angular · devversion · Jun 5, 2020 · Jun 5, 2020 · Jun 5, 2020 · Jun 9, 2020
diff --git a/packages/bazel/src/ngc-wrapped/index.ts b/packages/bazel/src/ngc-wrapped/index.ts
@@ -191,23 +191,8 @@ export function compile({
     fileLoader = new UncachedFileLoader();
   }
 
-  compilerOpts.annotationsAs = 'static fields';
-  if (!bazelOpts.es5Mode) {
-    if (bazelOpts.workspaceName === 'google3') {
-      compilerOpts.annotateForClosureCompiler = true;
-    } else {
-      compilerOpts.annotateForClosureCompiler = false;
-    }
-  }
-
   // Detect from compilerOpts whether the entrypoint is being invoked in Ivy mode.
   const isInIvyMode = !!compilerOpts.enableIvy;
-
-  // Disable downleveling and Closure annotation if in Ivy mode.
-  if (isInIvyMode) {
-    compilerOpts.annotationsAs = 'decorators';
-  }
-
   if (!compilerOpts.rootDirs) {
     throw new Error('rootDirs is not set!');
   }
@@ -264,9 +249,6 @@ export function compile({
   }
 
   if (isInIvyMode) {
-    // Also need to disable decorator downleveling in the BazelHost in Ivy mode.
-    bazelHost.transformDecorators = false;
-
     const delegate = bazelHost.shouldSkipTsickleProcessing.bind(bazelHost);
     bazelHost.shouldSkipTsickleProcessing = (fileName: string) => {
       // The base implementation of shouldSkipTsickleProcessing checks whether `fileName` is part of
@@ -277,12 +259,36 @@ export function compile({
     };
   }
 
+  // By default, disable tsickle decorator transforming in the tsickle compiler host.
+  // The Angular compilers have their own logic for decorator processing and we wouldn't
+  // want tsickle to interfere with that.
+  bazelHost.transformDecorators = false;
+
+  // By default in the `prodmode` output, we do not add annotations for closure compiler.
+  // Though, if we are building inside `google3`, closure annotations are desired for
+  // prodmode output, so we enable it by default. The defaults can be overridden by
+  // setting the `annotateForClosureCompiler` compiler option in the user tsconfig.
+  if (!bazelOpts.es5Mode) {
+    if (bazelOpts.workspaceName === 'google3') {
+      compilerOpts.annotateForClosureCompiler = true;
+      // Enable the tsickle decorator transform in google3 with Ivy mode enabled. The tsickle
+      // decorator transformation is still needed. This might be because of custom decorators
+      // with the `@Annotation` JSDoc that will be processed by the tsickle decorator transform.
+      // TODO: Figure out why this is needed in g3 and how we can improve this. FW-2225
+      if (isInIvyMode) {
+        bazelHost.transformDecorators = true;
+      }
+    } else {
+      compilerOpts.annotateForClosureCompiler = false;
+    }
+  }
+
+  // The `annotateForClosureCompiler` Angular compiler option is not respected by default
+  // as ngc-wrapped handles tsickle emit on its own. This means that we need to update
+  // the tsickle compiler host based on the `annotateForClosureCompiler` flag.
   if (compilerOpts.annotateForClosureCompiler) {
     bazelHost.transformTypesToClosure = true;
   }
-  if (compilerOpts.annotateForClosureCompiler || compilerOpts.annotationsAs === 'static fields') {
-    bazelHost.transformDecorators = true;
-  }
 
   const origBazelHostFileExist = bazelHost.fileExists;
   bazelHost.fileExists = (fileName: string) => {

diff --git a/packages/bazel/test/ng_package/example_package.golden b/packages/bazel/test/ng_package/example_package.golden
@@ -253,10 +253,10 @@ Hello
     var MySecondService = /** @class */ (function () {
         function MySecondService() {
         }
+        MySecondService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MySecondService_Factory() { return new MySecondService(); }, token: MySecondService, providedIn: "root" });
         MySecondService.decorators = [
             { type: i0.Injectable, args: [{ providedIn: 'root' },] }
         ];
-        MySecondService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MySecondService_Factory() { return new MySecondService(); }, token: MySecondService, providedIn: "root" });
         return MySecondService;
     }());
 
@@ -271,14 +271,13 @@ Hello
         function MyService(secondService) {
             this.secondService = secondService;
         }
+        MyService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MyService_Factory() { return new MyService(i0.ɵɵinject(MySecondService)); }, token: MyService, providedIn: "root" });
         MyService.decorators = [
             { type: i0.Injectable, args: [{ providedIn: 'root' },] }
         ];
-        /** @nocollapse */
         MyService.ctorParameters = function () { return [
             { type: MySecondService }
         ]; };
-        MyService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MyService_Factory() { return new MyService(i0.ɵɵinject(MySecondService)); }, token: MyService, providedIn: "root" });
         return MyService;
     }());
 
@@ -317,7 +316,7 @@ Hello
      *
      * Use of this source code is governed by an MIT-style license that can be
      * found in the LICENSE file at https://angular.io/license
-     */var n=function(){function e(){}return e.decorators=[{type:t.Injectable,args:[{providedIn:"root"}]}],e.ɵprov=t.ɵɵdefineInjectable({factory:function t(){return new e},token:e,providedIn:"root"}),e}(),r=function(){function e(e){this.secondService=e}return e.decorators=[{type:t.Injectable,args:[{providedIn:"root"}]}],e.ctorParameters=function(){return[{type:n}]},e.ɵprov=t.ɵɵdefineInjectable({factory:function r(){return new e(t.ɵɵinject(n))},token:e,providedIn:"root"}),e}();
+     */var n=function(){function e(){}return e.ɵprov=t.ɵɵdefineInjectable({factory:function t(){return new e},token:e,providedIn:"root"}),e.decorators=[{type:t.Injectable,args:[{providedIn:"root"}]}],e}(),r=function(){function e(e){this.secondService=e}return e.ɵprov=t.ɵɵdefineInjectable({factory:function r(){return new e(t.ɵɵinject(n))},token:e,providedIn:"root"}),e.decorators=[{type:t.Injectable,args:[{providedIn:"root"}]}],e.ctorParameters=function(){return[{type:n}]},e}();
 /**
      * @license
      * Copyright Google LLC All Rights Reserved.
@@ -602,18 +601,17 @@ let MyService = /** @class */ (() => {
             this.secondService = secondService;
         }
     }
+    MyService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MyService_Factory() { return new MyService(i0.ɵɵinject(i1.MySecondService)); }, token: MyService, providedIn: "root" });
     MyService.decorators = [
         { type: Injectable, args: [{ providedIn: 'root' },] }
     ];
-    /** @nocollapse */
     MyService.ctorParameters = () => [
         { type: MySecondService }
     ];
-    MyService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MyService_Factory() { return new MyService(i0.ɵɵinject(i1.MySecondService)); }, token: MyService, providedIn: "root" });
     return MyService;
 })();
 export { MyService };
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+//# sourceMappingURL=data:application/json;base64,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
 
 --- esm2015/imports/second.js ---
 
@@ -629,14 +627,14 @@ import * as i0 from "@angular/core";
 let MySecondService = /** @class */ (() => {
     class MySecondService {
     }
+    MySecondService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MySecondService_Factory() { return new MySecondService(); }, token: MySecondService, providedIn: "root" });
     MySecondService.decorators = [
         { type: Injectable, args: [{ providedIn: 'root' },] }
     ];
-    MySecondService.ɵprov = i0.ɵɵdefineInjectable({ factory: function MySecondService_Factory() { return new MySecondService(); }, token: MySecondService, providedIn: "root" });
     return MySecondService;
 })();
 export { MySecondService };
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 --- esm2015/index.js ---
 
@@ -800,7 +798,7 @@ export { A11yModule };
  * License: MIT
  */
 
-import { Injectable, ɵɵdefineInjectable, ɵɵinject } from '@angular/core';
+import { ɵɵdefineInjectable, Injectable, ɵɵinject } from '@angular/core';
 
 /**
  * @license
@@ -812,10 +810,10 @@ import { Injectable, ɵɵdefineInjectable, ɵɵinject } from '@angular/core';
 let MySecondService = /** @class */ (() => {
     class MySecondService {
     }
+    MySecondService.ɵprov = ɵɵdefineInjectable({ factory: function MySecondService_Factory() { return new MySecondService(); }, token: MySecondService, providedIn: "root" });
     MySecondService.decorators = [
         { type: Injectable, args: [{ providedIn: 'root' },] }
     ];
-    MySecondService.ɵprov = ɵɵdefineInjectable({ factory: function MySecondService_Factory() { return new MySecondService(); }, token: MySecondService, providedIn: "root" });
     return MySecondService;
 })();
 
@@ -832,14 +830,13 @@ let MyService = /** @class */ (() => {
             this.secondService = secondService;
         }
     }
+    MyService.ɵprov = ɵɵdefineInjectable({ factory: function MyService_Factory() { return new MyService(ɵɵinject(MySecondService)); }, token: MyService, providedIn: "root" });
     MyService.decorators = [
         { type: Injectable, args: [{ providedIn: 'root' },] }
     ];
-    /** @nocollapse */
     MyService.ctorParameters = () => [
         { type: MySecondService }
     ];
-    MyService.ɵprov = ɵɵdefineInjectable({ factory: function MyService_Factory() { return new MyService(ɵɵinject(MySecondService)); }, token: MyService, providedIn: "root" });
     return MyService;
 })();
 

diff --git a/packages/compiler-cli/BUILD.bazel b/packages/compiler-cli/BUILD.bazel
@@ -29,6 +29,7 @@ ts_library(
         "//packages/compiler-cli/src/ngtsc/file_system",
         "//packages/compiler-cli/src/ngtsc/indexer",
         "//packages/compiler-cli/src/ngtsc/perf",
+        "//packages/compiler-cli/src/ngtsc/reflection",
         "//packages/compiler-cli/src/ngtsc/typecheck",
         "@npm//@bazel/typescript",
         "@npm//@types/node",

diff --git a/packages/compiler-cli/src/main.ts b/packages/compiler-cli/src/main.ts
@@ -89,18 +89,9 @@ export function mainDiagnosticsForTest(
 }
 
 function createEmitCallback(options: api.CompilerOptions): api.TsEmitCallback|undefined {
-  const transformDecorators =
-      (options.enableIvy === false && options.annotationsAs !== 'decorators');
-  const transformTypesToClosure = options.annotateForClosureCompiler;
-  if (!transformDecorators && !transformTypesToClosure) {
+  if (!options.annotateForClosureCompiler) {
     return undefined;
   }
-  if (transformDecorators) {
-    // This is needed as a workaround for https://github.com/angular/tsickle/issues/635
-    // Otherwise tsickle might emit references to non imported values
-    // as TypeScript elided the import.
-    options.emitDecoratorMetadata = true;
-  }
   const tsickleHost: Pick<
       tsickle.TsickleHost,
       'shouldSkipTsickleProcessing'|'pathToModuleName'|'shouldIgnoreWarningsForPath'|
@@ -115,41 +106,29 @@ function createEmitCallback(options: api.CompilerOptions): api.TsEmitCallback|un
     googmodule: false,
     untyped: true,
     convertIndexImportShorthand: false,
-    transformDecorators,
-    transformTypesToClosure,
+    // Decorators are transformed as part of the Angular compiler programs. To avoid
+    // conflicts, we disable decorator transformations for tsickle.
+    transformDecorators: false,
+    transformTypesToClosure: true,
   };
 
-  if (options.annotateForClosureCompiler || options.annotationsAs === 'static fields') {
-    return ({
-             program,
-             targetSourceFile,
-             writeFile,
-             cancellationToken,
-             emitOnlyDtsFiles,
-             customTransformers = {},
-             host,
-             options
-           }) =>
-               // tslint:disable-next-line:no-require-imports only depend on tsickle if requested
-        require('tsickle').emitWithTsickle(
-            program, {...tsickleHost, options, host, moduleResolutionHost: host}, host, options,
-            targetSourceFile, writeFile, cancellationToken, emitOnlyDtsFiles, {
-              beforeTs: customTransformers.before,
-              afterTs: customTransformers.after,
-            });
-  } else {
-    return ({
-             program,
-             targetSourceFile,
-             writeFile,
-             cancellationToken,
-             emitOnlyDtsFiles,
-             customTransformers = {},
-           }) =>
-               program.emit(
-                   targetSourceFile, writeFile, cancellationToken, emitOnlyDtsFiles,
-                   {after: customTransformers.after, before: customTransformers.before});
-  }
+  return ({
+           program,
+           targetSourceFile,
+           writeFile,
+           cancellationToken,
+           emitOnlyDtsFiles,
+           customTransformers = {},
+           host,
+           options
+         }) =>
+             // tslint:disable-next-line:no-require-imports only depend on tsickle if requested
+      require('tsickle').emitWithTsickle(
+          program, {...tsickleHost, options, host, moduleResolutionHost: host}, host, options,
+          targetSourceFile, writeFile, cancellationToken, emitOnlyDtsFiles, {
+            beforeTs: customTransformers.before,
+            afterTs: customTransformers.after,
+          });
 }
 
 export interface NgcParsedConfiguration extends ParsedConfiguration {

diff --git a/packages/compiler-cli/src/ngtsc/core/src/compiler.ts b/packages/compiler-cli/src/ngtsc/core/src/compiler.ts
@@ -752,7 +752,7 @@ export class NgCompiler {
 /**
  * Determine if the given `Program` is @angular/core.
  */
-function isAngularCorePackage(program: ts.Program): boolean {
+export function isAngularCorePackage(program: ts.Program): boolean {
   // Look for its_just_angular.ts somewhere in the program.
   const r3Symbols = getR3SymbolsFile(program);
   if (r3Symbols === null) {

diff --git a/packages/compiler-cli/src/tooling.ts b/packages/compiler-cli/src/tooling.ts
@@ -13,7 +13,10 @@
  * Any changes to this file should be discussed with the Angular CLI team.
  */
 
+import * as ts from 'typescript';
 
+import {TypeScriptReflectionHost} from './ngtsc/reflection';
+import {getDownlevelDecoratorsTransform} from './transformers/downlevel_decorators_transform';
 
 /**
  * Known values for global variables in `@angular/core` that Terser should set using
@@ -28,3 +31,19 @@ export const GLOBAL_DEFS_FOR_TERSER_WITH_AOT = {
   ...GLOBAL_DEFS_FOR_TERSER,
   ngJitMode: false,
 };
+
+/**
+ * Transform for downleveling Angular decorators and Angular-decorated class constructor
+ * parameters for dependency injection. This transform can be used by the CLI for JIT-mode
+ * compilation where decorators should be preserved, but downleveled so that apps are not
+ * exposed to the ES2015 temporal dead zone limitation in TypeScript's metadata.
+ * See https://github.com/angular/angular-cli/pull/14473 for more details.
+ */
+export function decoratorDownlevelTransformerFactory(program: ts.Program):
+    ts.TransformerFactory<ts.SourceFile> {
+  const typeChecker = program.getTypeChecker();
+  const reflectionHost = new TypeScriptReflectionHost(typeChecker);
+  return getDownlevelDecoratorsTransform(
+      typeChecker, reflectionHost, [], /* isCore */ false,
+      /* enableClosureCompiler */ false);
+}