fix: code was not passed to process.exit

lib/platform-shims/cjs.ts

@@ -27,8 +27,8 @@ export default {
     argv: () => process.argv,
     cwd: process.cwd,
     execPath: () => process.execPath,
-    exit: () => {
-      process.exit()
+    exit: (code: number) => {
+      process.exit(code)
     },
     nextTick: process.nextTick,
     stdColumns: typeof process.stdout.columns !== 'undefined' ? process.stdout.columns : null

test/command.cjs

@@ -619,6 +619,7 @@ describe('Command', () => {
         .commandDir('fixtures/cmddir')
         .parse())
       r.exit.should.equal(true)
+      r.exitCode.should.equal(0)
       r.errors.length.should.equal(0)
       r.should.have.property('logs')
       r.logs.join('\n').split(/\n+/).should.deep.equal([
@@ -1513,6 +1514,7 @@ describe('Command', () => {
         .parse()
     })
     called.should.equal(false)
+    r.exitCode.should.equal(1)
     r.errors.should.match(/Missing required argument/)
   })
 

test/helpers/utils.cjs

@@ -6,6 +6,7 @@ const { format } = require('util')
 // assert against it.
 exports.checkOutput = function checkOutput(f, argv, cb) {
   let exit = false
+  let exitCode = 0
   const _exit = process.exit
   const _emit = process.emit
   const _env = process.env
@@ -14,7 +15,10 @@ exports.checkOutput = function checkOutput(f, argv, cb) {
   const _log = console.log
   const _warn = console.warn
 
-  process.exit = (() => { exit = true })
+  process.exit = ((code) => {
+    exit = true
+    exitCode = code
+  })
   process.env = Hash.merge(process.env, { _: 'node' })
   process.argv = argv || ['./usage']
 
@@ -72,6 +76,7 @@ exports.checkOutput = function checkOutput(f, argv, cb) {
       logs,
       warnings,
       exit,
+      exitCode,
       result
     }
   }