test: improve test coverage

Author: mnightingale

tests/CacheableImage.test.tsx

@@ -106,6 +106,22 @@ describe('CacheableImage', function () {
       expect(MockedRNFS.copyFile).toHaveBeenCalled()
     })
 
+    it('When local file exists but it fails to be copied to the cache.', async () => {
+      MockedRNFS.copyFile.mockRejectedValueOnce(new Error('Copy failed'))
+
+      const CacheableImage = imageCacheHoc(Image)
+
+      const local = '/exists.png'
+      const url = 'https://example.com/exists.png'
+
+      const result = await CacheableImage.cacheLocalFile(local, url)
+
+      expect(result).toStrictEqual({
+        url: 'https://example.com/exists.png',
+        path: null,
+      })
+    })
+
     it('When local file exists, it should be moved to the cache', async () => {
       const CacheableImage = imageCacheHoc(Image)
 
@@ -166,6 +182,33 @@ describe('CacheableImage', function () {
         },
       )
     })
+
+    it('When local file and observable exist, it should be notified of changes even if hash fails.', async (done) => {
+      MockedRNFS.hash.mockRejectedValueOnce(new Error('File not found.'))
+
+      FileSystem.cacheObservables[
+        '90c1be491d18ff2a7280039e9b65749461a65403.png'
+      ] = new ReplaySubject<CacheFileInfo>(1)
+
+      const CacheableImage = imageCacheHoc(Image)
+
+      const local = '/exists.png'
+      const url = 'https://example.com/exists.png'
+
+      await CacheableImage.cacheLocalFile(local, url)
+
+      FileSystem.cacheObservables['90c1be491d18ff2a7280039e9b65749461a65403.png'].subscribe(
+        (value) => {
+          expect(value).toStrictEqual({
+            path:
+              'file:///base/file/path/react-native-image-cache-hoc/90c1be491d18ff2a7280039e9b65749461a65403.png',
+            fileName: '90c1be491d18ff2a7280039e9b65749461a65403.png',
+            md5: undefined, // Hash failed
+          })
+          done()
+        },
+      )
+    })
   })
 
   it('#flush static method should work as expected.', () => {
@@ -318,6 +361,58 @@ describe('CacheableImage', function () {
     })
   })
 
+  it('componentDidUpdate should validate the source prop correctly.', (done) => {
+    console.warn = jest.fn()
+
+    const CacheableImage = imageCacheHoc(Image)
+
+    const wrapper = shallow(<CacheableImage {...mockData.mockCacheableImageProps} />)
+
+    setImmediate(() => {
+      expect(wrapper.prop('source')).toBeDefined()
+
+      // Update to an invalid uri
+      wrapper.setProps({ source: { uri: './local-file.jpg' } })
+
+      setImmediate(() => {
+        expect(console.warn).toHaveBeenNthCalledWith(
+          1,
+          'Invalid source prop. <CacheableImage> props.source.uri should be a web accessible url with a valid protocol and host. NOTE: Default valid protocol is https, default valid hosts are *.',
+        )
+
+        expect(wrapper.prop('source')).toBeUndefined()
+
+        done()
+      })
+    })
+  })
+
+  it('componentDidUpdate should allow file protocol.', (done) => {
+    console.warn = jest.fn()
+
+    const CacheableImage = imageCacheHoc(Image)
+
+    const wrapper = shallow(<CacheableImage {...mockData.mockCacheableImageProps} />)
+
+    setImmediate(() => {
+      expect(wrapper.prop('source')).toBeDefined()
+
+      // Update to a local file uri
+      wrapper.setProps({ source: { uri: 'file:///local-file.jpg' } })
+
+      setImmediate(() => {
+        expect(console.warn).toHaveBeenNthCalledWith(
+          1,
+          'Invalid source prop. <CacheableImage> props.source.uri should be a web accessible url with a valid protocol and host. NOTE: Default valid protocol is https, default valid hosts are *.',
+        )
+
+        expect(wrapper.prop('source')).toHaveProperty('uri', 'file:///local-file.jpg')
+
+        done()
+      })
+    })
+  })
+
   it('#render with valid props does not throw an error.', (done) => {
     const CacheableImage = imageCacheHoc(Image)
 

tests/FileSystem.test.tsx

@@ -3,8 +3,10 @@ import pathLib from 'path'
 import { mockData } from './mockData'
 import RNFS from 'react-native-fs'
 import uuid from 'react-native-uuid'
-import FileSystemFactory, { FileSystem } from '../src/FileSystem'
+import FileSystemFactory, { CacheFileInfo, FileSystem } from '../src/FileSystem'
 import { mocked } from 'ts-jest/utils'
+import { ReplaySubject } from 'rxjs'
+import composeDownloadFile from './utilities/composeDownloadFile'
 
 describe('FileSystem', function () {
   const MockedRNFS = mocked(RNFS, true)
@@ -438,6 +440,59 @@ describe('FileSystem', function () {
         },
       })
     })
+
+    it('#observable should handle rejection.', (done) => {
+      const fileSystem = FileSystemFactory()
+
+      MockedRNFS.hash
+        // existing
+        .mockRejectedValueOnce(new Error('File not found.'))
+
+      MockedRNFS.downloadFile.mockImplementationOnce(() => ({
+        jobId: -1,
+        promise: Promise.reject(new Error('Internal')),
+      }))
+
+      const url =
+        'https://img.wennermedia.com/5333a62d-07db-432a-92e2-198cafa38a14-326adb1a-d8ed-4a5d-b37e-5c88883e1989.png'
+
+      fileSystem.fetchFile(url).subscribe({
+        next: (element) => {
+          expect(element).toStrictEqual({
+            path: null,
+            fileName: 'cd7d2199cd8e088cdfd9c99fc6359666adc36289.png',
+          })
+
+          done()
+        },
+      })
+    })
+
+    it('#observable should use ETag header on download.', (done) => {
+      const fileSystem = FileSystemFactory()
+
+      MockedRNFS.hash.mockRejectedValueOnce(new Error('File not found.'))
+
+      MockedRNFS.downloadFile.mockImplementationOnce(
+        composeDownloadFile({
+          headers: {
+            ETag: 'foobar',
+          },
+        }),
+      )
+
+      fileSystem
+        .fetchFile(
+          'https://img.wennermedia.com/5333a62d-07db-432a-92e2-198cafa38a14-326adb1a-d8ed-4a5d-b37e-5c88883e1989.png',
+        )
+        .subscribe({
+          next: (element) => {
+            expect(element).toHaveProperty('md5', 'foobar')
+
+            done()
+          },
+        })
+    })
   })
 
   describe('fetchFile', () => {
@@ -529,5 +584,26 @@ describe('FileSystem', function () {
 
       return expect(fileSystem.unlink(invalidPath)).resolves.toEqual(true)
     })
+
+    it('#unlink should be notify subscribers of changes', async (done) => {
+      const fileSystem = FileSystemFactory()
+
+      const url = 'https://example.com/exists.png'
+      const fileName = fileSystem.getFileNameFromUrl(url)
+
+      FileSystem.cacheObservables[fileName] = new ReplaySubject<CacheFileInfo>(1)
+
+      expect(fileSystem.unlink(fileName)).resolves.toEqual(true)
+
+      FileSystem.cacheObservables['90c1be491d18ff2a7280039e9b65749461a65403.png'].subscribe(
+        (value) => {
+          expect(value).toStrictEqual({
+            path: null,
+            fileName,
+          })
+          done()
+        },
+      )
+    })
   })
 })

tests/__mocks__/react-native-fs.tsx

@@ -1,5 +1,6 @@
-import { ReadDirItem } from 'react-native-fs'
+import { ReadDirItem, DownloadFileOptions, DownloadResult } from 'react-native-fs'
 import { mockData } from '../mockData'
+import composeDownloadFile from '../utilities/composeDownloadFile'
 
 const readDir = jest.fn<Promise<ReadDirItem[]>, any[]>().mockResolvedValue([
   {
@@ -86,9 +87,13 @@ module.exports = {
   writeFile: jest.fn(),
   appendFile: jest.fn(),
   write: jest.fn(),
-  downloadFile: jest.fn(() => ({
-    promise: Promise.resolve({ statusCode: 200 }),
-  })),
+  downloadFile: jest
+    .fn<{ jobId: number; promise: Promise<DownloadResult> }, DownloadFileOptions[]>()
+    .mockImplementation(
+      composeDownloadFile({
+        statusCode: 200,
+      }),
+    ),
   uploadFiles: jest.fn(),
   touch: jest.fn(),
   MainBundlePath: jest.fn(),

tests/imageCacheHoc.test.tsx

@@ -89,4 +89,20 @@ describe('CacheableImage', function () {
 
     expect(wrapper).toMatchSnapshot()
   })
+
+  it('renders file protocol correctly.', (done) => {
+    console.warn = jest.fn()
+
+    const CacheableImage = imageCacheHoc(Image)
+
+    const wrapper = shallow(<CacheableImage source={{ uri: 'file:///exists.jpg' }} />)
+
+    setImmediate(() => {
+      expect(wrapper.prop('source')).toStrictEqual({
+        uri: 'file:///exists.jpg',
+      })
+
+      done()
+    })
+  })
 })

tests/utilities/composeDownloadFile.ts

@@ -0,0 +1,23 @@
+import RNFS from 'react-native-fs'
+
+export default ({
+  statusCode = 200,
+  headers = {},
+}: {
+  statusCode?: number
+  headers?: RNFS.Headers
+}) => (options: RNFS.DownloadFileOptions) => {
+  if (options.begin !== undefined && statusCode >= 200 && statusCode < 300) {
+    options.begin({
+      jobId: -1,
+      statusCode,
+      contentLength: 1,
+      headers,
+    })
+  }
+
+  return {
+    jobId: -1,
+    promise: Promise.resolve({ jobId: -1, statusCode, bytesWritten: 1 }),
+  }
+}