feat(angular.bootstrap): support deferred bootstrap

This features enables tools like Batarang and test runners to hook into angular's bootstrap process and sneak in more modules into the DI registry which can replace or augment DI services for the purpose of instrumentation or mocking out heavy dependencies. If window.name contains prefix NG_DEFER_BOOTSTRAP! when angular.bootstrap is called, the bootstrap process will be paused until angular.resumeBootstrap is called. angular.resumeBootstrap takes an optional array of modules that should be added to the original list of modules that the app was about to be bootstrapped with.
angular · Mar 7, 2013 · 603fe0d · 603fe0d
1 parent 485f104
commit 603fe0d
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Showing 2 changed files with 106 additions and 18 deletions.
diff --git a/src/Angular.js b/src/Angular.js
@@ -58,7 +58,7 @@ var /** holds major version number for IE or NaN for real browsers */
     toString          = Object.prototype.toString,
 
 
-    _angular          = window.angular, 
+    _angular          = window.angular,
     /** @name angular */
     angular           = window.angular || (window.angular = {}),
     angularModule,
@@ -964,22 +964,38 @@ function angularInit(element, bootstrap) {
  * @returns {AUTO.$injector} Returns the newly created injector for this app.
  */
 function bootstrap(element, modules) {
-  element = jqLite(element);
-  modules = modules || [];
-  modules.unshift(['$provide', function($provide) {
-    $provide.value('$rootElement', element);
-  }]);
-  modules.unshift('ng');
-  var injector = createInjector(modules);
-  injector.invoke(
-    ['$rootScope', '$rootElement', '$compile', '$injector', function(scope, element, compile, injector){
-      scope.$apply(function() {
-        element.data('$injector', injector);
-        compile(element)(scope);
-      });
-    }]
-  );
-  return injector;
+  var resumeBootstrapInternal = function() {
+    element = jqLite(element);
+    modules = modules || [];
+    modules.unshift(['$provide', function($provide) {
+      $provide.value('$rootElement', element);
+    }]);
+    modules.unshift('ng');
+    var injector = createInjector(modules);
+    injector.invoke(['$rootScope', '$rootElement', '$compile', '$injector',
+       function(scope, element, compile, injector) {
+        scope.$apply(function() {
+          element.data('$injector', injector);
+          compile(element)(scope);
+        });
+      }]
+    );
+    return injector;
+  };
+
+  var NG_DEFER_BOOTSTRAP = /^NG_DEFER_BOOTSTRAP!/;
+
+  if (window && !NG_DEFER_BOOTSTRAP.test(window.name)) {
+    return resumeBootstrapInternal();
+  }
+
+  window.name = window.name.replace(NG_DEFER_BOOTSTRAP, '');
+  angular.resumeBootstrap = function(extraModules) {
+    forEach(extraModules, function(module) {
+      modules.push(module);
+    });
+    resumeBootstrapInternal();
+  };
 }
 
 var SNAKE_CASE_REGEXP = /[A-Z]/g;

diff --git a/test/AngularSpec.js b/test/AngularSpec.js
@@ -658,7 +658,7 @@ describe('angular', function() {
       var element = jqLite('<div>{{1+2}}</div>');
       var injector = angular.bootstrap(element);
       expect(injector).toBeDefined();
-      expect(element.data('$injector')).toBe(injector);
+      expect(element.injector()).toBe(injector);
       dealoc(element);
     });
 
@@ -672,6 +672,78 @@ describe('angular', function() {
       expect(element.html()).toBe('{{1+2}}');
       dealoc(element);
     });
+
+
+    describe('deferred bootstrap', function() {
+      var originalName = window.name,
+          element;
+
+      beforeEach(function() {
+        window.name = '';
+        element = jqLite('<div>{{1+2}}</div>');
+      });
+
+      afterEach(function() {
+        dealoc(element);
+        window.name = originalName;
+      });
+
+
+      it('should wait for extra modules', function() {
+        window.name = 'NG_DEFER_BOOTSTRAP!';
+        angular.bootstrap(element);
+
+        expect(element.html()).toBe('{{1+2}}');
+
+        angular.resumeBootstrap();
+
+        expect(element.html()).toBe('3');
+        expect(window.name).toEqual('');
+      });
+
+
+      it('should load extra modules', function() {
+        element = jqLite('<div>{{1+2}}</div>');
+        window.name = 'NG_DEFER_BOOTSTRAP!';
+
+        var bootstrapping = jasmine.createSpy('bootstrapping');
+        angular.bootstrap(element, [bootstrapping]);
+
+        expect(bootstrapping).not.toHaveBeenCalled();
+        expect(element.injector()).toBeUndefined();
+
+        angular.module('addedModule', []).value('foo', 'bar');
+        angular.resumeBootstrap(['addedModule']);
+
+        expect(bootstrapping).toHaveBeenCalledOnce();
+        expect(element.injector().get('foo')).toEqual('bar');
+      });
+
+
+      it('should not defer bootstrap without window.name cue', function() {
+        angular.bootstrap(element, []);
+        angular.module('addedModule', []).value('foo', 'bar');
+
+        expect(function() {
+          element.injector().get('foo');
+        }).toThrow('Unknown provider: fooProvider <- foo');
+
+        expect(element.injector().get('$http')).toBeDefined();
+      });
+
+
+      it('should restore the original window.name after bootstrap', function() {
+        window.name = 'NG_DEFER_BOOTSTRAP!my custom name';
+        angular.bootstrap(element);
+
+        expect(element.html()).toBe('{{1+2}}');
+
+        angular.resumeBootstrap();
+
+        expect(element.html()).toBe('3');
+        expect(window.name).toEqual('my custom name');
+      });
+    });
   });