1 files changed, 98 insertions, 0 deletions
diff --git a/node_modules/shelljs/src/which.js b/node_modules/shelljs/src/which.js
new file mode 100644
index 000000000..03db57bcd
--- /dev/null
+++ b/node_modules/shelljs/src/which.js
@@ -0,0 +1,98 @@
+var common = require('./common');
+var fs = require('fs');
+var path = require('path');
+
+common.register('which', _which, {
+  allowGlobbing: false,
+  cmdOptions: {
+    'a': 'all',
+  },
+});
+
+// XP's system default value for PATHEXT system variable, just in case it's not
+// set on Windows.
+var XP_DEFAULT_PATHEXT = '.com;.exe;.bat;.cmd;.vbs;.vbe;.js;.jse;.wsf;.wsh';
+
+// Cross-platform method for splitting environment PATH variables
+function splitPath(p) {
+  return p ? p.split(path.delimiter) : [];
+}
+
+function checkPath(pathName) {
+  return fs.existsSync(pathName) && !fs.statSync(pathName).isDirectory();
+}
+
+//@
+//@ ### which(command)
+//@
+//@ Examples:
+//@
+//@ ```javascript
+//@ var nodeExec = which('node');
+//@ ```
+//@
+//@ Searches for `command` in the system's PATH. On Windows, this uses the
+//@ `PATHEXT` variable to append the extension if it's not already executable.
+//@ Returns string containing the absolute path to the command.
+function _which(options, cmd) {
+  if (!cmd) common.error('must specify command');
+
+  var pathEnv = process.env.path || process.env.Path || process.env.PATH;
+  var pathArray = splitPath(pathEnv);
+
+  var queryMatches = [];
+
+  // No relative/absolute paths provided?
+  if (cmd.indexOf('/') === -1) {
+    // Assume that there are no extensions to append to queries (this is the
+    // case for unix)
+    var pathExtArray = [''];
+    if (common.platform === 'win') {
+      // In case the PATHEXT variable is somehow not set (e.g.
+      // child_process.spawn with an empty environment), use the XP default.
+      var pathExtEnv = process.env.PATHEXT || XP_DEFAULT_PATHEXT;
+      pathExtArray = splitPath(pathExtEnv.toUpperCase());
+    }
+
+    // Search for command in PATH
+    for (var k = 0; k < pathArray.length; k++) {
+      // already found it
+      if (queryMatches.length > 0 && !options.all) break;
+
+      var attempt = path.resolve(pathArray[k], cmd);
+
+      if (common.platform === 'win') {
+        attempt = attempt.toUpperCase();
+      }
+
+      var match = attempt.match(/\.[^<>:"/\|?*.]+$/);
+      if (match && pathExtArray.indexOf(match[0]) >= 0) { // this is Windows-only
+        // The user typed a query with the file extension, like
+        // `which('node.exe')`
+        if (checkPath(attempt)) {
+          queryMatches.push(attempt);
+          break;
+        }
+      } else { // All-platforms
+        // Cycle through the PATHEXT array, and check each extension
+        // Note: the array is always [''] on Unix
+        for (var i = 0; i < pathExtArray.length; i++) {
+          var ext = pathExtArray[i];
+          var newAttempt = attempt + ext;
+          if (checkPath(newAttempt)) {
+            queryMatches.push(newAttempt);
+            break;
+          }
+        }
+      }
+    }
+  } else if (checkPath(cmd)) { // a valid absolute or relative path
+    queryMatches.push(path.resolve(cmd));
+  }
+
+  if (queryMatches.length > 0) {
+    return options.all ? queryMatches : queryMatches[0];
+  }
+  return options.all ? [] : null;
+}
+module.exports = _which;