testing just execa

Author: bahmutov

__snapshots__/stub-spawn-once-spec.js.snap-shot

@@ -0,0 +1,11 @@
+exports['plain execa.shell 1'] = {
+  "stdout": "hello",
+  "stderr": "",
+  "code": 0,
+  "failed": false,
+  "killed": false,
+  "signal": null,
+  "cmd": "/bin/sh -c echo \"hello\"",
+  "timedOut": false
+}
+

package.json

@@ -69,14 +69,17 @@
     "dependency-check": "2.9.1",
     "deps-ok": "1.2.0",
     "dont-crack": "1.2.1",
+    "execa": "0.7.0",
     "git-issues": "1.3.1",
     "github-post-release": "1.7.1",
     "license-checker": "12.0.0",
     "mocha": "3.4.2",
     "nsp": "2.6.3",
     "pre-git": "3.15.0",
+    "prettier-standard": "6.0.0",
     "semantic-release": "6.3.6",
     "simple-commit-message": "3.1.0",
+    "snap-shot": "2.17.0",
     "standard": "10.0.2"
   },
   "release": {
@@ -86,5 +89,10 @@
       "path": "dont-crack",
       "test-against": []
     }
+  },
+  "dependencies": {
+    "check-more-types": "2.24.0",
+    "debug": "2.6.8",
+    "lazy-ass": "1.6.0"
   }
 }

src/index.js

@@ -1,5 +1,76 @@
 'use strict'
 
+const cp = require('child_process')
+const debug = require('debug')('stub-spawn-once')
+const la = require('lazy-ass')
+const is = require('check-more-types')
 
-module.exports = true
+// save original spawn right away
+const oldSpawn = cp.spawn
 
+function spawnStub (file, args, options) {
+  debug('in spawn stub', file, args)
+
+  const listeners = {}
+  const on = (name, cb) => {
+    if (!listeners[name]) {
+      listeners[name] = []
+    }
+    listeners[name].push(cb)
+  }
+
+  const kill = () => {}
+  const child = {
+    on,
+    kill
+  }
+
+  const exitCode = 0
+  const exitSignal = null
+
+  setTimeout(() => {
+    if (listeners.exit) {
+      listeners.exit.forEach(cb => {
+        console.log('calling exit code %d and signal %s', exitCode, exitSignal)
+        cb(exitCode, exitSignal)
+      })
+    }
+  }, 0)
+
+  return child
+}
+
+// list of stubbed commands
+const commands = {}
+
+function spawnDispatcher (file, args, options) {
+  debug('spawnDispatcher', file, arguments)
+  const command = file + ' ' + args.join(' ')
+  const mock = commands[command]
+  if (mock) {
+    return spawnStub(file, args, options)
+  } else {
+    return oldSpawn(file, args, options)
+  }
+}
+
+function stubbed () {
+  return cp.spawn === spawnDispatcher
+}
+
+if (!stubbed()) {
+  cp.spawn = spawnDispatcher
+} else {
+  debug('child_process.spawn was already stubbed')
+}
+
+function stubSpawnOnce (command, exitCode, stdout, stderr) {
+  la(is.unemptyString(command), 'missing command to stub', command)
+  commands[command] = {
+    exitCode,
+    stdout,
+    stderr
+  }
+}
+
+module.exports = stubSpawnOnce

src/stub-spawn-once-spec.js

@@ -1,11 +1,13 @@
 'use strict'
 
+const execa = require('execa')
+const snapshot = require('snap-shot')
 
 /* global describe, it */
-const stubSpawnOnce = require('.')
+// const stubSpawnOnce = require('.')
 
 describe('stub-spawn-once', () => {
-  it('write this test', () => {
-    console.assert(stubSpawnOnce, 'should export something')
+  it('plain execa.shell', () => {
+    return snapshot(execa.shell('echo "hello"'))
   })
 })