fix: Use is-windows package for detection (#88)

This commit replaces the vendored `lib/is-windows` module by the `is-windows` package.

- Closes #61

index.js

@@ -7,6 +7,7 @@ const cp = require('child_process')
 const ChildProcess = cp.ChildProcess
 const assert = require('assert')
 const crypto = require('crypto')
+const IS_WINDOWS = require('is-windows')()
 const mkdirp = require('mkdirp')
 const rimraf = require('rimraf')
 const path = require('path')
@@ -34,11 +35,9 @@ const shebang = process.platform === 'os390' ?
 const shim = shebang + process.execPath + '\n' +
   fs.readFileSync(path.join(__dirname, 'shim.js'))
 
-const isWindows = require('./lib/is-windows')()
+const pathRe = IS_WINDOWS ? /^PATH=/i : /^PATH=/
 
-const pathRe = isWindows ? /^PATH=/i : /^PATH=/
-
-const colon = isWindows ? ';' : ':'
+const colon = IS_WINDOWS ? ';' : ':'
 
 function wrap (argv, env, workingDir) {
   const spawnSyncBinding = process.binding('spawn_sync')
@@ -108,7 +107,7 @@ function mungeSh (workingDir, options) {
     options.originalNode = command
     c = match[1] + match[2] + ' "' + workingDir + '/node" ' + match[3]
     options.args[cmdi + 1] = c
-  } else if (exe === 'npm' && !isWindows) {
+  } else if (exe === 'npm' && !IS_WINDOWS) {
     // XXX this will exhibit weird behavior when using /path/to/npm,
     // if some other npm is first in the path.
     const npmPath = whichOrUndefined('npm')
@@ -123,7 +122,7 @@ function mungeSh (workingDir, options) {
 
 function isCmd (file) {
   const comspec = path.basename(process.env.comspec || '').replace(/\.exe$/i, '')
-  return isWindows && (file === comspec || /^cmd(?:\.exe)?$/i.test(file))
+  return IS_WINDOWS && (file === comspec || /^cmd(?:\.exe)?$/i.test(file))
 }
 
 function mungeCmd(workingDir, options) {
@@ -268,7 +267,7 @@ function mungeEnv (workingDir, options) {
     }
   }
   if (pathEnv === undefined) {
-    options.envPairs.push((isWindows ? 'Path=' : 'PATH=') + workingDir)
+    options.envPairs.push((IS_WINDOWS ? 'Path=' : 'PATH=') + workingDir)
   }
   if (options.originalNode) {
     const key = path.basename(workingDir).substr('.node-spawn-wrap-'.length)
@@ -285,7 +284,7 @@ function mungeEnv (workingDir, options) {
 function isnpm (file) {
   // XXX is this even possible/necessary?
   // wouldn't npm just be detected as a node shebang?
-  return file === 'npm' && !isWindows
+  return file === 'npm' && !IS_WINDOWS
 }
 
 function mungenpm (workingDir, options) {
@@ -389,6 +388,7 @@ function setup (argv, env) {
       foregroundChild: require.resolve('foreground-child'),
       signalExit: require.resolve('signal-exit'),
     },
+    isWindows: IS_WINDOWS,
     key: key,
     workingDir: workingDir,
     argv: argv,
@@ -405,7 +405,7 @@ function setup (argv, env) {
 
   mkdirp.sync(workingDir)
   workingDir = fs.realpathSync(workingDir)
-  if (isWindows) {
+  if (IS_WINDOWS) {
     const cmdShim =
       '@echo off\r\n' +
       'SETLOCAL\r\n' +

package.json

@@ -8,6 +8,7 @@
   },
   "dependencies": {
     "foreground-child": "^1.5.6",
+    "is-windows": "^1.0.2",
     "mkdirp": "^0.5.0",
     "os-homedir": "^1.0.1",
     "rimraf": "^2.6.2",
@@ -36,8 +37,7 @@
   },
   "files": [
     "index.js",
-    "shim.js",
-    "lib/is-windows.js"
+    "shim.js"
   ],
   "tap": {
     "coverage": false,

shim.js

@@ -45,6 +45,7 @@
 
   const settings = require('./settings.json')
   const foregroundChild = require(settings.deps.foregroundChild)
+  const IS_WINDOWS = settings.isWindows
   const argv = settings.argv
   const nargs = argv.length
   const env = settings.env
@@ -148,14 +149,7 @@
 
   // Unwrap the PATH environment var so that we're not mucking
   // with the environment.  It'll get re-added if they spawn anything
-  const isWindows = (
-    // TODO: Use `lib/is-windows`
-    process.platform === 'win32' ||
-    process.env.OSTYPE === 'cygwin' ||
-    process.env.OSTYPE === 'msys'
-  )
-
-  if (isWindows) {
+  if (IS_WINDOWS) {
     for (const i in process.env) {
       if (/^path$/i.test(i)) {
         process.env[i] = process.env[i].replace(__dirname + ';', '')

test/basic.js

@@ -1,7 +1,7 @@
 var sw = require('../')
-var isWindows = require('../lib/is-windows.js')()
-var winNoShebang = isWindows && 'no shebang execution on windows'
-var winNoSig = isWindows && 'no signals get through cmd'
+var IS_WINDOWS = require('is-windows')()
+var winNoShebang = IS_WINDOWS && 'no shebang execution on windows'
+var winNoSig = IS_WINDOWS && 'no signals get through cmd'
 
 var onExit = require('signal-exit')
 var cp = require('child_process')
@@ -196,7 +196,7 @@ t.test('exec execPath', function (t) {
   t.plan(4)
 
   t.test('basic', function (t) {
-    var opt = isWindows ? null : { shell: '/bin/bash' }
+    var opt = IS_WINDOWS ? null : { shell: '/bin/bash' }
     var child = cp.exec('"' + process.execPath + '" "' + fixture + '" xyz', opt)
 
     var out = ''
@@ -212,7 +212,7 @@ t.test('exec execPath', function (t) {
   })
 
   t.test('execPath wrapped with quotes', function (t) {
-    var opt = isWindows ? null : { shell: '/bin/bash' }
+    var opt = IS_WINDOWS ? null : { shell: '/bin/bash' }
     var child = cp.exec(JSON.stringify(process.execPath) + ' ' + fixture +
       ' xyz', opt)