Diagnostics: Breakout diagnostics tests by file

Bug: 1125150
Test: browser_tests --gtest_filter=DiagnosticsApp*
Change-Id: Iac8393f186ce16b126543906b0f3260cf159f14f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2442502
Commit-Queue: Joon Ahn <joonbug@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812908}

chrome/test/data/webui/chromeos/diagnostics/battery_status_card_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+import 'chrome://diagnostics/battery_status_card.js';
+
+import {fakeBatteryChargeStatus, fakeBatteryHealth, fakeBatteryInfo} from 'chrome://diagnostics/fake_data.js';
+import {FakeSystemDataProvider} from 'chrome://diagnostics/fake_system_data_provider.js';
+import {getSystemDataProvider, setSystemDataProviderForTesting} from 'chrome://diagnostics/mojo_interface_provider.js';
+import {flush} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {flushTasks} from 'chrome://test/test_util.m.js';
+import * as diagnostics_test_utils from './diagnostics_test_utils.js';
+
+suite('BatteryStatusCardTest', () => {
+  /** @type {?HTMLElement} */
+  let batteryStatusElement = null;
+
+  /** @type {?FakeSystemDataProvider} */
+  let provider = null;
+
+  suiteSetup(() => {
+    provider = new FakeSystemDataProvider();
+    setSystemDataProviderForTesting(provider);
+  });
+
+  setup(() => {
+    PolymerTest.clearBody();
+  });
+
+  teardown(() => {
+    if (batteryStatusElement) {
+      batteryStatusElement.remove();
+    }
+    batteryStatusElement = null;
+    provider.reset();
+  });
+
+  /**
+   * @param {!BatteryInfo} batteryInfo
+   * @param {!BatteryChargeStatus} batteryChargeStatus
+   * @param {!BatteryHealth} batteryHealth
+   * @return {!Promise}
+   */
+  function initializeBatteryStatusCard(
+      batteryInfo, batteryChargeStatus, batteryHealth) {
+    assertFalse(!!batteryStatusElement);
+
+    // Initialize the fake data.
+    provider.setFakeBatteryChargeStatus(batteryChargeStatus);
+    provider.setFakeBatteryHealth(batteryHealth);
+    provider.setFakeBatteryInfo(batteryInfo);
+
+    // Add the battery status card to the DOM.
+    batteryStatusElement = document.createElement('battery-status-card');
+    assertTrue(!!batteryStatusElement);
+    document.body.appendChild(batteryStatusElement);
+
+    return flushTasks();
+  }
+
+  test('BatteryStatusCardPopulated', () => {
+    return initializeBatteryStatusCard(
+               fakeBatteryInfo, fakeBatteryChargeStatus, fakeBatteryHealth)
+        .then(() => {
+          const dataPoints =
+              diagnostics_test_utils.getDataPointElements(batteryStatusElement);
+          assertEquals(
+              fakeBatteryChargeStatus[0].current_now_milliamps,
+              dataPoints[0].value);
+          assertEquals(
+              fakeBatteryHealth[0].charge_full_design_milliamp_hours,
+              dataPoints[1].value);
+          assertEquals(
+              fakeBatteryChargeStatus[0].charge_full_now_milliamp_hours,
+              dataPoints[2].value);
+          assertEquals(
+              fakeBatteryChargeStatus[0].charge_now_milliamp_hours,
+              dataPoints[3].value);
+          assertEquals(
+              fakeBatteryChargeStatus[0].power_time, dataPoints[4].value);
+          assertEquals(
+              fakeBatteryChargeStatus[0].power_adapter_status,
+              dataPoints[5].value);
+          assertEquals(fakeBatteryHealth[0].cycle_count, dataPoints[6].value);
+
+          const barChart = diagnostics_test_utils.getPercentBarChartElement(
+              batteryStatusElement);
+          assertEquals(
+              fakeBatteryChargeStatus[0].charge_full_now_milliamp_hours,
+              barChart.max);
+          assertEquals(
+              fakeBatteryChargeStatus[0].charge_now_milliamp_hours,
+              barChart.value);
+        });
+  });
+});
\ No newline at end of file

chrome/test/data/webui/chromeos/diagnostics/cpu_card_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+import 'chrome://diagnostics/cpu_card.js';
+
+import {fakeCpuUsage} from 'chrome://diagnostics/fake_data.js';
+import {FakeSystemDataProvider} from 'chrome://diagnostics/fake_system_data_provider.js';
+import {getSystemDataProvider, setSystemDataProviderForTesting} from 'chrome://diagnostics/mojo_interface_provider.js';
+import {flush} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {flushTasks} from 'chrome://test/test_util.m.js';
+import * as diagnostics_test_utils from './diagnostics_test_utils.js';
+
+suite('CpuCardTest', () => {
+  /** @type {?HTMLElement} */
+  let cpuElement = null;
+
+  /** @type {?FakeSystemDataProvider} */
+  let provider = null;
+
+  suiteSetup(() => {
+    provider = new FakeSystemDataProvider();
+    setSystemDataProviderForTesting(provider);
+  });
+
+  setup(() => {
+    PolymerTest.clearBody();
+  });
+
+  teardown(() => {
+    if (cpuElement) {
+      cpuElement.remove();
+    }
+    cpuElement = null;
+    provider.reset();
+  });
+
+  /**
+   * @param {!CpuUsage} cpuUsage
+   * @return {!Promise}
+   */
+  function initializeCpuCard(cpuUsage) {
+    assertFalse(!!cpuElement);
+
+    // Initialize the fake data.
+    provider.setFakeCpuUsage(cpuUsage);
+
+    // Add the CPU card to the DOM.
+    cpuElement = document.createElement('cpu-card');
+    assertTrue(!!cpuElement);
+    document.body.appendChild(cpuElement);
+
+    return flushTasks();
+  }
+
+  test('CpuCardPopulated', () => {
+    return initializeCpuCard(fakeCpuUsage).then(() => {
+      const dataPoints =
+          diagnostics_test_utils.getDataPointElements(cpuElement);
+
+      assertEquals(
+          fakeCpuUsage[0].cpu_temp_degrees_celcius, dataPoints[0].value);
+      assertEquals(fakeCpuUsage[0].percent_usage_user, dataPoints[1].value);
+      assertEquals(fakeCpuUsage[0].percent_usage_system, dataPoints[2].value);
+    });
+  });
+});
\ No newline at end of file

chrome/test/data/webui/chromeos/diagnostics/data_point_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+import 'chrome://diagnostics/data_point.js';
+
+import {flush} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {flushTasks} from 'chrome://test/test_util.m.js';
+
+
+suite('DataPointTest', () => {
+  /** @type {?HTMLElement} */
+  let dataPointElement = null;
+
+  setup(() => {
+    PolymerTest.clearBody();
+  });
+
+  teardown(() => {
+    if (dataPointElement) {
+      dataPointElement.remove();
+    }
+    dataPointElement = null;
+  });
+
+  /**
+   * @param {string} title
+   * @param {string} value
+   */
+  function initializeDataPoint(title, value) {
+    assertFalse(!!dataPointElement);
+
+    // Add the data point to the DOM.
+    dataPointElement = document.createElement('data-point');
+    assertTrue(!!dataPointElement);
+    document.body.appendChild(dataPointElement);
+    dataPointElement.title = title;
+    dataPointElement.value = value;
+    return flushTasks();
+  }
+
+  test('InitializeDataPoint', () => {
+    const title = 'Test title';
+    const value = 'Test value';
+    return initializeDataPoint(title, value).then(() => {
+      assertEquals(title, dataPointElement.$$('.title').textContent.trim());
+      assertEquals(value, dataPointElement.$$('.value').textContent.trim());
+    });
+  });
+});

chrome/test/data/webui/chromeos/diagnostics/diagnostics_app_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+import 'chrome://diagnostics/diagnostics_app.js';
+
+import {flush} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {flushTasks} from 'chrome://test/test_util.m.js';
+
+suite('DiagnosticsAppTest', () => {
+  /** @type {?DiagnosticsApp} */
+  let page = null;
+
+  setup(() => {
+    PolymerTest.clearBody();
+    page = document.createElement('diagnostics-app');
+    assertTrue(!!page);
+    document.body.appendChild(page);
+  });
+
+  teardown(() => {
+    page.remove();
+    page = null;
+  });
+
+  test('LandingPageLoaded', () => {
+    // Verify the overview card is in the page.
+    const overview = page.$$('#overviewCard');
+    assertTrue(!!overview);
+
+    // Verify the memory card is in the page.
+    const memory = page.$$('#memoryCard');
+    assertTrue(!!memory);
+
+    // Verify the CPU card is in the page.
+    const cpu = page.$$('#cpuCard');
+    assertTrue(!!cpu);
+
+    // Verify the battery status card is in the page.
+    const batteryStatus = page.$$('#batteryStatusCard');
+    assertTrue(!!batteryStatus);
+
+    // Verify the session log button is in the page.
+    const sessionLog = page.$$('.session-log-button');
+    assertTrue(!!sessionLog);
+  });
+});

chrome/test/data/webui/chromeos/diagnostics/diagnostics_browsertest.js

@@ -11,11 +11,19 @@ GEN_INCLUDE(['//chrome/test/data/webui/polymer_browser_test_base.js']);
 GEN('#include "chromeos/constants/chromeos_features.h"');
 GEN('#include "content/public/test/browser_test.h"');
 
-[['DiagnosticsApp', 'diagnostics/diagnostics_test.js']].forEach(
-    test => registerTest(...test));
+[['Test', 'diagnostics/diagnostics_app_test.js'],
+ ['CpuCard', 'diagnostics/cpu_card_test.js'],
+ ['DataPoint', 'diagnostics/data_point_test.js'],
+ ['OverviewCard', 'diagnostics/overview_card_test.js'],
+ ['MemoryCard', 'diagnostics/memory_card_test.js'],
+ ['BatteryStatusCard', 'diagnostics/battery_status_card_test.js'],
+ ['FakeObservables', 'diagnostics/fake_observables_test.js'],
+ ['FakeMojoInterface', 'diagnostics/mojo_interface_provider_test.js'],
+ ['FakeMethodProvider', 'diagnostics/fake_method_provider_test.js']]
+    .forEach(test => registerTest(...test));
 
 function registerTest(testName, module) {
-  const className = `${testName}BrowserTest`;
+  const className = `DiagnosticsApp${testName}`;
   this[className] = class extends PolymerTest {
     /** @override */
     get browsePreload() {

chrome/test/data/webui/chromeos/diagnostics/fake_method_provider_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+
+import {FakeMethodResolver} from 'chrome://diagnostics/fake_method_resolver.js';
+
+suite('DiagnosticsFakeMethodResolver', () => {
+  /** @type {?FakeMethodResolver} */
+  let resolver = null;
+
+  setup(() => {
+    resolver = new FakeMethodResolver();
+  });
+
+  teardown(() => {
+    resolver = null;
+  });
+
+  test('AddingMethodNoResult', () => {
+    resolver.register('foo');
+    return resolver.resolveMethod('foo').then((result) => {
+      assertEquals(undefined, result);
+    });
+  });
+
+  test('AddingMethodWithResult', () => {
+    resolver.register('foo');
+    const expected = {'foo': 'bar'};
+    resolver.setResult('foo', expected);
+    return resolver.resolveMethod('foo').then((result) => {
+      assertEquals(expected, result);
+    });
+  });
+
+  test('AddingTwoMethodCallingOne', () => {
+    resolver.register('foo');
+    resolver.register('bar');
+    const expected = {'fooKey': 'fooValue'};
+    resolver.setResult('foo', expected);
+    return resolver.resolveMethod('foo').then((result) => {
+      assertEquals(expected, result);
+    });
+  });
+});

chrome/test/data/webui/chromeos/diagnostics/fake_observables_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+
+import {FakeObservables} from 'chrome://diagnostics/fake_observables.js';
+import {PromiseResolver} from 'chrome://resources/js/promise_resolver.m.js';
+
+suite('FakeObservablesTest', () => {
+  /** @type {?FakeObservables} */
+  let observables = null;
+
+  setup(() => {
+    observables = new FakeObservables();
+  });
+
+  teardown(() => {
+    observables = null;
+  });
+
+  test('RegisterSimpleObservable', () => {
+    observables.register('ObserveFoo_OnFooUpdated');
+    /** @type !Array<string> */
+    const expected = ['bar'];
+    observables.setObservableData('ObserveFoo_OnFooUpdated', expected);
+
+    let resolver = new PromiseResolver();
+    observables.observe('ObserveFoo_OnFooUpdated', (foo) => {
+      assertEquals(expected[0], foo);
+      resolver.resolve();
+    });
+
+    observables.trigger('ObserveFoo_OnFooUpdated');
+    return resolver.promise;
+  });
+
+  test('TwoResults', () => {
+    observables.register('ObserveFoo_OnFooUpdated');
+    /** @type !Array<string> */
+    const expected = ['bar1', 'bar2'];
+    observables.setObservableData('ObserveFoo_OnFooUpdated', expected);
+
+    // The first call will get 'bar1', and the second 'bar2'.
+    let resolver = new PromiseResolver();
+    const expectedCallCount = 2;
+    let callCount = 0;
+    observables.observe('ObserveFoo_OnFooUpdated', (foo) => {
+      assertEquals(expected[callCount % expected.length], foo);
+      callCount++;
+      if (callCount === expectedCallCount) {
+        resolver.resolve();
+      }
+    });
+
+    // Trigger the observer twice.
+    observables.trigger('ObserveFoo_OnFooUpdated');
+    observables.trigger('ObserveFoo_OnFooUpdated');
+    return resolver.promise;
+  });
+
+  test('ObservableDataWraps', () => {
+    observables.register('ObserveFoo_OnFooUpdated');
+    /** @type !Array<string> */
+    const expected = ['bar1', 'bar2'];
+    observables.setObservableData('ObserveFoo_OnFooUpdated', expected);
+
+    // With 3 calls and 2 observable values the response should cycle
+    // 'bar1', 'bar2', 'bar1'
+    let resolver = new PromiseResolver();
+    const expectedCallCount = 3;
+    let callCount = 0;
+    observables.observe('ObserveFoo_OnFooUpdated', (foo) => {
+      assertEquals(expected[callCount % expected.length], foo);
+      callCount++;
+      if (callCount === expectedCallCount) {
+        resolver.resolve();
+      }
+    });
+
+    // Trigger the observer three times.
+    observables.trigger('ObserveFoo_OnFooUpdated');
+    observables.trigger('ObserveFoo_OnFooUpdated');
+    observables.trigger('ObserveFoo_OnFooUpdated');
+    return resolver.promise;
+  });
+});

chrome/test/data/webui/chromeos/diagnostics/fake_system_data_provider_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+
+import {fakeBatteryChargeStatus, fakeBatteryHealth, fakeBatteryInfo, fakeBatteryInfo2, fakeCpuUsage, fakeMemoryUsage} from 'chrome://diagnostics/fake_data.js';
+import {FakeSystemDataProvider} from 'chrome://diagnostics/fake_system_data_provider.js';
+
+suite('FakeSystemDataProviderTest', () => {
+  /** @type {?FakeSystemDataProvider} */
+  let provider = null;
+
+  setup(() => {
+    provider = new FakeSystemDataProvider();
+  });
+
+  teardown(() => {
+    provider = null;
+  });
+
+  test('GetSystemInfo', () => {
+    /** @type {!DeviceCapabilities} */
+    const capabilities = {
+      has_battery: true,
+    };
+
+    /** @type {!VersionInfo} */
+    const version = {
+      milestone_version: 'M97',
+    };
+
+    /** @type {!SystemInfo} */
+    const expected = {
+      board_name: 'BestBoard',
+      cpu_model: 'SuperFast CPU',
+      total_memory_kib: 9999,
+      cores_number: 4,
+      version_info: version,
+      device_capabilities: capabilities,
+    };
+
+    provider.setFakeSystemInfo(expected);
+    return provider.getSystemInfo().then((systemInfo) => {
+      assertDeepEquals(expected, systemInfo);
+    });
+  });
+
+  test('GetBatteryInfo', () => {
+    provider.setFakeBatteryInfo(fakeBatteryInfo);
+    return provider.getBatteryInfo().then((batteryInfo) => {
+      assertDeepEquals(fakeBatteryInfo, batteryInfo);
+    });
+  });
+
+  test('ObserveBatteryHealth', () => {
+    provider.setFakeBatteryHealth(fakeBatteryHealth);
+
+    /** @type {!BatteryHealthObserver} */
+    const batteryHealthObserverRemote = {
+      onBatteryHealthUpdated: (batteryHealth) => {
+        assertDeepEquals(fakeBatteryHealth[0], batteryHealth);
+      }
+    };
+
+    return provider.observeBatteryHealth(batteryHealthObserverRemote);
+  });
+
+  test('ObserveBatteryChargeStatus', () => {
+    provider.setFakeBatteryChargeStatus(fakeBatteryChargeStatus);
+
+    /** @type {!BatteryChargeStatusObserver} */
+    const batteryChargeStatusObserverRemote = {
+      onBatteryChargeStatusUpdated: (batteryChargeStatus) => {
+        assertDeepEquals(fakeBatteryChargeStatus[0], batteryChargeStatus);
+      }
+    };
+
+    return provider.observeBatteryChargeStatus(
+        batteryChargeStatusObserverRemote);
+  });
+
+  test('ObserveCpuUsage', () => {
+    provider.setFakeCpuUsage(fakeCpuUsage);
+
+    /** @type {!CpuUsageObserver} */
+    const cpuObserverRemote = {
+      onCpuUsageUpdated: (cpuUsage) => {
+        assertDeepEquals(fakeCpuUsage[0], cpuUsage);
+      }
+    };
+
+    return provider.observeCpuUsage(cpuObserverRemote);
+  });
+
+  test('ObserveMemoryUsage', () => {
+    provider.setFakeMemoryUsage(fakeMemoryUsage);
+
+    /** @type {!MemoryUsageObserver} */
+    const memoryUsageObserverRemote = {
+      onMemoryUsageUpdated: (memoryUsage) => {
+        assertDeepEquals(fakeMemoryUsage[0], memoryUsage);
+      }
+    };
+
+    return provider.observeMemoryUsage(memoryUsageObserverRemote);
+  });
+
+  test('CallMethodWithNoValue', () => {
+    // Don't set any fake data.
+    return provider.getBatteryInfo().then((value) => {
+      assertEquals(undefined, value);
+    });
+  });
+
+  test('CallMethodDifferentDataAfterReset', () => {
+    // Setup the fake data, but then reset it and set it with new data.
+    provider.setFakeBatteryInfo(fakeBatteryInfo);
+    provider.reset();
+    provider.setFakeBatteryInfo(fakeBatteryInfo2);
+
+    return provider.getBatteryInfo().then((batteryInfo) => {
+      assertDeepEquals(fakeBatteryInfo2, batteryInfo);
+    });
+  });
+
+  test('CallMethodFirstThenDifferentDataAfterReset', () => {
+    // Setup the initial fake data.
+    provider.setFakeBatteryInfo(fakeBatteryInfo);
+    return provider.getBatteryInfo()
+        .then((batteryInfo) => {
+          assertDeepEquals(fakeBatteryInfo, batteryInfo);
+        })
+        .then(() => {
+          // Reset and next time it should fire undefined.
+          provider.reset();
+          return provider.getBatteryInfo().then((value) => {
+            assertEquals(undefined, value);
+          });
+        })
+        .then(() => {
+          // Set different data and next time should fire with it.
+          provider.reset();
+          provider.setFakeBatteryInfo(fakeBatteryInfo2);
+          return provider.getBatteryInfo().then((batteryInfo) => {
+            assertDeepEquals(fakeBatteryInfo2, batteryInfo);
+          });
+        });
+  });
+});
\ No newline at end of file

chrome/test/data/webui/chromeos/diagnostics/memory_card_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+import 'chrome://diagnostics/memory_card.js';
+
+import {fakeMemoryUsage} from 'chrome://diagnostics/fake_data.js';
+import {FakeSystemDataProvider} from 'chrome://diagnostics/fake_system_data_provider.js';
+import {getSystemDataProvider, setSystemDataProviderForTesting} from 'chrome://diagnostics/mojo_interface_provider.js';
+import {flush} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {flushTasks} from 'chrome://test/test_util.m.js';
+import * as diagnostics_test_utils from './diagnostics_test_utils.js';
+
+suite('MemoryCardTest', () => {
+  /** @type {?HTMLElement} */
+  let memoryElement = null;
+
+  /** @type {?FakeSystemDataProvider} */
+  let provider = null;
+
+  suiteSetup(() => {
+    provider = new FakeSystemDataProvider();
+    setSystemDataProviderForTesting(provider);
+  });
+
+  setup(() => {
+    PolymerTest.clearBody();
+  });
+
+  teardown(() => {
+    if (memoryElement) {
+      memoryElement.remove();
+    }
+    memoryElement = null;
+    provider.reset();
+  });
+
+  /**
+   * @param {!MemoryUsage} memoryUsage
+   * @return {!Promise}
+   */
+  function initializeMemoryCard(memoryUsage) {
+    assertFalse(!!memoryElement);
+
+    // Initialize the fake data.
+    provider.setFakeMemoryUsage(memoryUsage);
+
+    // Add the memory card to the DOM.
+    memoryElement = document.createElement('memory-card');
+    assertTrue(!!memoryElement);
+    document.body.appendChild(memoryElement);
+
+    return flushTasks();
+  }
+
+  test('MemoryCardPopulated', () => {
+    return initializeMemoryCard(fakeMemoryUsage).then(() => {
+      const dataPoints =
+          diagnostics_test_utils.getDataPointElements(memoryElement);
+      assertEquals(fakeMemoryUsage[0].total_memory_kib, dataPoints[0].value);
+      assertEquals(
+          fakeMemoryUsage[0].available_memory_kib, dataPoints[1].value);
+      assertEquals(fakeMemoryUsage[0].free_memory_kib, dataPoints[2].value);
+
+      const barChart =
+          diagnostics_test_utils.getPercentBarChartElement(memoryElement);
+      const memInUse = fakeMemoryUsage[0].total_memory_kib -
+          fakeMemoryUsage[0].available_memory_kib;
+      assertEquals(fakeMemoryUsage[0].total_memory_kib, barChart.max);
+      assertEquals(memInUse, barChart.value);
+    });
+  });
+});

chrome/test/data/webui/chromeos/diagnostics/mojo_interface_provider_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+
+import {getSystemDataProvider, setSystemDataProviderForTesting} from 'chrome://diagnostics/mojo_interface_provider.js';
+
+suite('FakeMojoProviderTest', () => {
+  test('SettingGettingTestProvider', () => {
+    // TODO(zentaro): Replace with fake when built.
+    let fake_provider =
+        /** @type {SystemDataProviderInterface} */ (new Object());
+    setSystemDataProviderForTesting(fake_provider);
+    assertEquals(fake_provider, getSystemDataProvider());
+  });
+});
\ No newline at end of file

chrome/test/data/webui/chromeos/diagnostics/overview_card_test.js

+// Copyright 2020 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.
+
+// TODO(jimmyxgong): Use es6 module for mojo binding (crbug/1004256).
+import 'chrome://resources/mojo/mojo/public/js/mojo_bindings_lite.js';
+import 'chrome://diagnostics/overview_card.js';
+
+import {fakeSystemInfo} from 'chrome://diagnostics/fake_data.js';
+import {FakeSystemDataProvider} from 'chrome://diagnostics/fake_system_data_provider.js';
+import {getSystemDataProvider, setSystemDataProviderForTesting} from 'chrome://diagnostics/mojo_interface_provider.js';
+import {flush} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
+import {flushTasks} from 'chrome://test/test_util.m.js';
+
+suite('OverviewCardTest', () => {
+  /** @type {?HTMLElement} */
+  let overviewElement = null;
+
+  /** @type {?FakeSystemDataProvider} */
+  let provider = null;
+
+  suiteSetup(() => {
+    provider = new FakeSystemDataProvider();
+    setSystemDataProviderForTesting(provider);
+  });
+
+  setup(() => {
+    PolymerTest.clearBody();
+  });
+
+  teardown(() => {
+    overviewElement.remove();
+    overviewElement = null;
+    provider.reset();
+  });
+
+  /** @param {!SystemInfo} */
+  function initializeOverviewCard(fakeSystemInfo) {
+    assertFalse(!!overviewElement);
+
+    // Initialize the fake data.
+    provider.setFakeSystemInfo(fakeSystemInfo);
+
+    // Add the overview card to the DOM.
+    overviewElement = document.createElement('overview-card');
+    assertTrue(!!overviewElement);
+    document.body.appendChild(overviewElement);
+
+    return flushTasks();
+  }
+
+  test('OverviewCardPopulated', () => {
+    return initializeOverviewCard(fakeSystemInfo).then(() => {
+      assertEquals(
+          fakeSystemInfo.board_name,
+          overviewElement.$$('#boardName').textContent);
+      assertEquals(
+          fakeSystemInfo.cpu_model_name,
+          overviewElement.$$('#cpuModelName').textContent);
+      assertEquals(
+          fakeSystemInfo.total_memory_kib.toString(),
+          overviewElement.$$('#totalMemory').textContent);
+      assertEquals(
+          fakeSystemInfo.version.milestone_version,
+          overviewElement.$$('#version').textContent);
+    });
+  });
+});
\ No newline at end of file