDialog);

      assert(showStub.lastCall.calledWithExactly('/c/42/1'),
          'Should navigate to /c/42/1');

      MockInteractions.pressAndReleaseKeyOn(element, 85, null, 'u');
      assert(showStub.lastCall.calledWithExactly('/c/42/1'),
          'Should navigate to /c/42/1');

      MockInteractions.pressAndReleaseKeyOn(element, 221, null, ']');
      assert(showStub.lastCall.calledWithExactly('/c/42/1/wheatley.md'),
          'Should navigate to /c/42/1/wheatley.md');
      element._path = 'wheatley.md';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/1/glados.txt'),
          'Should navigate to /c/42/1/glados.txt');
      element._path = 'glados.txt';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/1/chell.go'),
          'Should navigate to /c/42/1/chell.go');
      element._path = 'chell.go';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/1'),
          'Should navigate to /c/42/1');
    });

    test('Diff preferences hidden when no prefs or logged out', () => {
      element._loggedIn = false;
      flushAsynchronousOperations();
      assert.isTrue(element.$.diffPrefsContainer.hidden);

      element._loggedIn = true;
      flushAsynchronousOperations();
      assert.isTrue(element.$.diffPrefsContainer.hidden);

      element._loggedIn = false;
      element._prefs = {font_size: '12'};
      flushAsynchronousOperations();
      assert.isTrue(element.$.diffPrefsContainer.hidden);

      element._loggedIn = true;
      flushAsynchronousOperations();
      assert.isFalse(element.$.diffPrefsContainer.hidden);
    });

    test('prefsButton opens gr-diff-preferences', () => {
      const handlePrefsTapSpy = sandbox.spy(element, '_handlePrefsTap');
      const overlayOpenStub = sandbox.stub(element.$.diffPreferences,
          'open');
      const prefsButton =
          Polymer.dom(element.root).querySelector('.prefsButton');

      MockInteractions.tap(prefsButton);

      assert.isTrue(handlePrefsTapSpy.called);
      assert.isTrue(overlayOpenStub.called);
    });

    test('go up to change via kb without change loaded', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: 'PARENT',
        patchNum: '1',
      };

      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';

      const showStub = sandbox.stub(page, 'show');

      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(showStub.notCalled, 'The `a` keyboard shortcut should ' +
          'only work when the user is logged in.');
      assert.isNull(window.sessionStorage.getItem(
          'changeView.showReplyDialog'));

      element._loggedIn = true;
      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(element.changeViewState.showReplyDialog);

      assert(showStub.lastCall.calledWithExactly('/c/42/1'),
          'Should navigate to /c/42/1');

      MockInteractions.pressAndReleaseKeyOn(element, 85, null, 'u');
      assert(showStub.lastCall.calledWithExactly('/c/42/1'),
          'Should navigate to /c/42/1');

      MockInteractions.pressAndReleaseKeyOn(element, 221, null, ']');
      assert(showStub.lastCall.calledWithExactly('/c/42/1/wheatley.md'),
          'Should navigate to /c/42/1/wheatley.md');
      element._path = 'wheatley.md';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/1/glados.txt'),
          'Should navigate to /c/42/1/glados.txt');
      element._path = 'glados.txt';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/1/chell.go'),
          'Should navigate to /c/42/1/chell.go');
      element._path = 'chell.go';

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(showStub.lastCall.calledWithExactly('/c/42/1'),
          'Should navigate to /c/42/1');
    });

    test('jump to file dropdown', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: 'PARENT',
        patchNum: '10',
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      flushAsynchronousOperations();
      const linkEls =
          Polymer.dom(element.root).querySelectorAll('.dropdown-content > a');
      assert.equal(linkEls.length, 3);
      assert.isFalse(linkEls[0].hasAttribute('selected'));
      assert.isTrue(linkEls[1].hasAttribute('selected'));
      assert.isFalse(linkEls[2].hasAttribute('selected'));
      assert.equal(linkEls[0].getAttribute('data-key-nav'), '[');
      assert.equal(linkEls[1].getAttribute('data-key-nav'), '');
      assert.equal(linkEls[2].getAttribute('data-key-nav'), ']');
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/10/chell.go');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/10/glados.txt');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/10/wheatley.md');

      assert.equal(element._computeFileDisplayName('/foo/bar/baz'),
          '/foo/bar/baz');
      assert.equal(element._computeFileDisplayName('/COMMIT_MSG'),
          'Commit message');
      assert.equal(element._computeFileDisplayName('/MERGE_LIST'),
          'Merge list');
    });

    test('jump to file dropdown with patch range', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: '5',
        patchNum: '10',
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      flushAsynchronousOperations();
      const linkEls =
          Polymer.dom(element.root).querySelectorAll('.dropdown-content > a');
      assert.equal(linkEls.length, 3);
      assert.isFalse(linkEls[0].hasAttribute('selected'));
      assert.isTrue(linkEls[1].hasAttribute('selected'));
      assert.isFalse(linkEls[2].hasAttribute('selected'));
      assert.equal(linkEls[0].getAttribute('data-key-nav'), '[');
      assert.equal(linkEls[1].getAttribute('data-key-nav'), '');
      assert.equal(linkEls[2].getAttribute('data-key-nav'), ']');
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/5..10/chell.go');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/5..10/glados.txt');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/5..10/wheatley.md');
    });

    test('prev/up/next links', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: 'PARENT',
        patchNum: '10',
      };
      element._change = {
        revisions: {
          a: {_number: 10},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      flushAsynchronousOperations();
      const linkEls = Polymer.dom(element.root).querySelectorAll('.navLink');
      assert.equal(linkEls.length, 3);
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/10/chell.go');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/10/wheatley.md');
      element._path = 'wheatley.md';
      flushAsynchronousOperations();
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/10/glados.txt');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/');
      assert.isFalse(linkEls[2].hasAttribute('href'));
      element._path = 'chell.go';
      flushAsynchronousOperations();
      assert.isFalse(linkEls[0].hasAttribute('href'));
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/10/glados.txt');
      element._path = 'not_a_real_file';
      flushAsynchronousOperations();
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/10/wheatley.md');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/10/chell.go');
    });

    test('download link', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: 'PARENT',
        patchNum: '10',
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      flushAsynchronousOperations();
      assert.equal(element.$$('.downloadLink').getAttribute('href'),
          '/changes/42/revisions/10/patch?zip&path=glados.txt');
    });

    test('prev/up/next links with patch range', () => {
      element._changeNum = '42';
      element._patchRange = {
        basePatchNum: '5',
        patchNum: '10',
      };
      element._change = {
        revisions: {
          a: {_number: 5},
          b: {_number: 10},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      flushAsynchronousOperations();
      const linkEls = Polymer.dom(element.root).querySelectorAll('.navLink');
      assert.equal(linkEls.length, 3);
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/5..10/chell.go');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/5..10');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/5..10/wheatley.md');
      element._path = 'wheatley.md';
      flushAsynchronousOperations();
      assert.equal(linkEls[0].getAttribute('href'), '/c/42/5..10/glados.txt');
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/5..10');
      assert.isFalse(linkEls[2].hasAttribute('href'));
      element._path = 'chell.go';
      flushAsynchronousOperations();
      assert.isFalse(linkEls[0].hasAttribute('href'));
      assert.equal(linkEls[1].getAttribute('href'), '/c/42/5..10');
      assert.equal(linkEls[2].getAttribute('href'), '/c/42/5..10/glados.txt');
    });

    test('file review status', done => {
      stub('gr-rest-api-interface', {
        getDiffComments() { return Promise.resolve({}); },
      });
      const saveReviewedStub = sandbox.stub(element, '_saveReviewedState',
          () => Promise.resolve());
      sandbox.stub(element.$.diff, 'reload');

      element._loggedIn = true;
      element.params = {
        view: 'gr-diff-view',
        changeNum: '42',
        patchNum: '2',
        basePatchNum: '1',
        path: '/COMMIT_MSG',
      };

      flush(() => {
        const commitMsg = Polymer.dom(element.root).querySelector(
            'input[type="checkbox"]');

        assert.isTrue(commitMsg.checked);
        MockInteractions.tap(commitMsg);
        assert.isFalse(commitMsg.checked);
        assert.isTrue(saveReviewedStub.lastCall.calledWithExactly(false));

        MockInteractions.tap(commitMsg);
        assert.isTrue(commitMsg.checked);
        assert.isTrue(saveReviewedStub.lastCall.calledWithExactly(true));

        done();
      });
    });

    test('diff mode selector correctly toggles the diff', () => {
      const select = element.$.modeSelect;
      const diffDisplay = element.$.diff;
      element._userPrefs = {default_diff_view: 'SIDE_BY_SIDE'};

      // The mode selected in the view state reflects the selected option.
      assert.equal(element._getDiffViewMode(), select.nativeSelect.value);

      // The mode selected in the view state reflects the view rednered in the
      // diff.
      assert.equal(select.nativeSelect.value, diffDisplay.viewMode);

      // We will simulate a user change of the selected mode.
      const newMode = 'UNIFIED_DIFF';
      // Set the actual value of the select, and simulate the change event.
      select.nativeSelect.value = newMode;
      element.fire('change', {}, {node: select.nativeSelect});

      // Make sure the handler was called and the state is still coherent.
      assert.equal(element._getDiffViewMode(), newMode);
      assert.equal(element._getDiffViewMode(), select.nativeSelect.value);
      assert.equal(element._getDiffViewMode(), diffDisplay.viewMode);
    });

    test('diff mode selector initializes from preferences', () => {
      let resolvePrefs;
      const prefsPromise = new Promise(resolve => {
        resolvePrefs = resolve;
      });
      sandbox.stub(element.$.restAPI, 'getPreferences', () => prefsPromise);

      // Attach a new gr-diff-view so we can intercept the preferences fetch.
      const view = document.createElement('gr-diff-view');
      const select = view.$.modeSelect;
      fixture('blank').appendChild(view);
      flushAsynchronousOperations();

      // At this point the diff mode doesn't yet have the user's preference.
      assert.equal(select.nativeSelect.value, 'SIDE_BY_SIDE');

      // Receive the overriding preference.
      resolvePrefs({default_diff_view: 'UNIFIED'});
      flushAsynchronousOperations();
      assert.equal(select.nativeSelect.value, 'SIDE_BY_SIDE');
    });

    test('_loadHash', () => {
      assert.isNotOk(element.$.cursor.initialLineNumber);

      // Ignores invalid hashes:
      element._loadHash('not valid');
      assert.isNotOk(element.$.cursor.initialLineNumber);

      // Revision hash:
      element._loadHash('234');
      assert.equal(element.$.cursor.initialLineNumber, 234);
      assert.equal(element.$.cursor.side, 'right');

      // Base hash:
      element._loadHash('b345');
      assert.equal(element.$.cursor.initialLineNumber, 345);
      assert.equal(element.$.cursor.side, 'left');

      // GWT-style base hash:
      element._loadHash('a123');
      assert.equal(element.$.cursor.initialLineNumber, 123);
      assert.equal(element.$.cursor.side, 'left');
    });

    test('_shortenPath with long path should add ellipsis', () => {
      let path = 'level1/level2/level3/level4/file.js';
      let shortenedPath = util.truncatePath(path);
      // The expected path is truncated with an ellipsis.
      const expectedPath = '\u2026/file.js';
      assert.equal(shortenedPath, expectedPath);

      path = 'level2/file.js';
      shortenedPath = util.truncatePath(path);
      assert.equal(shortenedPath, expectedPath);
    });

    test('_shortenPath with short path should not add ellipsis', () => {
      const path = 'file.js';
      const expectedPath = 'file.js';
      const shortenedPath = util.truncatePath(path);
      assert.equal(shortenedPath, expectedPath);
    });

    test('_onLineSelected', () => {
      const replaceStateStub = sandbox.stub(history, 'replaceState');
      const moveStub = sandbox.stub(element.$.cursor, 'moveToLineNumber');

      const e = {};
      const detail = {number: 123, side: 'right'};

      element._onLineSelected(e, detail);

      assert.isTrue(moveStub.called);
      assert.equal(moveStub.lastCall.args[0], detail.number);
      assert.equal(moveStub.lastCall.args[1], detail.side);

      assert.isTrue(replaceStateStub.called);
    });

    test('_getDiffURL encodes special characters', () => {
      const changeNum = 123;
      const patchRange = {basePatchNum: 123, patchNum: 456};
      const path = 'c++/cpp.cpp';
      assert.equal(element._getDiffURL(changeNum, patchRange, path),
          '/c/123/123..456/c%252B%252B/cpp.cpp');
    });

    test('_getDiffViewMode', () => {
      // No user prefs or change view state set.
      assert.equal(element._getDiffViewMode(), 'SIDE_BY_SIDE');

      // User prefs but no change view state set.
      element._userPrefs = {default_diff_view: 'UNIFIED_DIFF'};
      assert.equal(element._getDiffViewMode(), 'UNIFIED_DIFF');

      // User prefs and change view state set.
      element.changeViewState = {diffMode: 'SIDE_BY_SIDE'};
      assert.equal(element._getDiffViewMode(), 'SIDE_BY_SIDE');
    });

    suite('_loadCommentMap', () => {
      test('empty', done => {
        stub('gr-rest-api-interface', {
          getDiffComments() { return Promise.resolve({}); },
        });
        element._loadCommentMap().then(map => {
          assert.equal(Object.keys(map).length, 0);
          done();
        });
      });

      test('paths in patch range', done => {
        stub('gr-rest-api-interface', {
          getDiffComments() {
            return Promise.resolve({
              'path/to/file/one.cpp': [{patch_set: 3, message: 'lorem'}],
              'path-to/file/two.py': [{patch_set: 5, message: 'ipsum'}],
            });
          },
        });
        element._changeNum = '42';
        element._patchRange = {
          basePatchNum: '3',
          patchNum: '5',
        };
        element._loadCommentMap().then(map => {
          assert.deepEqual(Object.keys(map),
              ['path/to/file/one.cpp', 'path-to/file/two.py']);
          done();
        });
      });

      test('empty for paths outside patch range', done => {
        stub('gr-rest-api-interface', {
          getDiffComments() {
            return Promise.resolve({
              'path/to/file/one.cpp': [{patch_set: 'PARENT', message: 'lorem'}],
              'path-to/file/two.py': [{patch_set: 2, message: 'ipsum'}],
            });
          },
        });
        element._changeNum = '42';
        element._patchRange = {
          basePatchNum: '3',
          patchNum: '5',
        };
        element._loadCommentMap().then(map => {
          assert.equal(Object.keys(map).length, 0);
          done();
        });
      });
    });

    suite('_computeCommentSkips', () => {
      test('empty file list', () => {
        const commentMap = {
          'path/one.jpg': true,
          'path/three.wav': true,
        };
        const path = 'path/two.m4v';
        const fileList = [];
        const result = element._computeCommentSkips(commentMap, fileList, path);
        assert.isNull(result.previous);
        assert.isNull(result.next);
      });

      test('finds skips', () => {
        const fileList = ['path/one.jpg', 'path/two.m4v', 'path/three.wav'];
        let path = fileList[1];
        const commentMap = {};
        commentMap[fileList[0]] = true;
        commentMap[fileList[1]] = false;
        commentMap[fileList[2]] = true;

        let result = element._computeCommentSkips(commentMap, fileList, path);
        assert.equal(result.previous, fileList[0]);
        assert.equal(result.next, fileList[2]);

        commentMap[fileList[1]] = true;

        result = element._computeCommentSkips(commentMap, fileList, path);
        assert.equal(result.previous, fileList[0]);
        assert.equal(result.next, fileList[2]);

        path = fileList[0];

        result = element._computeCommentSkips(commentMap, fileList, path);
        assert.isNull(result.previous);
        assert.equal(result.next, fileList[1]);

        path = fileList[2];

        result = element._computeCommentSkips(commentMap, fileList, path);
        assert.equal(result.previous, fileList[1]);
        assert.isNull(result.next);
      });
    });
  });
</script>