feat(generators): add mixin method for symlinking files within `this.…

…destinationRoot()`

lib/generator.js

@@ -4,7 +4,10 @@
 
 'use strict';
 
-var _ = require( 'lodash' );
+var _       = require( 'lodash' )
+,   fsCore  = require( 'fs' )
+,   path    = require( 'path' )
+;
 
 module.exports =
     {
@@ -124,5 +127,45 @@ module.exports =
                 method.apply( fs, args );
             }
         }
+
+    ,
+        /**
+         *  Make a symbolic link within `#destinationRoot()`.
+         *
+         *  @method     _symLink
+         *
+         *  @param      {String}        src         The path relative to `#destinationRoot()` that should become the target of the symbolic link.
+         *  @param      {String}        dst         The path relative to `#destinationRoot()` that should become the symbolic link.
+         *
+         */
+
+        _symLink: function ( src, dst )
+        {
+            src = this.destinationPath( src );
+            dst = this.destinationPath( dst );
+
+            this.conflicter.checkForCollision(
+
+                dst
+            ,   this.read( src )
+            ,   function ( err, status ) {
+
+                    if ( 'identical' === status ) return;
+
+                    //  The symlink may exist, but may link to a nonexistent file in which case `status` will be `'create'`, so try unlinking it anyway.
+                    //
+                    try
+                    {
+                        fsCore.unlinkSync( dst );
+                    }
+                    catch ( error )
+                    {
+                        if ( 'ENOENT' !== error.code  ) throw error;
+                    }
+
+                    fsCore.symlinkSync( path.relative( path.dirname( dst ), src ), dst );
+                }
+            );
+        }
     }
 ;