🧪 #8 Test coverage

src/__tests__/DropZone.spec.tsx

@@ -1,9 +1,9 @@
 import React, { ReactElement } from 'react'
 import '@testing-library/jest-dom'
 import { fireEvent, render, RenderResult, screen } from '@testing-library/react'
-import { DragDropEventOptions, FileType, MessageBoxType } from '../types/types'
+import { DragDropEventOptions, FileType, MessageBoxType, TestFile } from '../types/types'
 import DropZone from '../renderer/main-window/components/DropZone'
-import { mockElectronApi, mockPdfFile, mockTxtFile, noop } from './mocks'
+import { mockDirectory, mockElectronApi, mockFileWithNoType, mockPdfFile, mockTxtFile, noop } from './mocks'
 
 const createDragDropEventOptions = (files: File[]): DragDropEventOptions => ({
   dataTransfer: {
@@ -110,11 +110,35 @@ describe('DropZone', () => {
     expect(messageBoxSpy.mock.calls[0][0]).toEqual(MessageBoxType.ERROR)
   })
 
-  it('should show an error message if drop undesired file type', async () => {
-    const messageBoxSpy = jest.spyOn(window.electron, 'showMessageBox')
-    fireEvent.drop(window, createDragDropEventOptions([mockTxtFile]))
-    await new Promise(process.nextTick) // wait for all code to execute
-    expect(messageBoxSpy).toHaveBeenCalledTimes(1)
-    expect(messageBoxSpy.mock.calls[0][0]).toEqual(MessageBoxType.ERROR)
+  const undesiredFiles: Record<string, TestFile> = {
+    'txt file': {
+      file: mockTxtFile,
+      isFolder: false,
+      fileExtension: '.txt'
+    },
+    directory: {
+      file: mockDirectory,
+      isFolder: true,
+      fileExtension: ''
+    },
+    'file with no type': {
+      file: mockFileWithNoType,
+      isFolder: false,
+      fileExtension: ''
+    }
+  }
+
+  Object.entries(undesiredFiles).forEach(([testFileType, testFile]) => {
+    it(`should show an error message if drop undesired file type (${testFileType})`, async () => {
+      const messageBoxSpy = jest.spyOn(window.electron, 'showMessageBox')
+      jest.spyOn(window.electron, 'fileIsDirectory').mockReturnValue(Promise.resolve(testFile.isFolder))
+      jest.spyOn(window.electron, 'getFileExtension').mockReturnValue(Promise.resolve(testFile.fileExtension))
+
+      fireEvent.drop(window, createDragDropEventOptions([testFile.file]))
+      await new Promise(process.nextTick) // wait for all code to execute
+
+      expect(messageBoxSpy).toHaveBeenCalledTimes(1)
+      expect(messageBoxSpy.mock.calls[0][0]).toEqual(MessageBoxType.ERROR)
+    })
   })
 })

src/__tests__/mocks.tsx

@@ -53,3 +53,5 @@ export const mockTab: Tab = { page: Page.GENERATE, icon: 'mock/icon/path' }
 
 export const mockPdfFile = { ...new File(['Mock PDF File'], 'MockPdfFile.pdf', { type: 'application/pdf' }), path: '/path/to/MockPdfFile.pdf' }
 export const mockTxtFile = { ...new File(['Mock TXT File'], 'MockTxtFile.txt', { type: 'text/plain' }), path: '/path/to/MockTxtFile.txt' }
+export const mockDirectory = { ...new File(['Mock Directory'], 'MockDirectory', {}), path: '/path/to/MockDirectory' }
+export const mockFileWithNoType = { ...new File(['Mock File With No Type'], 'MockFileWithNoTYpe', {}), path: '/path/to/MockFileWithNoTYpe' }

src/renderer/main-window/components/DropZone.tsx

@@ -85,7 +85,7 @@ const DropZone = ({ text, desiredFileType, onDrop }: Props): ReactElement => {
       ? FileType.FOLDER
       : fileExtension === ''
         ? FileType.NO_TYPE
-        : fileExtension.split('.').pop()?.toUpperCase() ?? FileType.UNEXPECTED
+        : fileExtension.split('.').pop()?.toUpperCase() ?? FileType.IMPOSSIBLE
 
     if (fileType !== desiredFileType) {
       const lettersPrecededByAn = 'AEFHILMNORSX'

src/types/types.ts

@@ -47,7 +47,7 @@ export enum FileType {
   PDF = 'PDF',
   FOLDER = 'folder',
   NO_TYPE = 'file with no type',
-  UNEXPECTED = '<unexpected file type>'
+  IMPOSSIBLE = '<impossible file type>'
 }
 
 export enum IpcMainMessage {
@@ -99,3 +99,9 @@ export interface DragDropEventOptions {
     clearData: () => void
   }
 }
+
+export interface TestFile {
+  file: File
+  isFolder: boolean
+  fileExtension: string
+}