fix(Compiler): add an error when a directive is null or undefined

fixes #1908

modules/angular2/src/core/compiler/compiler.js

@@ -92,7 +92,7 @@ export class Compiler {
   // Used for bootstrapping.
   compileInHost(componentTypeOrBinding:any):Promise<ProtoViewRef> {
     var componentBinding = this._bindDirective(componentTypeOrBinding);
-    this._assertTypeIsComponent(componentBinding);
+    Compiler._assertTypeIsComponent(componentBinding);
 
     var directiveMetadata = componentBinding.metadata;
     return this._render.compileHost(directiveMetadata).then( (hostRenderPv) => {
@@ -104,7 +104,7 @@ export class Compiler {
 
   compile(component: Type):Promise<ProtoViewRef> {
     var componentBinding = this._bindDirective(component);
-    this._assertTypeIsComponent(componentBinding);
+    Compiler._assertTypeIsComponent(componentBinding);
     var protoView = this._compile(componentBinding);
     var pvPromise = PromiseWrapper.isPromise(protoView) ? protoView : PromiseWrapper.resolve(protoView);
     return pvPromise.then( (appProtoView) => {
@@ -134,13 +134,21 @@ export class Compiler {
     if (isBlank(template)) {
       return null;
     }
-    var directives = ListWrapper.map(
-      this._flattenDirectives(template),
-      (directive) => this._bindDirective(directive)
-    );
-    var renderTemplate = this._buildRenderTemplate(component, template, directives);
+
+    var directives = this._flattenDirectives(template);
+
+    for (var i = 0; i < directives.length; i++) {
+      if (!Compiler._isValidDirective(directives[i])) {
+        throw new BaseException(
+            `Unexpected directive value '${stringify(directives[i])}' on the View of component '${stringify(component)}'`);
+      }
+    }
+
+    var boundDirectives = ListWrapper.map(directives,  (directive) => this._bindDirective(directive));
+
+    var renderTemplate = this._buildRenderTemplate(component, template, boundDirectives);
     pvPromise = this._render.compile(renderTemplate).then( (renderPv) => {
-      return this._compileNestedProtoViews(componentBinding, renderPv, directives);
+      return this._compileNestedProtoViews(componentBinding, renderPv, boundDirectives);
     });
 
     MapWrapper.set(this._compiling, component, pvPromise);
@@ -227,7 +235,7 @@ export class Compiler {
     return directives;
   }
 
-  _flattenList(tree:List<any>, out:List<Type>):void {
+  _flattenList(tree:List<any>, out:List<any> /*<Type|Binding>*/):void {
     for (var i = 0; i < tree.length; i++) {
       var item = tree[i];
       if (ListWrapper.isList(item)) {
@@ -238,7 +246,11 @@ export class Compiler {
     }
   }
 
-  _assertTypeIsComponent(directiveBinding:DirectiveBinding):void {
+  static _isValidDirective(value: any): boolean {
+    return isPresent(value) && (value instanceof Type || value instanceof Binding);
+  }
+
+  static _assertTypeIsComponent(directiveBinding:DirectiveBinding):void {
     if (directiveBinding.metadata.type !== renderApi.DirectiveMetadata.COMPONENT_TYPE) {
       throw new BaseException(`Could not load '${stringify(directiveBinding.key.token)}' because it is not a component.`);
     }

modules/angular2/test/core/compiler/integration_spec.js

@@ -9,6 +9,7 @@ import {
   expect,
   iit,
   inject,
+  IS_DARTIUM,
   beforeEachBindings,
   it,
   xit
@@ -823,6 +824,57 @@ export function main() {
     });
 
     describe("error handling", () => {
+      it('should report a meaningful error when a directive is missing annotation',
+        inject([TestBed, AsyncTestCompleter], (tb, async) => {
+
+        tb.overrideView(MyComp, new View({
+          directives: [SomeDirectiveMissingAnnotation]
+        }));
+
+        PromiseWrapper.catchError(
+            tb.createView(MyComp, {context: ctx}),
+            (e) => {
+              expect(e.message).toEqual('No Directive annotation found on SomeDirectiveMissingAnnotation');
+              async.done();
+            }
+        );
+      }));
+
+      it('should report a meaningful error when a directive is null',
+        inject([TestBed, AsyncTestCompleter], (tb, async) => {
+
+        tb.overrideView(MyComp, new View({
+          directives: [[null]]
+        }));
+
+        PromiseWrapper.catchError(
+            tb.createView(MyComp, {context: ctx}),
+            (e) => {
+              expect(e.message).toEqual("Unexpected directive value 'null' on the View of component 'MyComp'");
+              async.done();
+            }
+        );
+      }));
+
+      if (!IS_DARTIUM) {
+        it('should report a meaningful error when a directive is undefined',
+          inject([TestBed, AsyncTestCompleter], (tb, async) => {
+
+          var undefinedValue;
+
+          tb.overrideView(MyComp, new View({
+            directives: [undefinedValue]
+          }));
+
+          PromiseWrapper.catchError(
+              tb.createView(MyComp, {context: ctx}),
+              (e) => {
+                expect(e.message).toEqual("Unexpected directive value 'undefined' on the View of component 'MyComp'");
+                async.done();
+              }
+          );
+        }));
+      }
 
       it('should specify a location of an error that happened during change detection (text)',
         inject([TestBed, AsyncTestCompleter], (tb, async) => {
@@ -1110,7 +1162,6 @@ class MyComp {
   }
 }
 
-
 @Component({
   selector: 'component-with-pipes',
   properties: {
@@ -1159,6 +1210,8 @@ class ChildCompUsingService {
 })
 class SomeDirective { }
 
+class SomeDirectiveMissingAnnotation { }
+
 @Component({
   selector: 'cmp-with-parent'
 })

modules/angular2/test/reflection/reflector_spec.js

@@ -121,6 +121,11 @@ export function main() {
         reflector.registerType(TestObj, {"annotations" : [1,2]});
         expect(reflector.annotations(TestObj)).toEqual([1,2]);
       });
+
+      it("should work for a clas without annotations", () => {
+        var p = reflector.annotations(ClassWithoutAnnotations);
+        expect(p).toEqual([]);
+      });
     });
 
     describe("getter", () => {