refactor(injection) infer injection args in ng:controller only

Because only controllers don't have currying, we can infer its arguments, all other APIs needing currying, automatic inference complicates the matters unecessary.

Author: mhevery

src/Compiler.js

@@ -40,8 +40,6 @@ Template.prototype = {
 
   addLinkFn:function(linkingFn) {
     if (linkingFn) {
-      if (!linkingFn.$inject)
-        linkingFn.$inject = [];
       this.linkFns.push(linkingFn);
     }
   },

src/Injector.js

@@ -60,14 +60,15 @@ function createInjector(factoryScope, factories, instanceCache) {
     if (!(value in instanceCache)) {
       var factory = factories[value];
       if (!factory) throw Error("Unknown provider for '"+value+"'.");
+      inferInjectionArgs(factory);
       instanceCache[value] = invoke(factoryScope, factory);
     }
     return instanceCache[value];
   }
 
   function invoke(self, fn, args){
     args = args || [];
-    var injectNames = injectionArgs(fn);
+    var injectNames = fn.$inject || [];
     var i = injectNames.length;
     while(i--) {
       args.unshift(injector(injectNames[i]));
@@ -133,7 +134,7 @@ var FN_ARGS = /^function\s*[^\(]*\(([^\)]*)\)/m;
 var FN_ARG_SPLIT = /,/;
 var FN_ARG = /^\s*(.+?)\s*$/;
 var STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/mg;
-function injectionArgs(fn) {
+function inferInjectionArgs(fn) {
   assertArgFn(fn);
   if (!fn.$inject) {
     var args = fn.$inject = [];

src/directives.js

@@ -174,6 +174,7 @@ angularDirective("ng:controller", function(expression){
       getter(scope, expression, true) ||
       getter(window, expression, true);
     assertArgFn(Controller, expression);
+    inferInjectionArgs(Controller);
     return Controller;
   });
   return noop;

test/InjectorSpec.js

@@ -85,11 +85,11 @@ describe('injector', function(){
     it('should return $inject', function(){
       function fn(){}
       fn.$inject = ['a'];
-      expect(injectionArgs(fn)).toBe(fn.$inject);
-      expect(injectionArgs(function(){})).toEqual([]);
-      expect(injectionArgs(function (){})).toEqual([]);
-      expect(injectionArgs(function  (){})).toEqual([]);
-      expect(injectionArgs(function /* */ (){})).toEqual([]);
+      expect(inferInjectionArgs(fn)).toBe(fn.$inject);
+      expect(inferInjectionArgs(function(){})).toEqual([]);
+      expect(inferInjectionArgs(function (){})).toEqual([]);
+      expect(inferInjectionArgs(function  (){})).toEqual([]);
+      expect(inferInjectionArgs(function /* */ (){})).toEqual([]);
     });
 
     it('should create $inject', function(){
@@ -103,28 +103,35 @@ describe('injector', function(){
                  */
           _c,
           /* {some type} */ d){ extraParans();}
-      expect(injectionArgs($f_n0)).toEqual(['$a', 'b_', '_c',  'd']);
+      expect(inferInjectionArgs($f_n0)).toEqual(['$a', 'b_', '_c',  'd']);
       expect($f_n0.$inject).toEqual(['$a', 'b_', '_c',  'd']);
     });
 
     it('should handle no arg functions', function(){
       function $f_n0(){}
-      expect(injectionArgs($f_n0)).toEqual([]);
+      expect(inferInjectionArgs($f_n0)).toEqual([]);
       expect($f_n0.$inject).toEqual([]);
     });
 
     it('should handle args with both $ and _', function(){
       function $f_n0($a_){}
-      expect(injectionArgs($f_n0)).toEqual(['$a_']);
+      expect(inferInjectionArgs($f_n0)).toEqual(['$a_']);
       expect($f_n0.$inject).toEqual(['$a_']);
     });
 
     it('should throw on non function arg', function(){
       expect(function(){
-        injectionArgs({});
+        inferInjectionArgs({});
       }).toThrow();
     });
 
+    it('should infer injection on services', function(){
+      var scope = angular.scope({
+        a: function(){ return 'a';},
+        b: function(a){ return a + 'b';}
+      });
+      expect(scope.$service('b')).toEqual('ab');
+    });
   });
 
   describe('inject', function(){

test/directivesSpec.js

@@ -469,17 +469,21 @@ describe("directive", function() {
       expect(scope.$element.text()).toEqual('hey dude!');
     });
 
+    it('should infer injection arguments', function(){
+      temp.MyController = function($xhr){
+        this.$root.someService = $xhr;
+      };
+      var scope = compile('<div ng:controller="temp.MyController"></div>');
+      expect(scope.someService).toBe(scope.$service('$xhr'));
+    });
   });
 
   describe('ng:cloak', function() {
 
     it('should get removed when an element is compiled', function() {
       var element = jqLite('<div ng:cloak></div>');
-
       expect(element.attr('ng:cloak')).toBe('');
-
       angular.compile(element);
-
       expect(element.attr('ng:cloak')).toBeUndefined();
     });