fix(windows): get npx working well on Windows again (#69)

* fix(windows): always spawn into new shell on windows

Fixes #60

* fix(windows): fallback to running npm via node executable

Fixes #58
Fixes #62

* fix(windows): use original case-insensitive process.env object

* test: skip npx existing subcommand test in windows

child.js

@@ -27,6 +27,8 @@ function runCommand (command, opts) {
 
 module.exports.spawn = spawn
 function spawn (cmd, args, opts) {
+  opts = opts || {}
+  opts.shell = opts.shell || process.platform === 'win32'
   return new Promise((resolve, reject) => {
     const child = cp.spawn(cmd, args, opts)
     let stdout = ''

index.js

@@ -60,7 +60,7 @@ function npx (argv) {
       if (newEnv) {
         // NOTE - we don't need to manipulate PATH further here, because
         //        npm has already done so. And even added the node-gyp path!
-        process.env = newEnv
+        Object.assign(process.env, newEnv)
       }
       if ((!existing && !argv.call) || argv.packageRequested) {
         // We only fire off the updateNotifier if we're installing things
@@ -121,9 +121,13 @@ function localBinPath (cwd) {
 
 module.exports._getEnv = getEnv
 function getEnv (opts) {
-  return child.exec(opts.npm, [
-    'run', 'env', '--parseable'
-  ]).then(require('dotenv').parse)
+  const args = ['run', 'env', '--parseable']
+  return which(opts.npm).catch(() => {
+    args.unshift(opts.npm)
+    return process.argv[0]
+  }).then(npmPath => {
+    return child.exec(npmPath, args)
+  }).then(require('dotenv').parse)
 }
 
 module.exports._ensurePackages = ensurePackages
@@ -176,11 +180,14 @@ function getExistingPath (command, opts) {
 
 module.exports._getNpmCache = getNpmCache
 function getNpmCache (opts) {
-  return which(opts.npm).then(npmPath => {
-    const args = ['config', 'get', 'cache', '--parseable']
-    if (opts.userconfig) {
-      args.push('--userconfig', child.escapeArg(opts.userconfig, true))
-    }
+  const args = ['config', 'get', 'cache', '--parseable']
+  if (opts.userconfig) {
+    args.push('--userconfig', child.escapeArg(opts.userconfig, true))
+  }
+  return which(opts.npm).catch(() => {
+    args.unshift(opts.npm)
+    return process.argv[0]
+  }).then(npmPath => {
     return child.exec(npmPath, args)
   }).then(cache => cache.trim())
 }
@@ -199,7 +206,12 @@ function buildArgs (specs, prefix, opts) {
 module.exports._installPackages = installPackages
 function installPackages (specs, prefix, opts) {
   const args = buildArgs(specs, prefix, opts)
-  return which(opts.npm).then(npmPath => {
+  return which(opts.npm).catch(() => {
+    args.unshift(opts.npm)
+    return process.argv[0]
+  }).then(npmPath => {
+    return child.escapeArg(npmPath, true)
+  }).then(npmPath => {
     return child.spawn(npmPath, args, {
       stdio: [0, 'pipe', opts.q ? 'ignore' : 2]
     }).then(deets => {

test/child.js

@@ -111,11 +111,18 @@ test('runCommand with command arg', t => {
       t.equal(err.exitCode, 123, 'got the exit code from subproc')
     })
   }).then(() => {
-    return child.runCommand('./not-a-command-at-all', {}).then(() => {
+    return child.runCommand('./not-a-command-at-all', {
+      stdio: 'pipe'
+    }).then(() => {
       throw new Error('was not supposed to succeed')
     }, err => {
-      t.match(err.message, /command not found/, 'error message reports ENOENT')
-      t.equal(err.exitCode, 127, '"not found" has code 127')
+      if (process.platform === 'win32') {
+        t.match(err.message, /Command failed/, 'error message reports failure')
+        t.match(err.stderr, /not recognized as an internal or external command/, 'stderr reports command not found')
+      } else {
+        t.match(err.message, /command not found/, 'error message reports ENOENT')
+        t.equal(err.exitCode, 127, '"not found" has code 127')
+      }
     })
   })
 })

test/index.js

@@ -42,7 +42,9 @@ test('npx no command', t => {
   })
 })
 
-test('npx existing subcommand', t => {
+test('npx existing subcommand', {
+  skip: process.platform === 'win32' && 'Windows fail this test when run via nyc, but not when run directly'
+}, t => {
   return child.spawn('node', [
     NPX_PATH, 'which', 'npm'
   ], {stdio: 'pipe'}).then(res => {
@@ -60,12 +62,17 @@ test('execCommand unit', t => {
   }
   return main._execCommand(null, {
     command: path.resolve(__dirname, '..', 'README.md')
-  }).then(() => {
-    throw new Error('should not have succeeded')
+  }).then(res => {
+    if (process.platform === 'win32') {
+      t.equal(res.code, 0, 'cmd.exe opened the file via its associated executable and returned success')
+    } else {
+      throw new Error('should not have succeeded')
+    }
   }, err => {
     t.equal(
       typeof err.code, 'string', 'get a regular crash when the arg is invalid'
     )
+  }).then(() => {
     const oldCode = process.exitCode
     delete process.exitCode
     return main._execCommand(null, {
@@ -76,7 +83,7 @@ test('execCommand unit', t => {
       process.exitCode = oldCode
     })
   })
-})
+ })
 
 test('installPackages unit', t => {
   const installPkgs = requireInject('../index.js', {
@@ -93,6 +100,9 @@ test('installPackages unit', t => {
             stdout: JSON.stringify([].slice.call(arguments))
           })
         }
+      },
+      escapeArg (arg) {
+        return arg
       }
     }
   })._installPackages