Throw when config already exists

src/index.js

@@ -1,6 +1,16 @@
-const { getConfig, getSampleConfig } = require('./config')
-const { getSampleMigration, runPendingMigrations } = require('./migrations')
-const { mkdir, writeFile } = require('./utils/fs')
+const {
+  findConfig,
+  getConfig,
+  getSampleConfig,
+} = require('./config')
+const {
+  getSampleMigration,
+  runPendingMigrations,
+} = require('./migrations')
+const {
+  mkdir,
+  writeFile,
+} = require('./utils/fs')
 const path = require('path')
 const slugify = require('slugify')
 
@@ -10,8 +20,18 @@ exports.getConfig = getConfig
  * Create a sample configuration in the supplied path
  */
 exports.init = async (targetPath) => {
+  const existingConfigPath = await findConfig()
+    .catch(err => {
+      if (err.code === 'NOCONFIG') return false
+      throw err
+    })
   const sampleConfig = await getSampleConfig()
-  await writeFile(targetPath, sampleConfig)
+  if (existingConfigPath) {
+    const err = new Error(`A configuration already exists in "${existingConfigPath}"`)
+    err.code = 'INITEXISTS'
+    throw err
+  }
+  return writeFile(targetPath, sampleConfig)
 }
 
 /**

src/index.spec.js

@@ -32,12 +32,19 @@ it('can be loaded without throwing exceptions', () => {
 describe('init()', () => {
   it('writes a configtemplate to the supplied path', async () => {
     const targetPath = path.join(process.cwd(), 'exodus-init-test.js')
+    config.findConfig.mockRejectedValueOnce({ code: 'NOCONFIG' })
     config.getSampleConfig.mockResolvedValueOnce('Hello world')
 
     await main.init(targetPath)
 
     expect(fs.writeFile).toHaveBeenCalledWith(targetPath, 'Hello world')
   })
+  it('throws if a configuration already exists', async () => {
+    const targetPath = path.join(process.cwd(), 'exodus-init-test.js')
+    config.findConfig.mockResolvedValueOnce('/interwebz/exodus.config.js')
+
+    await expect(main.init(targetPath)).rejects.toThrow('already exists')
+  })
 })
 
 describe('create()', () => {