Grunt: changes as proposed by @tomrake to handle normalized filesSrc parameter

grunt/tasks/grunt-amberc.js

@@ -19,6 +19,9 @@ module.exports = function(grunt) {
          verbose: true                 // optional
        },
        helloWorld: {
+         options: {                             // the 'options' object is optional
+           verbose: true
+         },
          src: ['projects/HelloWorld/st/HelloWorld.st'], // REQUIRED
          output_dir: 'projects/HelloWorld/js',  // optional
          libraries: 'Canvas',                   // optional
@@ -28,18 +31,14 @@ module.exports = function(grunt) {
          amd_namespace: 'MyNamespace',          // optional (default: 'amber')
          main_file: 'myMain.js',                // optional
          output_suffix: 'mySuffix',             // optional
-         library_suffix: '-0.9',                 // optional
-         options: {
-           verbose: true
-         }
+         library_suffix: '-0.9'                 // optional
        },
      },
 
    */
   grunt.registerMultiTask('amberc', 'Compile Smalltalk files with the amberc compiler', function() {
-    // mark required properties
-    this.requiresConfig('amberc.options.amber_dir');
-    this.requiresConfig(['amberc', this.target, 'src']);
+    // mark task as async task
+    var done = this.async();
 
     var options = this.options({
       amber_dir: undefined,
@@ -47,14 +46,18 @@ module.exports = function(grunt) {
     });
     this.data.verbose = options.verbose;
 
-    // mark task as async task
-    var done = this.async();
+    // mark required properties
+    this.requiresConfig('amberc.options.amber_dir');
+    // raise error on missing source files
+    if (this.filesSrc.length === 0) {
+        grunt.fail.fatal('No source files to compile or link.');
+    }
 
     // create and initialize amberc
     var compiler = new amberc.Compiler(grunt.config('amberc.options.amber_dir'));
 
     // generate the amberc configuration out of the given target properties
-    var configuration = generateCompilerConfiguration(this.data, grunt.config('amberc.options.amber_dir'));
+    var configuration = generateCompilerConfiguration(this.data, this.filesSrc, grunt.config('amberc.options.amber_dir'));
 
     // run the compiler and call the async callback once finished
     var self = this;
@@ -65,7 +68,7 @@ module.exports = function(grunt) {
   });
 
 
-  function generateCompilerConfiguration(data, amber_dir) {
+  function generateCompilerConfiguration(data, sourceFiles, amber_dir) {
     var configuration = amberc.createDefaults(amber_dir);
     var parameters = [];
 
@@ -91,7 +94,6 @@ module.exports = function(grunt) {
       configuration.loadsuffix = librarySuffix;
       configuration.suffix_used = librarySuffix;
     }
-    var sourceFiles = data.src;
     if (undefined !== sourceFiles) {
       sourceFiles.forEach(function(currentItem){
         var fileSuffix = path.extname(currentItem);