fix: allow backslash (#173)

* add backslash test

* allow escaped backslash through

Author: greggman

src/__tests__/index.js

@@ -133,6 +133,21 @@ it(`should propagate kill signals`, () => {
   expect(crossSpawnMock.__mock.spawned.kill).toHaveBeenCalledWith('SIGBREAK')
 })
 
+it(`should keep backslashes`, () => {
+  isWindowsMock.__mock.returnValue = true
+  crossEnv(['echo', '\\\\\\\\someshare\\\\somefolder'])
+  expect(crossSpawnMock.spawn).toHaveBeenCalledWith(
+    'echo',
+    ['\\\\someshare\\somefolder'],
+    {
+      stdio: 'inherit',
+      env: Object.assign({}, process.env),
+    },
+  )
+  isWindowsMock.__mock.reset()
+})
+
+
 function testEnvSetting(expected, ...envSettings) {
   if (expected.APPDATA === 2) {
     // kill the APPDATA to test both is undefined

src/index.js

@@ -58,9 +58,10 @@ function parseCommand(args) {
         // match "\'" or "'"
         // or match "\" if followed by [$"\] (lookahead)
         .map(a => {
-          const re = /(\\)?'|([\\])(?=[$"\\])/g
+          const re = /\\\\|(\\)?'|([\\])(?=[$"\\])/g
           // Eliminate all matches except for "\'" => "'"
           return a.replace(re, m => {
+            if (m === "\\\\") return "\\"
             if (m === "\\'") return "'"
             return ''
           })