diff --git a/static_src/elements/framework/dialogs/mr-issue-hotlists-action/mr-update-issue-hotlists-dialog.test.js b/static_src/elements/framework/dialogs/mr-issue-hotlists-action/mr-update-issue-hotlists-dialog.test.js
new file mode 100644
index 0000000..954b8b9
--- /dev/null
+++ b/static_src/elements/framework/dialogs/mr-issue-hotlists-action/mr-update-issue-hotlists-dialog.test.js
@@ -0,0 +1,193 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import {assert} from 'chai';
+import {MrUpdateIssueDialog} from './mr-update-issue-hotlists-dialog.js';
+import {prpcClient} from 'prpc-client-instance.js';
+
+let element;
+let form;
+
+describe('mr-update-issue-hotlists-dialog', () => {
+  beforeEach(async () => {
+    element = document.createElement('mr-update-issue-hotlists-dialog');
+    document.body.appendChild(element);
+
+    await element.updateComplete;
+    form = element.shadowRoot.querySelector('#issueHotlistsForm');
+
+    sinon.stub(prpcClient, 'call');
+  });
+
+  afterEach(() => {
+    document.body.removeChild(element);
+
+    prpcClient.call.restore();
+  });
+
+  it('initializes', () => {
+    assert.instanceOf(element, MrUpdateIssueDialog);
+  });
+
+  it('no changes', () => {
+    assert.deepEqual(element.changes, {added: [], removed: []});
+  });
+
+  it('clicking on issues produces changes', async () => {
+    element.issueHotlists = [
+      {name: 'Hotlist-1', ownerRef: {userId: 12345}},
+      {name: 'Hotlist-2', ownerRef: {userId: 12345}},
+      {name: 'Hotlist-1', ownerRef: {userId: 67890}},
+    ];
+    element.userHotlists = [
+      {name: 'Hotlist-1', ownerRef: {userId: 67890}},
+      {name: 'Hotlist-2', ownerRef: {userId: 67890}},
+    ];
+    element.user = {userId: 67890};
+
+    element.open();
+    await element.updateComplete;
+
+    const chopsCheckboxes = form.querySelectorAll('chops-checkbox');
+    chopsCheckboxes[0].click();
+    chopsCheckboxes[1].click();
+    assert.deepEqual(element.changes, {
+      added: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+      removed: [{name: 'Hotlist-1', owner: {userId: 67890}}],
+    });
+  });
+
+  it('adding new hotlist produces changes', async () => {
+    await element.updateComplete;
+    form.newHotlistName.value = 'New-Hotlist';
+    assert.deepEqual(element.changes, {
+      added: [],
+      removed: [],
+      created: {
+        name: 'New-Hotlist',
+        summary: 'Hotlist created from issue.',
+      },
+    });
+  });
+
+  it('reset changes', async () => {
+    element.issueHotlists = [
+      {name: 'Hotlist-1', ownerRef: {userId: 12345}},
+      {name: 'Hotlist-2', ownerRef: {userId: 12345}},
+      {name: 'Hotlist-1', ownerRef: {userId: 67890}},
+    ];
+    element.userHotlists = [
+      {name: 'Hotlist-1', ownerRef: {userId: 67890}},
+      {name: 'Hotlist-2', ownerRef: {userId: 67890}},
+    ];
+    element.user = {userId: 67890};
+
+    element.open();
+    await element.updateComplete;
+
+    const chopsCheckboxes = form.querySelectorAll('chops-checkbox');
+    const checkbox1 = chopsCheckboxes[0];
+    const checkbox2 = chopsCheckboxes[1];
+    checkbox1.click();
+    checkbox2.click();
+    form.newHotlisName = 'New-Hotlist';
+    await element.reset();
+    assert.isTrue(checkbox1.checked);
+    assert.isNotTrue(checkbox2.checked); // Falsey property.
+    assert.equal(form.newHotlistName.value, '');
+  });
+
+  it('saving adds issues to hotlist', async () => {
+    sinon.stub(element, 'changes').get(() => ({
+      added: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+    }));
+    element.issueRefs = [{localId: 22, projectName: 'test'}];
+
+    await element.save();
+
+    sinon.assert.calledWith(prpcClient.call, 'monorail.Features',
+        'AddIssuesToHotlists', {
+          hotlistRefs: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+          issueRefs: [{localId: 22, projectName: 'test'}],
+        });
+  });
+
+  it('saving removes issues from hotlist', async () => {
+    sinon.stub(element, 'changes').get(() => ({
+      removed: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+    }));
+    element.issueRefs = [{localId: 22, projectName: 'test'}];
+
+    await element.save();
+
+    sinon.assert.calledWith(prpcClient.call, 'monorail.Features',
+        'RemoveIssuesFromHotlists', {
+          hotlistRefs: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+          issueRefs: [{localId: 22, projectName: 'test'}],
+        });
+  });
+
+  it('saving creates new hotlist with issues', async () => {
+    sinon.stub(element, 'changes').get(() => ({
+      created: {name: 'MyHotlist', summary: 'the best hotlist'},
+    }));
+    element.issueRefs = [{localId: 22, projectName: 'test'}];
+
+    await element.save();
+
+    sinon.assert.calledWith(prpcClient.call, 'monorail.Features',
+        'CreateHotlist', {
+          name: 'MyHotlist',
+          summary: 'the best hotlist',
+          issueRefs: [{localId: 22, projectName: 'test'}],
+        });
+  });
+
+  it('saving refreshes issue hotlises if viewed issue is updated', async () => {
+    sinon.stub(element, 'changes').get(() => ({
+      created: {name: 'MyHotlist', summary: 'the best hotlist'},
+    }));
+    element.issueRefs = [
+      {localId: 22, projectName: 'test'},
+      {localId: 32, projectName: 'test'},
+    ];
+    element.viewedIssueRef = {localId: 32, projectName: 'test'};
+
+    await element.save();
+
+    sinon.assert.calledWith(prpcClient.call, 'monorail.Features',
+        'ListHotlistsByIssue', {issue: {localId: 32, projectName: 'test'}});
+  });
+
+  it('dispatches event upon successfully saving', async () => {
+    sinon.stub(element, 'changes').get(() => ({
+      added: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+    }));
+    element.issueRefs = [{localId: 22, projectName: 'test'}];
+
+    const savedStub = sinon.stub();
+    element.addEventListener('saveSuccess', savedStub);
+
+    await element.save();
+
+    sinon.assert.calledOnce(savedStub);
+  });
+
+  it('dispatches no event upon error saving', async () => {
+    sinon.stub(element, 'changes').get(() => ({
+      added: [{name: 'Hotlist-2', owner: {userId: 67890}}],
+    }));
+    element.issueRefs = [{localId: 22, projectName: 'test'}];
+
+    const error = new Error('Mistakes were made');
+    prpcClient.call.returns(Promise.reject(error));
+
+    const savedStub = sinon.stub();
+    element.addEventListener('saveSuccess', savedStub);
+
+    await element.save();
+
+    sinon.assert.notCalled(savedStub);
+  });
+});