From a2df99d92aca7d30c912abab1757718757f364e2 Mon Sep 17 00:00:00 2001
From: Remi <remi.d45@gmail.com>
Date: Tue, 20 Oct 2020 14:55:26 +0200
Subject: [PATCH] test(cli): use mock-fs in removePlugin

---
 .../remove-plugin/removePlugin.test.ts        | 163 +++++++++++-------
 1 file changed, 103 insertions(+), 60 deletions(-)

diff --git a/packages/cli/src/commands/remove-plugin/removePlugin.test.ts b/packages/cli/src/commands/remove-plugin/removePlugin.test.ts
index 6433cb6116..3ef9cd113f 100644
--- a/packages/cli/src/commands/remove-plugin/removePlugin.test.ts
+++ b/packages/cli/src/commands/remove-plugin/removePlugin.test.ts
@@ -31,6 +31,7 @@ import {
   removeSymLink,
   removePluginFromCodeOwners,
 } from './removePlugin';
+import mockFs from 'mock-fs';
 
 const BACKSTAGE = `@backstage`;
 const testPluginName = 'yarn-test-package';
@@ -47,13 +48,24 @@ const createTestPackageFile = async (
   // Copy contents of package file for test
   const packageFileContent = JSON.parse(fse.readFileSync(packageFile, 'utf8'));
 
-  packageFileContent.dependencies[testPluginPackage] = '0.1.0';
-  fse.createFileSync(testFilePath);
-  fse.writeFileSync(
-    testFilePath,
-    `${JSON.stringify(packageFileContent, null, 2)}\n`,
-    'utf8',
-  );
+  const testFileContent = {
+    ...packageFileContent,
+    dependencies: {
+      ...packageFileContent.dependencies,
+      [testPluginPackage]: '0.1.0',
+    },
+  };
+
+  mockFs({
+    '/packages': {
+      app: {
+        'package.json': `${JSON.stringify(packageFileContent, null, 2)}\n`,
+      },
+    },
+    '/remove-plugin-test': {
+      [testFilePath]: `${JSON.stringify(testFileContent, null, 2)}\n`,
+    },
+  });
   return;
 };
 
@@ -62,21 +74,47 @@ const createTestPluginFile = async (
   pluginsFilePath: string,
 ) => {
   // Copy contents of package file for test
-  fse.copyFileSync(pluginsFilePath, testFilePath);
+  const pluginsFileContent = fse.readFileSync(pluginsFilePath);
+
+  mockFs({
+    '/remove-plugin-test': {
+      [testFilePath]: `${pluginsFileContent}\n`,
+      [pluginsFilePath]: `${pluginsFileContent}\n`,
+    },
+    '/packages': {
+      app: {
+        src: {
+          'plugin.ts': `${pluginsFileContent}\n`,
+        },
+      },
+    },
+  });
+
   const pluginNameCapitalized = testPluginName
     .split('-')
     .map(name => capitalize(name))
     .join('');
-  const exportStatement = `export { plugin as ${pluginNameCapitalized}} from @backstage/plugin-${testPluginName}`;
-  await addExportStatement(testFilePath, exportStatement);
+  const exportStatement = `export { default as ${pluginNameCapitalized}} from @backstage/plugin-${testPluginName}`;
+  addExportStatement(`/remove-plugin-test/${testFilePath}`, exportStatement);
 };
 
 const mkTestPluginDir = (testDirPath: string) => {
-  fse.mkdirSync(testDirPath);
-  for (let i = 0; i < 50; i++)
-    fse.createFileSync(path.join(testDirPath, `testFile${i}.ts`));
+  const dirPath = `/${testDirPath}`;
+
+  const pluginFiles: { [index: number]: string } = {};
+  for (let i = 0; i < 50; i++) {
+    pluginFiles[i] = '';
+  }
+
+  mockFs({
+    [dirPath]: pluginFiles,
+  });
 };
 
+afterEach(() => {
+  mockFs.restore();
+});
+
 describe('removePlugin', () => {
   beforeAll(() => {
     // Create temporary directory for all tests
@@ -95,60 +133,65 @@ describe('removePlugin', () => {
     it('removes plugin references from /packages/app/package.json', async () => {
       // Set up test
       const packageFilePath = path.join(appPath, 'package.json');
-      const testFilePath = path.join(tempDir, 'test.json');
+      const testFilePath = 'test.json';
       createTestPackageFile(testFilePath, packageFilePath);
-      try {
-        await removeReferencesFromAppPackage(testFilePath, testPluginName);
-        const testFileContent = removeEmptyLines(
-          fse.readFileSync(testFilePath, 'utf8'),
-        );
-        const packageFileContent = removeEmptyLines(
-          fse.readFileSync(packageFilePath, 'utf8'),
-        );
-        expect(testFileContent).toBe(packageFileContent);
-      } finally {
-        fse.removeSync(testFilePath);
-      }
-    });
+      await removeReferencesFromAppPackage(
+        '/remove-plugin-test/test.json',
+        testPluginName,
+      );
+      const testFileContent = removeEmptyLines(
+        fse.readFileSync(`/remove-plugin-test/${testFilePath}`, 'utf8'),
+      );
 
-    it('removes plugin exports from /packages/app/src/package.json', async () => {
-      const testFilePath = path.join(tempDir, 'test.ts');
+      const packageFileContent = removeEmptyLines(
+        fse.readFileSync('/packages/app/package.json', 'utf8'),
+      );
+      expect(testFileContent).toBe(packageFileContent);
+    });
+    it('removes plugin exports from /packages/app/src/packacge.json', async () => {
+      const testFilePath = 'test.ts';
       const pluginsFilePaths = path.join(appPath, 'src', 'plugins.ts');
-      await createTestPluginFile(testFilePath, pluginsFilePaths);
-      try {
-        await removeReferencesFromPluginsFile(testFilePath, testPluginName);
-        const testFileContent = removeEmptyLines(
-          fse.readFileSync(testFilePath, 'utf8'),
-        );
-        const pluginsFileContent = removeEmptyLines(
-          fse.readFileSync(pluginsFilePaths, 'utf8'),
-        );
-        expect(testFileContent).toBe(pluginsFileContent);
-      } finally {
-        fse.removeSync(testFilePath);
-      }
+      createTestPluginFile(testFilePath, pluginsFilePaths);
+      await removeReferencesFromPluginsFile(
+        `/remove-plugin-test/${testFilePath}`,
+        testPluginName,
+      );
+      const testFileContent = removeEmptyLines(
+        fse.readFileSync(`/remove-plugin-test/${testFilePath}`, 'utf8'),
+      );
+      const pluginsFileContent = removeEmptyLines(
+        fse.readFileSync('/packages/app/src/plugin.ts', 'utf8'),
+      );
+      expect(testFileContent).toBe(pluginsFileContent);
     });
 
     it('removes codeOwners references', async () => {
-      const testFilePath = path.join(tempDir, 'test');
+      const testFileName = 'test';
+      const testFilePath = `/remove-plugin-test/${testFileName}`;
       const codeownersPath = path.join(githubDir, 'CODEOWNERS');
-      try {
-        fse.copySync(codeownersPath, testFilePath);
-        const testFileContent = removeEmptyLines(
-          fse.readFileSync(testFilePath, 'utf8'),
-        );
-        const codeOwnersFileContent = removeEmptyLines(
-          fse.readFileSync(codeownersPath, 'utf8'),
-        );
-        await addCodeownersEntry(testFilePath!, `/plugins/${testPluginName}`, [
-          '@thisIsAtestTeam',
-          'test@gmail.com',
-        ]);
-        await removePluginFromCodeOwners(testFilePath, testPluginName);
-        expect(testFileContent).toBe(codeOwnersFileContent);
-      } finally {
-        if (fse.existsSync(testFilePath)) fse.removeSync(testFilePath);
-      }
+      const mockedCodeownersPath = '/.github/CODEOWNERS';
+
+      mockFs({
+        '/remove-plugin-test': {
+          [testFileName]: '',
+        },
+        '/.github': {
+          CODEOWNERS: fse.readFileSync(codeownersPath),
+        },
+      });
+      fse.copySync(mockedCodeownersPath, testFilePath);
+      const testFileContent = removeEmptyLines(
+        fse.readFileSync(testFilePath, 'utf8'),
+      );
+      const codeOwnersFileContent = removeEmptyLines(
+        fse.readFileSync(mockedCodeownersPath, 'utf8'),
+      );
+      await addCodeownersEntry(testFilePath!, `/plugins/${testPluginName}`, [
+        '@thisIsAtestTeam',
+        'test@gmail.com',
+      ]);
+      await removePluginFromCodeOwners(testFilePath, testPluginName);
+      expect(testFileContent).toBe(codeOwnersFileContent);
     });
   });