refactor(compiler): change ngc error handling

Do not print stack trace for user errors
Print stack trace for compiler internal errors

modules/@angular/compiler-cli/src/main.ts

@@ -22,14 +22,24 @@ function codegen(
   return CodeGenerator.create(ngOptions, cliOptions, program, host).codegen();
 }
 
+export function main(args: any, consoleError: any): Promise<number> {
+  const project = args.p || args.project || '.';
+  const cliOptions = new tsc.NgcCliOptions(args);
+
+  return tsc.main(project, cliOptions, codegen).then(() => 0).catch(e => {
+    if (e instanceof tsc.UserError) {
+      consoleError(e.message);
+      return Promise.resolve(0);
+    } else {
+      consoleError(e.stack);
+      consoleError('Compilation failed');
+      return Promise.resolve(1);
+    }
+  });
+}
+
 // CLI entry point
 if (require.main === module) {
   const args = require('minimist')(process.argv.slice(2));
-  const project = args.p || args.project || '.';
-  const cliOptions = new tsc.NgcCliOptions(args);
-  tsc.main(project, cliOptions, codegen).then(exitCode => process.exit(exitCode)).catch(e => {
-    console.error(e.stack);
-    console.error('Compilation failed');
-    process.exit(1);
-  });
-}
+  main(args, console.error).then((exitCode: number) => process.exit(exitCode));
+}

modules/@angular/compiler-cli/test/main_spec.ts

@@ -0,0 +1,108 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * 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
+ */
+
+import {makeTempDir} from '@angular/tsc-wrapped/test/test_support';
+import * as fs from 'fs';
+import * as path from 'path';
+
+import {main} from '../src/main';
+import {ReflectionCapabilities, reflector} from './private_import_core';
+
+
+describe('compiler-cli', () => {
+  let basePath: string;
+  let write: (fileName: string, content: string) => void;
+
+  beforeEach(() => {
+    basePath = makeTempDir();
+    write = (fileName: string, content: string) => {
+      fs.writeFileSync(path.join(basePath, fileName), content, {encoding: 'utf-8'});
+    };
+    write('tsconfig.json', `{
+      "compilerOptions": {
+        "experimentalDecorators": true,
+        "types": [],
+        "outDir": "built",
+        "declaration": true,
+        "module": "es2015"
+      },
+      "angularCompilerOptions": {
+        "annotateForClosureCompiler": true
+      },
+      "files": ["test.ts"]
+    }`);
+  });
+
+  // Restore reflector since AoT compiler will update it with a new static reflector
+  afterEach(() => { reflector.updateCapabilities(new ReflectionCapabilities()); });
+
+  it('should compile without errors', (done) => {
+    write('test.ts', 'export const A = 1;');
+
+    const mockConsole = {error: {}};
+
+    spyOn(mockConsole, 'error');
+
+    main({p: basePath}, mockConsole.error)
+        .then((exitCode) => {
+          expect(mockConsole.error).not.toHaveBeenCalled();
+          expect(exitCode).toEqual(0);
+          done();
+        })
+        .catch(e => done.fail(e));
+  });
+
+  it('should not print the stack trace if user input file does not exist', (done) => {
+    const mockConsole = {error: {}};
+
+    spyOn(mockConsole, 'error');
+
+    main({p: basePath}, mockConsole.error)
+        .then((exitCode) => {
+          expect(mockConsole.error).toHaveBeenCalled();
+          expect(mockConsole.error).not.toHaveBeenCalledWith('Compilation failed');
+          expect(exitCode).toEqual(0);
+          done();
+        })
+        .catch(e => done.fail(e));
+  });
+
+  it('should not print the stack trace if user input file is malformed', (done) => {
+    write('test.ts', 'foo bar');
+
+    const mockConsole = {error: {}};
+
+    spyOn(mockConsole, 'error');
+
+    main({p: basePath}, mockConsole.error)
+        .then((exitCode) => {
+          expect(mockConsole.error).toHaveBeenCalled();
+          expect(mockConsole.error).not.toHaveBeenCalledWith('Compilation failed');
+          expect(exitCode).toEqual(0);
+          done();
+        })
+        .catch(e => done.fail(e));
+  });
+
+  it('should print the stack trace on compiler internal errors', (done) => {
+    write('test.ts', 'export const A = 1;');
+
+    const mockConsole = {error: {}};
+
+    spyOn(mockConsole, 'error');
+
+    main({p: 'not-exist'}, mockConsole.error)
+        .then((exitCode) => {
+          expect(mockConsole.error).toHaveBeenCalled();
+          expect(mockConsole.error).toHaveBeenCalledWith('Compilation failed');
+          expect(exitCode).toEqual(1);
+          done();
+        })
+        .catch(e => done.fail(e));
+  });
+});

modules/@angular/compiler-cli/test/private_import_core.ts

@@ -0,0 +1,13 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * 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
+ */
+
+import {__core_private__ as r} from '@angular/core';
+
+export type ReflectionCapabilities = typeof r._ReflectionCapabilities;
+export var ReflectionCapabilities: typeof r.ReflectionCapabilities = r.ReflectionCapabilities;
+export var reflector: typeof r.reflector = r.reflector;

tools/@angular/tsc-wrapped/index.ts

@@ -7,7 +7,7 @@
  */
 
 export {DecoratorDownlevelCompilerHost, MetadataWriterHost} from './src/compiler_host';
-export {CodegenExtension, main} from './src/main';
+export {CodegenExtension, UserError, main} from './src/main';
 
 export {default as AngularCompilerOptions} from './src/options';
 export * from './src/cli_options';

tools/@angular/tsc-wrapped/src/main.ts

@@ -16,6 +16,8 @@ import NgOptions from './options';
 import {MetadataWriterHost, DecoratorDownlevelCompilerHost, TsickleCompilerHost} from './compiler_host';
 import {CliOptions} from './cli_options';
 
+export {UserError} from './tsc';
+
 export type CodegenExtension =
     (ngOptions: NgOptions, cliOptions: CliOptions, program: ts.Program, host: ts.CompilerHost) =>
         Promise<void>;

tools/@angular/tsc-wrapped/src/tsc.ts

@@ -24,6 +24,15 @@ export interface CompilerInterface {
   emit(program: ts.Program): number;
 }
 
+export class UserError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.message = message;
+    this.name = 'UserError';
+    this.stack = new Error().stack;
+  }
+}
+
 const DEBUG = false;
 
 function debug(msg: string, ...o: any[]) {
@@ -48,7 +57,7 @@ export function formatDiagnostics(diags: ts.Diagnostic[]): string {
 
 export function check(diags: ts.Diagnostic[]) {
   if (diags && diags.length && diags[0]) {
-    throw new Error(formatDiagnostics(diags));
+    throw new UserError(formatDiagnostics(diags));
   }
 }