Work around quoted batch file names

Fix: #10

Read %~dp0 in a subroutine, so that it does not get an incorrect
value when the command name is quoted.

While we're at it, bring this module up to 100% test coverage,
and fix a few obvious bugs that full coverage uncovered.

BREAKING CHANGE: This requires an update to read-cmd-shim, because the
format of the command invocation changed, and it reads that out of the
generated batch script.

.gitignore

@@ -14,3 +14,5 @@ results
 npm-debug.log
 
 node_modules
+/coverage
+/.nyc_output

index.js

@@ -6,7 +6,7 @@
 // "#!<prog> <args...>"
 //
 // Write a binroot/pkg.bin + ".cmd" file that has this line in it:
-// @<prog> <args...> %~dp0<target> %*
+// @<prog> <args...> %dp0%<target> %*
 
 module.exports = cmdShim
 cmdShim.ifExists = cmdShimIfExists
@@ -43,9 +43,10 @@ function cmdShim (from, to, cb) {
 }
 
 function cmdShim_ (from, to, cb) {
-  var then = times(2, next, cb)
+  var then = times(3, next, cb)
   rm(to, then)
   rm(to + ".cmd", then)
+  rm(to + ".ps1", then)
 
   function next(er) {
     writeShim(from, to, cb)
@@ -61,7 +62,7 @@ function writeShim (from, to, cb) {
     if (er)
       return cb(er)
     fs.readFile(from, "utf8", function (er, data) {
-      if (er) return writeShim_(from, to, null, null, cb)
+      if (er) return writeShim_(from, to, null, null, null, cb)
       var firstLine = data.trim().split(/\r*\n/)[0]
         , shebang = firstLine.match(shebangExpr)
       if (!shebang) return writeShim_(from, to, null, null, null, cb)
@@ -86,50 +87,67 @@ function writeShim_ (from, to, prog, args, variables, cb) {
   args = args || ""
   variables = variables || ""
   if (!prog) {
-    prog = "\"%~dp0\\" + target + "\""
+    prog = "\"%dp0%\\" + target + "\""
     shProg = "\"$basedir/" + shTarget + "\""
     pwshProg = shProg
     args = ""
     target = ""
     shTarget = ""
   } else {
-    longProg = "\"%~dp0\\" + prog + ".exe\""
+    longProg = "\"%dp0%\\" + prog + ".exe\""
     shLongProg = "\"$basedir/" + prog + "\""
     pwshLongProg = "\"$basedir/" + prog + "$exe\""
-    target = "\"%~dp0\\" + target + "\""
+    target = "\"%dp0%\\" + target + "\""
     shTarget = "\"$basedir/" + shTarget + "\""
   }
 
   // @SETLOCAL
+  // @CALL :find_dp0
   //
-  // @IF EXIST "%~dp0\node.exe" (
-  //   @SET "_prog=%~dp0\node.exe"
+  // @IF EXIST "%dp0%\node.exe" (
+  //   @SET "_prog=%dp0%\node.exe"
   // ) ELSE (
   //   @SET "_prog=node"
   //   @SET PATHEXT=%PATHEXT:;.JS;=;%
   // )
   //
-  // "%_prog%" "%~dp0\.\node_modules\npm\bin\npm-cli.js" %*
+  // "%_prog%" "%dp0%\.\node_modules\npm\bin\npm-cli.js" %*
   // @ENDLOCAL
+  // @EXIT /b
+  //
+  // :find_dp0
+  // SET dp0=%~dp0
+  // EXIT /b
+  //
+  // Subroutine trick to fix https://github.com/npm/cmd-shim/issues/10
+  var head = '@ECHO off\r\n' +
+    'SETLOCAL\r\n' +
+    'CALL find_dp0\r\n'
+  var foot = 'ENDLOCAL\r\n' +
+    'EXIT /b\r\n' +
+    'find_dp0:\r\n' +
+    'SET dp0=%~dp0\r\n' +
+    'EXIT /b\r\n'
+
   var cmd
   if (longProg) {
     shLongProg = shLongProg.trim();
     args = args.trim();
     var variableDeclarationsAsBatch = toBatchSyntax.convertToSetCommands(variables)
-    cmd = "@SETLOCAL\r\n"
+    cmd = head
         + variableDeclarationsAsBatch
         + "\r\n"
-        + "@IF EXIST " + longProg + " (\r\n"
-        + "  @SET \"_prog=" + longProg.replace(/(^")|("$)/g, '') + "\"\r\n"
+        + "IF EXIST " + longProg + " (\r\n"
+        + "  SET \"_prog=" + longProg.replace(/(^")|("$)/g, '') + "\"\r\n"
         + ") ELSE (\r\n"
-        + "  @SET \"_prog=" + prog.replace(/(^")|("$)/g, '') + "\"\r\n"
-        + "  @SET PATHEXT=%PATHEXT:;.JS;=;%\r\n"
+        + "  SET \"_prog=" + prog.replace(/(^")|("$)/g, '') + "\"\r\n"
+        + "  SET PATHEXT=%PATHEXT:;.JS;=;%\r\n"
         + ")\r\n"
         + "\r\n"
         +  "\"%_prog%\" " + args + " " + target + " %*\r\n"
-        + '@ENDLOCAL\r\n'
+        + foot
   } else {
-    cmd = "@" + prog + " " + args + " " + target + " %*\r\n"
+    cmd = head + prog + " " + args + " " + target + " %*\r\n" + foot
   }
 
   // #!/bin/sh
@@ -228,7 +246,7 @@ function writeShim_ (from, to, prog, args, variables, cb) {
 }
 
 function chmodShim (to, cb) {
-  var then = times(2, cb, cb)
+  var then = times(3, cb, cb)
   fs.chmod(to, "0755", then)
   fs.chmod(to + ".cmd", "0755", then)
   fs.chmod(to + ".ps1", "0755", then)

lib/to-batch-syntax.js

@@ -36,7 +36,6 @@ function replaceDollarWithPercentPair(value) {
     var dollarExpressions = /\$\{?([^\$@#\?\- \t{}:]+)\}?/g
     var result = ""
     var startIndex = 0
-    value = value || ""
     do {
         var match = dollarExpressions.exec(value)
         if(match) {

package.json

@@ -3,7 +3,8 @@
   "version": "2.1.0",
   "description": "Used in npm for command line application support",
   "scripts": {
-    "test": "tap test/*.js"
+    "test": "tap test/*.js --100",
+    "snap": "TAP_SNAPSHOT=1 tap test/*.js --100"
   },
   "repository": {
     "type": "git",