diff --git a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.ts b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.ts
index e1cc233..77b7717 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.ts
+++ b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.ts
@@ -27,8 +27,9 @@
   AutocompleteSuggestion,
 } from '../../shared/gr-autocomplete/gr-autocomplete';
 import {appContext} from '../../../services/app-context';
+import {GrDialog} from '../../shared/gr-dialog/gr-dialog';
 
-interface RebaseChange {
+export interface RebaseChange {
   name: string;
   value: NumericChangeId;
 }
@@ -39,10 +40,15 @@
 
 export interface GrConfirmRebaseDialog {
   $: {
+    confirmDialog: GrDialog;
     parentInput: GrAutocomplete;
+    parentUpToDateMsg: HTMLDivElement;
+    rebaseOnParent: HTMLDivElement;
     rebaseOnParentInput: HTMLInputElement;
     rebaseOnOtherInput: HTMLInputElement;
+    rebaseOnTip: HTMLDivElement;
     rebaseOnTipInput: HTMLInputElement;
+    tipUpToDateMsg: HTMLDivElement;
   };
 }
 
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.js b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.ts
similarity index 67%
rename from polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.js
rename to polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.ts
index 0faf604..74c1b3c 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.ts
@@ -15,14 +15,18 @@
  * limitations under the License.
  */
 
-import '../../../test/common-test-setup-karma.js';
-import './gr-confirm-rebase-dialog.js';
-import {stubRestApi} from '../../../test/test-utils.js';
+import '../../../test/common-test-setup-karma';
+import './gr-confirm-rebase-dialog';
+import {GrConfirmRebaseDialog, RebaseChange} from './gr-confirm-rebase-dialog';
+import {stubRestApi} from '../../../test/test-utils';
+import * as MockInteractions from '@polymer/iron-test-helpers/mock-interactions';
+import {NumericChangeId} from '../../../types/common';
+import {createChangeViewChange} from '../../../test/test-data-generators';
 
 const basicFixture = fixtureFromElement('gr-confirm-rebase-dialog');
 
 suite('gr-confirm-rebase-dialog tests', () => {
-  let element;
+  let element: GrConfirmRebaseDialog;
 
   setup(() => {
     element = basicFixture.instantiate();
@@ -75,16 +79,20 @@
   test('input cleared on cancel or submit', () => {
     element._text = '123';
     element.$.confirmDialog.dispatchEvent(
-        new CustomEvent('confirm', {
-          composed: true, bubbles: true,
-        }));
+      new CustomEvent('confirm', {
+        composed: true,
+        bubbles: true,
+      })
+    );
     assert.equal(element._text, '');
 
     element._text = '123';
     element.$.confirmDialog.dispatchEvent(
-        new CustomEvent('cancel', {
-          composed: true, bubbles: true,
-        }));
+      new CustomEvent('cancel', {
+        composed: true,
+        bubbles: true,
+      })
+    );
     assert.equal(element._text, '');
   });
 
@@ -102,55 +110,59 @@
   });
 
   suite('parent suggestions', () => {
-    let recentChanges;
-    let getChangesStub;
+    let recentChanges: RebaseChange[];
+    let getChangesStub: sinon.SinonStub;
     setup(() => {
       recentChanges = [
         {
           name: '123: my first awesome change',
-          value: 123,
+          value: 123 as NumericChangeId,
         },
         {
           name: '124: my second awesome change',
-          value: 124,
+          value: 124 as NumericChangeId,
         },
         {
           name: '245: my third awesome change',
-          value: 245,
+          value: 245 as NumericChangeId,
         },
       ];
 
-      getChangesStub = stubRestApi('getChanges').returns(Promise.resolve(
-          [
-            {
-              _number: 123,
-              subject: 'my first awesome change',
-            },
-            {
-              _number: 124,
-              subject: 'my second awesome change',
-            },
-            {
-              _number: 245,
-              subject: 'my third awesome change',
-            },
-          ]
-      ));
+      getChangesStub = stubRestApi('getChanges').returns(
+        Promise.resolve([
+          {
+            ...createChangeViewChange(),
+            _number: 123 as NumericChangeId,
+            subject: 'my first awesome change',
+          },
+          {
+            ...createChangeViewChange(),
+            _number: 124 as NumericChangeId,
+            subject: 'my second awesome change',
+          },
+          {
+            ...createChangeViewChange(),
+            _number: 245 as NumericChangeId,
+            subject: 'my third awesome change',
+          },
+        ])
+      );
     });
 
     test('_getRecentChanges', () => {
-      sinon.spy(element, '_getRecentChanges');
-      return element._getRecentChanges()
-          .then(() => {
-            assert.deepEqual(element._recentChanges, recentChanges);
-            assert.equal(getChangesStub.callCount, 1);
-            // When called a second time, should not re-request recent changes.
-            element._getRecentChanges();
-          })
-          .then(() => {
-            assert.equal(element._getRecentChanges.callCount, 2);
-            assert.equal(getChangesStub.callCount, 1);
-          });
+      const recentChangesSpy = sinon.spy(element, '_getRecentChanges');
+      return element
+        ._getRecentChanges()
+        .then(() => {
+          assert.deepEqual(element._recentChanges, recentChanges);
+          assert.equal(getChangesStub.callCount, 1);
+          // When called a second time, should not re-request recent changes.
+          element._getRecentChanges();
+        })
+        .then(() => {
+          assert.equal(recentChangesSpy.callCount, 2);
+          assert.equal(getChangesStub.callCount, 1);
+        });
     });
 
     test('_filterChanges', () => {
@@ -159,25 +171,25 @@
       assert.equal(element._filterChanges('awesome', recentChanges).length, 3);
       assert.equal(element._filterChanges('third', recentChanges).length, 1);
 
-      element.changeNumber = 123;
+      element.changeNumber = 123 as NumericChangeId;
       assert.equal(element._filterChanges('123', recentChanges).length, 0);
       assert.equal(element._filterChanges('124', recentChanges).length, 1);
       assert.equal(element._filterChanges('awesome', recentChanges).length, 2);
     });
 
     test('input text change triggers function', () => {
-      sinon.spy(element, '_getRecentChanges');
+      const recentChangesSpy = sinon.spy(element, '_getRecentChanges');
       element.$.parentInput.noDebounce = true;
       MockInteractions.pressAndReleaseKeyOn(
-          element.$.parentInput.$.input,
-          13,
-          null,
-          'enter');
+        element.$.parentInput.$.input,
+        13,
+        null,
+        'enter'
+      );
       element._text = '1';
-      assert.isTrue(element._getRecentChanges.calledOnce);
+      assert.isTrue(recentChangesSpy.calledOnce);
       element._text = '12';
-      assert.isTrue(element._getRecentChanges.calledTwice);
+      assert.isTrue(recentChangesSpy.calledTwice);
     });
   });
 });
-