feat(code): allow default exit code 0, close #7

Author: bahmutov

README.md

@@ -61,6 +61,14 @@ execa
   */
 ```
 
+***hint** `exit code` argument is optional and you can omit it (then 0 will be
+returned)
+
+```js
+const { stubSpawnShellOnce } = require('.')
+stubSpawnShellOnce('my command', 'hi there', 'error output string')
+```
+
 [spawn]: http://devdocs.io/node/child_process#child_process_child_process_spawn_command_args_options
 
 ## Install

src/index.js

@@ -111,6 +111,14 @@ if (!stubbed()) {
 
 function stubSpawnOnce (command, exitCode, stdout, stderr) {
   la(is.unemptyString(command), 'missing command to stub', command)
+
+  if (is.string(exitCode)) {
+    debug('stub for %s without explicit exit code, assuming 0', command)
+    stderr = stdout
+    stdout = exitCode
+    exitCode = 0
+  }
+
   commands[command] = {
     exitCode,
     stdout,
@@ -121,6 +129,14 @@ function stubSpawnOnce (command, exitCode, stdout, stderr) {
 // only provide the shell command like 'echo "hello"'
 function stubSpawnShellOnce (command, exitCode, stdout, stderr) {
   la(is.unemptyString(command), 'missing shell command to stub', command)
+
+  if (is.string(exitCode)) {
+    debug('stub for %s without explicit exit code, assuming 0', command)
+    stderr = stdout
+    stdout = exitCode
+    exitCode = 0
+  }
+
   const fullCommand = `/bin/sh -c ${command}`
   commands[fullCommand] = {
     exitCode,

src/stub-spawn-once-spec.js

@@ -65,6 +65,16 @@ describe('stub-spawn-once', () => {
       })
     })
 
+    it('stubs cp.exec output only', done => {
+      const cmd = 'does not exist'
+      stubExecOnce(cmd, 'foo')
+      cp.exec(cmd, (code, stdout) => {
+        la(code === 0, 'wrong code', code)
+        la(stdout === 'foo', 'wrong stdout', stdout)
+        done()
+      })
+    })
+
     it('restores cp.exec after that', done => {
       const cmd = 'does not exist'
       stubExecOnce(cmd, 0, 'foo')