perf(Compiler): do not resolve bindings for cached ProtoViews

Author: Jason Teplitz

modules/angular2/src/core/compiler/compiler.ts

@@ -2,6 +2,7 @@ import {Binding, resolveForwardRef, Injectable} from 'angular2/di';
 import {
   Type,
   isBlank,
+  isType,
   isPresent,
   BaseException,
   normalizeBlank,
@@ -103,16 +104,18 @@ export class Compiler {
   // Create a hostView as if the compiler encountered <hostcmp></hostcmp>.
   // Used for bootstrapping.
   compileInHost(componentTypeOrBinding: Type | Binding): Promise<ProtoViewRef> {
-    var componentBinding = this._bindDirective(componentTypeOrBinding);
-    Compiler._assertTypeIsComponent(componentBinding);
+    var componentType = isType(componentTypeOrBinding) ? componentTypeOrBinding :
+                                                         (<Binding>componentTypeOrBinding).token;
 
-    var directiveMetadata = componentBinding.metadata;
+    var hostAppProtoView = this._compilerCache.getHost(componentType);
     var hostPvPromise;
-    var component = <Type>componentBinding.key.token;
-    var hostAppProtoView = this._compilerCache.getHost(component);
     if (isPresent(hostAppProtoView)) {
       hostPvPromise = PromiseWrapper.resolve(hostAppProtoView);
     } else {
+      var componentBinding = this._bindDirective(componentTypeOrBinding);
+      Compiler._assertTypeIsComponent(componentBinding);
+
+      var directiveMetadata = componentBinding.metadata;
       hostPvPromise = this._render.compileHost(directiveMetadata)
                           .then((hostRenderPv) => {
                             return this._compileNestedProtoViews(componentBinding, hostRenderPv,

modules/angular2/test/core/compiler/compiler_spec.ts

@@ -373,6 +373,26 @@ export function main() {
              });
        }));
 
+    it('should not bind directives for cached components', inject([AsyncTestCompleter], (async) => {
+         // set up the cache with the test proto view
+         var mainPv: AppProtoView = createProtoView();
+         var cache: CompilerCache = new CompilerCache();
+         cache.setHost(MainComponent, mainPv);
+
+         // create the spy resolver
+         var reader: any = new SpyDirectiveResolver();
+
+         // create the compiler
+         var compiler = new Compiler(reader, cache, tplResolver, cmpUrlMapper, new UrlResolver(),
+                                     renderCompiler, protoViewFactory, new FakeAppRootUrl());
+         compiler.compileInHost(MainComponent)
+             .then((protoViewRef) => {
+               // the test should have failed if the resolver was called, so we're good
+               async.done();
+             });
+       }));
+
+
     it('should cache compiled nested components', inject([AsyncTestCompleter], (async) => {
          tplResolver.setView(MainComponent, new viewAnn.View({template: '<div></div>'}));
          tplResolver.setView(MainComponent2, new viewAnn.View({template: '<div></div>'}));
@@ -563,6 +583,13 @@ class SpyRenderCompiler extends SpyObject {
   noSuchMethod(m) { return super.noSuchMethod(m) }
 }
 
+@proxy
+@IMPLEMENTS(DirectiveResolver)
+class SpyDirectiveResolver extends SpyObject {
+  constructor() { super(DirectiveResolver); }
+  noSuchMethod(m) { return super.noSuchMethod(m) }
+}
+
 class FakeAppRootUrl extends AppRootUrl {
   get value() { return 'http://www.app.com'; }
 }