<!DOCTYPE html>
<!--
Copyright (C) 2015 The Android Open Source Project

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->

<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;

    const PARENT = 'PARENT';

    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 = {
        _number: 42,
        revisions: {
          a: {_number: 10},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';
      element.changeViewState.selectedFileIndex = 1;

      const diffNavStub = sandbox.stub(Gerrit.Nav, 'navigateToDiff');
      const changeNavStub = sandbox.stub(Gerrit.Nav, 'navigateToChange');

      MockInteractions.pressAndReleaseKeyOn(element, 85, null, 'u');
      assert(changeNavStub.lastCall.calledWith(element._change),
          'Should navigate to /c/42/');

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

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

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

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(changeNavStub.lastCall.calledWith(element._change),
          '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 = {
        _number: 42,
        revisions: {
          a: {_number: 10},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';

      const diffNavStub = sandbox.stub(Gerrit.Nav, 'navigateToDiff');
      const changeNavStub = sandbox.stub(Gerrit.Nav, 'navigateToChange');

      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(changeNavStub.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(changeNavStub.lastCall.calledWithExactly(element._change, '10',
          '5'), 'Should navigate to /c/42/5..10');

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

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

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

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

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(changeNavStub.lastCall.calledWithExactly(element._change, '10',
          '5'),
          '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 = {
        _number: 42,
        revisions: {
          a: {_number: 1},
          b: {_number: 2},
        },
      };
      element._fileList = ['chell.go', 'glados.txt', 'wheatley.md'];
      element._path = 'glados.txt';

      const diffNavStub = sandbox.stub(Gerrit.Nav, 'navigateToDiff');
      const changeNavStub = sandbox.stub(Gerrit.Nav, 'navigateToChange');

      MockInteractions.pressAndReleaseKeyOn(element, 65, null, 'a');
      assert.isTrue(changeNavStub.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(changeNavStub.lastCall.calledWithExactly(element._change, '1',
          PARENT), 'Should navigate to /c/42/1');

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

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

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

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

      MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
      assert(changeNavStub.lastCall.calledWithExactly(element._change, '1',
          PARENT), '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);
    });

    suite('url params', () => {
      setup(() => {
        sandbox.stub(Gerrit.Nav, 'getUrlForDiff', (c, p, pn, bpn) => {
          return `${c._number}-${p}-${pn}-${bpn}`;
        });
        sandbox.stub(Gerrit.Nav, 'getUrlForChange', (c, pn, bpn) => {
          return `${c._number}-${pn}-${bpn}`;
        });
      });

      test('jump to file dropdown', () => {
        element._changeNum = '42';
        element._patchRange = {
          basePatchNum: PARENT,
          patchNum: '10',
        };
        element._change = {_number: 42};
        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'), '42-chell.go-10-PARENT');
        assert.equal(linkEls[1].getAttribute('href'),
            '42-glados.txt-10-PARENT');
        assert.equal(linkEls[2].getAttribute('href'),
            '42-wheatley.md-10-PARENT');

        assert.equal(element._computeFileDisplayName('/foo/bar/baz'),
            '/foo/bar/baz');
        assert.equal(element._computeFileDisplayName('/foobarbaz'),
            '/foobarbaz');
        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._change = {_number: 42};
        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'), '42-chell.go-10-5');
        assert.equal(linkEls[1].getAttribute('href'), '42-glados.txt-10-5');
        assert.equal(linkEls[2].getAttribute('href'), '42-wheatley.md-10-5');
      });

      test('prev/up/next links', () => {
        element._changeNum = '42';
        element._patchRange = {
          basePatchNum: PARENT,
          patchNum: '10',
        };
        element._change = {
          _number: 42,
          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'), '42-chell.go-10-PARENT');
        assert.equal(linkEls[1].getAttribute('href'), '42-undefined-undefined');
        assert.equal(linkEls[2].getAttribute('href'),
            '42-wheatley.md-10-PARENT');
        element._path = 'wheatley.md';
        flushAsynchronousOperations();
        assert.equal(linkEls[0].getAttribute('href'),
            '42-glados.txt-10-PARENT');
        assert.equal(linkEls[1].getAttribute('href'), '42-undefined-undefined');
        assert.isFalse(linkEls[2].hasAttribute('href'));
        element._path = 'chell.go';
        flushAsynchronousOperations();
        assert.isFalse(linkEls[0].hasAttribute('href'));
        assert.equal(linkEls[1].getAttribute('href'), '42-undefined-undefined');
        assert.equal(linkEls[2].getAttribute('href'),
            '42-glados.txt-10-PARENT');
        element._path = 'not_a_real_file';
        flushAsynchronousOperations();
        assert.equal(linkEls[0].getAttribute('href'),
            '42-wheatley.md-10-PARENT');
        assert.equal(linkEls[1].getAttribute('href'), '42-undefined-undefined');
        assert.equal(linkEls[2].getAttribute('href'), '42-chell.go-10-PARENT');
      });

      test('prev/up/next links with patch range', () => {
        element._changeNum = '42';
        element._patchRange = {
          basePatchNum: '5',
          patchNum: '10',
        };
        element._change = {
          _number: 42,
          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'), '42-chell.go-10-5');
        assert.equal(linkEls[1].getAttribute('href'), '42-10-5');
        assert.equal(linkEls[2].getAttribute('href'), '42-wheatley.md-10-5');
        element._path = 'wheatley.md';
        flushAsynchronousOperations();
        assert.equal(linkEls[0].getAttribute('href'), '42-glados.txt-10-5');
        assert.equal(linkEls[1].getAttribute('href'), '42-10-5');
        assert.isFalse(linkEls[2].hasAttribute('href'));
        element._path = 'chell.go';
        flushAsynchronousOperations();
        assert.isFalse(linkEls[0].hasAttribute('href'));
        assert.equal(linkEls[1].getAttribute('href'), '42-10-5');
        assert.equal(linkEls[2].getAttribute('href'), '42-glados.txt-10-5');
      });
    });

    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('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('hash is determined from parmas', done => {
      stub('gr-rest-api-interface', {
        getDiffComments() { return Promise.resolve({}); },
      });
      sandbox.stub(element.$.diff, 'reload');
      sandbox.stub(element, '_loadHash');

      element._loggedIn = true;
      element.params = {
        view: 'gr-diff-view',
        changeNum: '42',
        patchNum: '2',
        basePatchNum: '1',
        path: '/COMMIT_MSG',
        hash: 10,
      };

      flush(() => {
        assert.isTrue(element._loadHash.lastCall.calledWithExactly(10));
        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);

      // Ignores null hash:
      element._loadHash(null);
      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('_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>