wrote Unit Test for hooks directory

hooks/battery/battery.test.js

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+import 'babel-polyfill';
+import { renderHook, act } from '@testing-library/react-hooks';
+import { useBatteryStatus } from './';
+
+// TODO: addEventListener change trigger mocking
+
+describe('useBatteryStatus', () => {
+  const unsupportMessage = require('./').unsupportMessage; 
+  test(`should return ${unsupportMessage}`, () => {
+    const { result } = renderHook(() => useBatteryStatus());
+
+    expect(result.current.batteryStatus.unsupportMessage).toBe(unsupportMessage);
+  });
+
+  test('should update the batteryStatus state', () => {
+    const { result } = renderHook(() => useBatteryStatus());
+
+    act(() => result.current.updateBatteryStatus({
+      chargingTime: 20,
+      dischargingTime: 40,
+      charging: true,
+      level: 50
+    }));
+
+    expect(result.current.batteryStatus).toEqual({
+      chargingTime: '20 Seconds',
+      dichargeTime: '40 Seconds',
+      level: 50,
+      chargingState: 'Charging'
+    });
+  });
+
+  test('should return mockBattery status', async () => {
+    const originalError = console.error
+    console.error = jest.fn()
+
+    const mockBattery = jest.fn().mockImplementation(() => Promise.resolve({
+      chargingTime: 20,
+      dischargingTime: 40,
+      level: 50,
+      charging: true,
+      addEventListener: jest.fn()
+    }));
+
+    global.navigator.getBattery = mockBattery;
+
+    try {
+      const { result, waitForNextUpdate } = renderHook(() => useBatteryStatus());
+
+      await waitForNextUpdate();
+
+      expect(result.current.batteryStatus).toEqual({
+        chargingTime: '20 Seconds',
+        dichargeTime: '40 Seconds',
+        level: 50,
+        chargingState: 'Charging'
+      });
+    } finally {
+      console.error = originalError;
+    }
+  });
+});

hooks/battery/index.js

@@ -16,7 +16,7 @@
 
 import { useState, useEffect } from 'react';
 
-const unsupportMessage = 'The Battery Status API is not supported on this platform.';
+export const unsupportMessage = 'The Battery Status API is not supported on this platform.';
 
 const useBatteryStatus = () => {
   const [batteryStatus, setBatteryStatus] = useState(null);
@@ -50,7 +50,7 @@ const useBatteryStatus = () => {
   // eslint-disable-next-line
   }, []);
 
-  return batteryStatus;
+  return { batteryStatus, updateBatteryStatus };
 };
 
 export { useBatteryStatus };

hooks/device-class/device-class.test.js

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+import { renderHook } from '@testing-library/react-hooks';
+import { useDeviceClass } from './';
+
+describe('useDeviceClass', () => {
+  test('should return light for Nexus 6', () => {
+    navigator.__defineGetter__('userAgent', () => {
+      return 'Mozilla/5.0 (Linux; Android 5.0; Nexus 6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.136 Mobile Safari/537.36' // customized user agent
+    });
+
+    const { result } = renderHook(() => useDeviceClass());
+
+    expect(result.current).toEqual('light');
+  });
+
+  test('should return heavy for Galaxy 10', () => {
+    navigator.__defineGetter__('userAgent', () => {
+      return 'Mozilla/5.0 (Linux; Android 9; SM-G973F) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.136 Mobile Safari/537.36' // customized user agent
+    });
+
+    const { result } = renderHook(() => useDeviceClass());
+
+    expect(result.current).toEqual('heavy');
+  });
+});

hooks/memory/index.js

@@ -16,11 +16,11 @@
 
 import { useState, useEffect } from 'react';
 
-const unsupportMessage = 'The Memory Status API is not supported on this platform.';
+export const unsupportMessage = 'The Memory Status API is not supported on this platform.';
 
 // Tune these for your application
-const MAX_MEMORY_LIMIT = 50 * 1048576; // 20MB
-const MAX_PERCENT_THRESHOLD = 90;
+export const MAX_MEMORY_LIMIT = 50 * 1048576; // 20MB
+export const MAX_PERCENT_THRESHOLD = 90;
 
 const useMemoryStatus = () => {
   const windowPerformance = window.performance;

hooks/memory/memory.test.js

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+import { renderHook } from '@testing-library/react-hooks';
+import { useMemoryStatus } from './';
+
+describe('useMemoryStatus', () => {
+  const unsupportMessage = require('./').unsupportMessage; 
+  test(`should return ${unsupportMessage}`, () => {
+    const { result } = renderHook(() => useMemoryStatus());
+
+    expect(result.current.unsupportMessage).toBe(unsupportMessage);
+  });
+
+  test('should return mockMemory status', () => {
+    const totalJSHeapSize = 60;
+    const usedJSHeapSize = 40;
+    const jsHeapSizeLimit = 50;
+    global.window.performance.memory = {
+      totalJSHeapSize,
+      usedJSHeapSize,
+      jsHeapSizeLimit
+    };
+
+    const { result } = renderHook(() => useMemoryStatus());
+
+    const MAX_MEMORY_LIMIT = require('./').MAX_MEMORY_LIMIT;
+    const MAX_PERCENT_THRESHOLD = require('./').MAX_PERCENT_THRESHOLD;
+    const overUsedMemorySize = usedJSHeapSize - MAX_MEMORY_LIMIT;
+    const usedMemoryPercent = usedJSHeapSize / jsHeapSizeLimit * 100;
+    const overLoad = overUsedMemorySize > 0 || usedMemoryPercent > MAX_PERCENT_THRESHOLD;
+
+    expect(result.current).toEqual({
+      totalJSHeapSize,
+      usedJSHeapSize,
+      jsHeapSizeLimit,
+      overLoad
+    });
+  });
+});

hooks/network/index.js

@@ -29,16 +29,15 @@ const useEffectiveConnectionType = () => {
   const updateECTStatus = () => {
     setEffectiveConnectionType(getEffectiveConnectionType());
   };
-
+  
   useEffect(() => {
     navigatorConnection && navigatorConnection.addEventListener('change', updateECTStatus);
     return () => {
       navigatorConnection && navigatorConnection.removeEventListener('change', updateECTStatus);
     };
-  // eslint-disable-next-line
   }, []);
 
-  return effectiveConnectionType;
+  return { effectiveConnectionType, updateECTStatus };
 };
 
 export { useEffectiveConnectionType };

hooks/network/network.test.js

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+import { renderHook, act } from '@testing-library/react-hooks';
+import { useEffectiveConnectionType } from './';
+
+// TODO: addEventListener change trigger mocking
+
+describe('useEffectiveConnectionType', () => {
+  test('should return 4g of effectiveConnectionType', () => {
+    global.navigator.connection = {
+      effectiveType: '4g',
+      addEventListener: jest.fn(),
+      removeEventListener: jest.fn()
+    };
+
+    const { result } = renderHook(() => useEffectiveConnectionType());
+
+    expect(result.current.effectiveConnectionType).toEqual('4g');
+  });
+
+  test('should update the effectiveConnectionType state', () => {
+    global.navigator.connection = {
+      effectiveType: '2g',
+      addEventListener: jest.fn(),
+      removeEventListener: jest.fn()
+    };
+
+    const { result } = renderHook(() => useEffectiveConnectionType());
+
+    act(() => result.current.updateECTStatus());
+
+    expect(result.current.effectiveConnectionType).toEqual('2g');
+  });
+});