Add help and version options to build.js.

Former-commit-id: 95a9fdaa7a00550922e71ce01a3f742b845d082c

README.md

@@ -75,23 +75,23 @@ lodash category=collections,functions
 lodash category="collections, functions"
 ~~~
 
- 2. Use the `include` argument to pass the names of methods to include in the build.
+ 2. Use the `exclude` argument to pass the names of methods to exclude from the build.
-~~~ bash
-lodash include=each,filter,map
-lodash include="each, filter, map"
-~~~
-
- 3. Use the `exclude` argument to pass the names of methods to exclude from the build.
 ~~~ bash
 lodash exclude=union,uniq,zip
 lodash exclude="union, uniq, zip"
 ~~~
 
-All arguments, except `include` with `exclude` and `mobile` with `legacy`, may be combined.
+ 3. Use the `include` argument to pass the names of methods to include in the build.
+~~~ bash
+lodash include=each,filter,map
+lodash include="each, filter, map"
+~~~
+
+All arguments, except `exclude` with `include` and `legacy` with `mobile`, may be combined.
 
 ~~~ bash
-lodash backbone mobile category=functions include=pick,uniq
 lodash backbone legacy category=utilities exclude=first,last
+lodash backbone mobile category=functions include=pick,uniq
 ~~~
 
 The `lodash` command-line utility is available when Lo-Dash is installed as a global package (i.e. `npm install -g lodash`).

build.js

@@ -29,7 +29,6 @@
   /** Load customized Lo-Dash module */
   var lodash = (function() {
     var sandbox = {};
-
     if (isLegacy) {
       ['isBindFast', 'isKeysFast', 'nativeBind', 'nativeIsArray', 'nativeKeys'].forEach(function(varName) {
         source = replaceVar(source, varName, 'false');
@@ -261,6 +260,33 @@
 
   /*--------------------------------------------------------------------------*/
 
+  /**
+   * Logs the help message to the console.
+   *
+   * @private
+   */
+  function displayHelp() {
+    console.log([
+      '',
+      '  Commands:',
+      '',
+      '    lodash backbone      Build containing all methods required by Backbone',
+      '    lodash legacy        Build tailored for older browsers without ES5 support',
+      '    lodash mobile        Build with IE < 9 bug fixes and method compilation removed',
+      '    lodash category=...  Comma separated categories of methods to include in the build',
+      '    lodash exclude=...   Comma separated names of methods to exclude from the build',
+      '    lodash include=...   Comma separated names of methods to include in the build',
+      '',
+      '    All arguments, except `exclude` with `include` and `legacy` with `mobile`, may be combined.',
+      '',
+      '  Options:',
+      '',
+      '    -h, --help     Display help information',
+      '    -V, --version  Output current version of Lo-Dash',
+      ''
+    ].join('\n'));
+  }
+
   /**
    * Gets the aliases associated with a given function name.
    *
@@ -537,6 +563,24 @@
 
   /*--------------------------------------------------------------------------*/
 
+  // display help message
+  if (lodash.find(process.argv, function(arg) {
+        return /^(?:-h|--help)$/.test(arg);
+      })) {
+    displayHelp();
+    process.exit();
+  }
+
+  // display `lodash.VERSION`
+  if (lodash.find(process.argv, function(arg) {
+        return /^(?:-V|--version)$/.test(arg);
+      })) {
+    console.log(lodash.VERSION);
+    process.exit();
+  }
+
+  /*--------------------------------------------------------------------------*/
+
   // Backbone build
   if (isBackbone) {
     // add any additional sub-dependencies