test: replace setup/teardown with functional approach (#199)

test/init.test.js

@@ -7,94 +7,103 @@ import pkg from '../package.json'
 
 const readFile = file => fs.readFile(file, 'utf8')
 
-suite('init', () => {
-  let workDir
-  let originalDir
-
-  const fixturePath = name => path.join(__dirname, 'fixtures', name)
-
-  const fixture = async name => {
-    const src = fixturePath(name)
-    const dest = path.join(workDir, 'package.json')
-    await fs.copy(src, dest)
-    return dest
+const sandbox = async fn => {
+  const workDir = path.join(os.tmpdir(), `${pkg.name}${Date.now()}`)
+  await fs.mkdirs(workDir)
+  const origDir = process.cwd()
+  process.chdir(workDir)
+
+  try {
+    const fixturePath = name => path.join(__dirname, 'fixtures', name)
+    const fixture = async name => {
+      const src = fixturePath(name)
+      const dest = path.join(workDir, 'package.json')
+      await fs.copy(src, dest)
+      return dest
+    }
+    const readFixture = name => readFile(fixturePath(name))
+    const readOrigFile = name => readFile(path.join(origDir, name))
+    const readWorkFile = name => readFile(path.join(workDir, name))
+
+    return await fn({
+      fixturePath,
+      fixture,
+      readFixture,
+      readOrigFile,
+      readWorkFile,
+    })
+  } finally {
+    process.chdir(origDir)
+    await fs.remove(workDir)
   }
+}
 
-  setup('work directory', async () => {
-    workDir = path.join(os.tmpdir(), `${pkg.name}${Date.now()}`)
-    await fs.mkdirs(workDir)
-
-    originalDir = process.cwd()
-    process.chdir(workDir)
-  })
+const testInSandbox = (name, fn) => {
+  test(name, () => sandbox(fn))
+}
 
-  teardown(async () => {
-    process.chdir(originalDir)
-
-    await fs.remove(workDir)
-  })
-
-  test('update "package.json"', async () => {
-    const src = await fixture('package-normal.json')
+suite('init', () => {
+  testInSandbox('update "package.json"', async ctx => {
+    const src = await ctx.fixture('package-normal.json')
     await exec('init')
     const actual = await readFile(src)
-    const expected = await readFile(fixturePath('package-normal_expected.json'))
+    const expected = await ctx.readFixture('package-normal_expected.json')
     assert(actual === expected)
   })
 
-  test('update "package.json" without fields', async () => {
-    const src = await fixture('package-empty.json')
+  testInSandbox('update "package.json" without fields', async ctx => {
+    const src = await ctx.fixture('package-empty.json')
     await exec('init')
     const actual = await readFile(src)
-    const expected = await readFile(fixturePath('package-empty_expected.json'))
+    const expected = await ctx.readFixture('package-empty_expected.json')
     assert(actual === expected)
   })
 
-  test('write ".editorconfig"', async () => {
-    await fixture('package-normal.json')
+  testInSandbox('write ".editorconfig"', async ctx => {
+    await ctx.fixture('package-normal.json')
     const { stdout, stderr } = await exec('init')
     assert(stdout.includes('package.json was updated.'))
     assert(stderr === '')
 
-    const original = await readFile(path.join(originalDir, '.editorconfig'))
-    const copy = await readFile(path.join(workDir, '.editorconfig'))
+    const original = await ctx.readOrigFile('.editorconfig')
+    const copy = await ctx.readWorkFile('.editorconfig')
     assert(original === copy)
   })
 
-  test('write ".prettierignore"', async () => {
-    await fixture('package-normal.json')
+  testInSandbox('write ".prettierignore"', async ctx => {
+    await ctx.fixture('package-normal.json')
     const { stdout, stderr } = await exec('init')
     assert(stdout.includes('package.json was updated.'))
     assert(stderr === '')
 
-    const original = await readFile(path.join(originalDir, '.prettierignore'))
-    const copy = await readFile(path.join(workDir, '.prettierignore'))
+    const original = await ctx.readOrigFile('.prettierignore')
+    const copy = await ctx.readWorkFile('.prettierignore')
     assert(original === copy)
   })
 
-  test('write ".eslintrc.js"', async () => {
-    await fixture('package-normal.json')
+  testInSandbox('write ".eslintrc.js"', async ctx => {
+    await ctx.fixture('package-normal.json')
     const { stdout, stderr } = await exec('init')
     assert(stdout.includes('.eslintrc.js was updated.'))
     assert(stderr === '')
 
-    const actual = await readFile(path.join(workDir, '.eslintrc.js'))
-    const expected = await readFile(fixturePath('.eslintrc_expected.js'))
+    const actual = await ctx.readWorkFile('.eslintrc.js')
+    const expected = await ctx.readFixture('.eslintrc_expected.js')
     assert(actual === expected)
   })
 
-  test('write ".commitlintrc.js"', async () => {
-    await fixture('package-normal.json')
+  testInSandbox('write ".commitlintrc.js"', async ctx => {
+    await ctx.fixture('package-normal.json')
     const { stdout, stderr } = await exec('init')
     assert(stdout.includes('.commitlintrc.js was updated.'))
     assert(stderr === '')
 
-    const actual = await readFile(path.join(workDir, '.commitlintrc.js'))
-    const expected = await readFile(fixturePath('.commitlintrc_expected.js'))
+    const actual = await ctx.readWorkFile('.commitlintrc.js')
+    const expected = await ctx.readFixture('.commitlintrc_expected.js')
     assert(actual === expected)
   })
 
-  test('throw error if no package.json', async () => {
+  testInSandbox('throw error if no package.json', async () => {
     const error = await exec('init').catch(err => err)
     assert(error instanceof Error)
     assert(error.code === 1)