Ignore --fast-startup flag, assume true

Change-Id: I7a41160bf7f5bb403177b19613de2889e0fa2b44
Reviewed-on: https://dart-review.googlesource.com/c/87424
Reviewed-by: Sigmund Cherem <sigmund@google.com>

CHANGELOG.md

@@ -32,6 +32,13 @@
 
 #### dart2js
 
+* `--fast-startup` is forced on.  The flag is silently ignored and will be
+  deprecated and then removed at a later date.
+
+  The alternative 'full emitter' is no longer available. The generated code for
+  `--fast-startup` is optimized to load faster, even though it can be slightly
+  larger.
+
 * We fixed a bug in how deferred constructor calls were incorrectly not
   marked as deferred. The old behavior didn't cause breakages, but was imprecise
   and pushed more code to the main output unit.

pkg/compiler/lib/src/dart2js.dart

@@ -340,7 +340,7 @@ Future<api.CompilationResult> compile(List<String> argv,
     new OptionHandler('--out=.+|-o.*', setOutput, multipleArguments: true),
     new OptionHandler('-O.*', setOptimizationLevel),
     new OptionHandler(Flags.allowMockCompilation, ignoreOption),
-    new OptionHandler(Flags.fastStartup, passThrough),
+    new OptionHandler(Flags.fastStartup, ignoreOption),
     new OptionHandler(Flags.genericMethodSyntax, ignoreOption),
     new OptionHandler(Flags.initializingFormalAccess, ignoreOption),
     new OptionHandler(Flags.minify, passThrough),

pkg/compiler/lib/src/js_backend/backend.dart

@@ -387,12 +387,13 @@ class JavaScriptBackend {
 
   JavaScriptBackend(this.compiler,
       {bool generateSourceMap: true,
-      bool useStartupEmitter: false,
+      bool useStartupEmitter: true,
       bool useMultiSourceInfo: false,
       bool useNewSourceInfo: false})
       : this.sourceInformationStrategy =
             compiler.backendStrategy.sourceInformationStrategy,
         constantCompilerTask = new JavaScriptConstantTask(compiler) {
+    useStartupEmitter = true;
     CommonElements commonElements = compiler.frontendStrategy.commonElements;
     _backendUsageBuilder =
         new BackendUsageBuilderImpl(compiler.frontendStrategy);

pkg/compiler/lib/src/options.dart

@@ -244,9 +244,9 @@ class CompilerOptions implements DiagnosticOptions {
   /// (experimental)
   bool useNewSourceInfo = false;
 
-  /// Whether the user requested to use the fast startup emitter. The full
-  /// emitter might still be used if the program uses dart:mirrors.
-  bool useStartupEmitter = false;
+  /// Whether the user requested to use the fast startup emitter. Always `true`.
+  // TODO(sra): Remove.
+  bool useStartupEmitter = true;
 
   /// Enable verbose printing during compilation. Includes a time-breakdown
   /// between phases at the end.
@@ -358,7 +358,7 @@ class CompilerOptions implements DiagnosticOptions {
           !_hasOption(options, Flags.noFrequencyBasedMinification)
       ..useMultiSourceInfo = _hasOption(options, Flags.useMultiSourceInfo)
       ..useNewSourceInfo = _hasOption(options, Flags.useNewSourceInfo)
-      ..useStartupEmitter = _hasOption(options, Flags.fastStartup)
+      ..useStartupEmitter = true
       ..verbose = _hasOption(options, Flags.verbose)
       ..showInternalProgress = _hasOption(options, Flags.progress)
       ..readDataUri = _extractUriOption(options, '${Flags.readData}=')
@@ -390,6 +390,8 @@ class CompilerOptions implements DiagnosticOptions {
   }
 
   void deriveOptions() {
+    useStartupEmitter = true;
+
     if (benchmarkingProduction) {
       useStartupEmitter = true;
       trustPrimitives = true;

tests/compiler/dart2js/codegen/class_codegen_test.dart

@@ -66,14 +66,14 @@ main() {
 
 twoClasses() async {
   String generated = await compileAll(TEST_ONE);
-  Expect.isTrue(generated.contains(new RegExp('A: {[ \n]*"\\^": "Object;"')));
-  Expect.isTrue(generated.contains(new RegExp('B: {[ \n]*"\\^": "Object;"')));
+  Expect.isTrue(generated.contains('A: function A()'));
+  Expect.isTrue(generated.contains('B: function B()'));
 }
 
 subClass() async {
   checkOutput(String generated) {
-    Expect.isTrue(generated.contains(new RegExp('A: {[ \n]*"\\^": "Object;"')));
-    Expect.isTrue(generated.contains(new RegExp('B: {[ \n]*"\\^": "A;"')));
+    Expect.isTrue(generated.contains(RegExp(r'_inherit\(.\.A, .\.Object\)')));
+    Expect.isTrue(generated.contains(RegExp(r'_inherit\(.\.B, .\.A\)')));
   }
 
   checkOutput(await compileAll(TEST_TWO));
@@ -82,12 +82,15 @@ subClass() async {
 
 fieldTest() async {
   String generated = await compileAll(TEST_FOUR);
-  Expect.isTrue(generated
-      .contains(new RegExp('B: {[ \n]*"\\^": "A;y,z,x",[ \n]*static:')));
+  Expect.isTrue(generated.contains(RegExp(r'B: function B\(t0, t1, t2\) {'
+      r'\s*this.y = t0;'
+      r'\s*this.z = t1;'
+      r'\s*this.x = t2;')));
 }
 
 constructor1() async {
   String generated = await compileAll(TEST_FIVE);
+  print('--------------------\n$generated\n');
   Expect.isTrue(generated.contains(new RegExp(r"new [$A-Z]+\.A\(a\);")));
 }
 

tests/compiler/dart2js/codegen/gvn_test.dart

@@ -108,24 +108,22 @@ main() {
 main() {
   runTests() async {
     await compile(TEST_ONE, entry: 'foo', check: (String generated) {
-      RegExp regexp = new RegExp(r"1 \+ [a-z]+");
+      RegExp regexp = RegExp(r"1 \+ [a-z]+");
       checkNumberOfMatches(regexp.allMatches(generated).iterator, 1);
     });
     await compile(TEST_TWO, entry: 'foo', check: (String generated) {
-      checkNumberOfMatches(
-          new RegExp("length").allMatches(generated).iterator, 1);
+      checkNumberOfMatches(RegExp("length").allMatches(generated).iterator, 1);
     });
     await compile(TEST_THREE, entry: 'foo', check: (String generated) {
-      checkNumberOfMatches(
-          new RegExp("number").allMatches(generated).iterator, 1);
+      checkNumberOfMatches(RegExp("number").allMatches(generated).iterator, 1);
     });
     await compile(TEST_FOUR, entry: 'foo', check: (String generated) {
-      checkNumberOfMatches(new RegExp("shr").allMatches(generated).iterator, 1);
+      checkNumberOfMatches(RegExp("shr").allMatches(generated).iterator, 1);
     });
 
     await compileAll(TEST_FIVE).then((generated) {
       checkNumberOfMatches(
-          new RegExp("get\\\$foo").allMatches(generated).iterator, 1);
+          RegExp(r"get\$foo\(").allMatches(generated).iterator, 1);
     });
     await compileAll(TEST_SIX).then((generated) {
       Expect.isTrue(generated.contains('for (t1 = a.field === 54; t1;)'));

tests/compiler/dart2js/codegen/no_constructor_body_test.dart

@@ -20,9 +20,8 @@ main() {
 main() {
   runTest() async {
     String generated = await compileAll(TEST);
-
-    Expect.isTrue(generated
-        .contains(new RegExp('A: {[ \n]*"\\^": "Object;",[ \n]*static:')));
+    // No methods (including no constructor body method.
+    Expect.isTrue(generated.contains('.A.prototype = {}'));
   }
 
   asyncTest(() async {

tests/compiler/dart2js/codegen/no_duplicate_constructor_body_test.dart

@@ -18,9 +18,14 @@ main() {
 main() {
   runTest() async {
     String generated = await compileAll(CODE);
-    RegExp regexp = new RegExp(r'\A: {[ \n]*"\^": "[A-Za-z]+;"');
+
+    RegExp regexp = RegExp(r'\.A\.prototype = {');
     Iterator<Match> matches = regexp.allMatches(generated).iterator;
     checkNumberOfMatches(matches, 1);
+
+    RegExp regexp2 = RegExp(r'A\$\w+: function');
+    Iterator<Match> matches2 = regexp2.allMatches(generated).iterator;
+    checkNumberOfMatches(matches2, 1);
   }
 
   asyncTest(() async {

tests/compiler/dart2js/deferred/inline_restrictions_test.dart

@@ -57,7 +57,8 @@ void main() {
 
     // Test that inlineSameContext was inlined into lib1.
     RegExp re4 = new RegExp(r"inline same context");
-    Expect.isFalse(re4.hasMatch(lib3Output));
+    // Output can be null when it contains no code.
+    Expect.isTrue(lib3Output == null || !re4.hasMatch(lib3Output));
     Expect.isTrue(re4.hasMatch(lib1Output));
   });
 }

tests/compiler/dart2js/end_to_end/uri_retention_test.dart

@@ -1,64 +0,0 @@
-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-library dart2js.test.uri_retention_test;
-
-import 'dart:async';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:compiler/compiler_new.dart';
-import 'package:compiler/src/commandline_options.dart';
-import 'package:expect/expect.dart';
-import '../helpers/memory_compiler.dart' show runCompiler, OutputCollector;
-
-Future<String> compileSources(sources, {bool minify}) async {
-  var options = <String>[];
-  if (minify) options.add(Flags.minify);
-  OutputCollector outputCollector = new OutputCollector();
-  await runCompiler(
-      memorySourceFiles: sources,
-      options: options,
-      outputProvider: outputCollector);
-  return outputCollector.getOutput('', OutputType.js);
-}
-
-Future test(sources, {bool libName, bool fileName}) {
-  return compileSources(sources, minify: false).then((output) {
-    // Unminified the sources should always contain the library name and the
-    // file name.
-    Expect.isTrue(output.contains("main_lib"));
-    Expect.isTrue(output.contains("main.dart"));
-  }).then((_) {
-    compileSources(sources, minify: true).then((output) {
-      Expect.equals(libName, output.contains("main_lib"));
-      Expect.isFalse(output.contains("main.dart"));
-    });
-  });
-}
-
-void main() {
-  runTests() async {
-    await test(MEMORY_SOURCE_FILES1, libName: false, fileName: false);
-  }
-
-  asyncTest(() async {
-    print('--test from kernel------------------------------------------------');
-    await runTests();
-  });
-}
-
-const MEMORY_SOURCE_FILES1 = const <String, String>{
-  'main.dart': """
-library main_lib;
-
-class A {
-  final uri = "foo";
-}
-
-main() {
-  print(Uri.base);
-  print(new A().uri);
-}
-""",
-};

tests/compiler/dart2js/rti/emission/closure_function_type.dart

@@ -8,7 +8,7 @@ import 'package:meta/dart2js.dart';
 test(o) => o is Function();
 
 main() {
-  test(/*checks=[],functionType,instance*/ () {});
+  test(/*checks=[$signature],instance*/ () {});
   test(
 
       /*strong.checks=[],instance*/

tests/compiler/dart2js/rti/emission/closure_signature.dart

@@ -13,7 +13,7 @@ class A<T> {
 
   @NoInline()
   f() {
-    return /*checks=[],functionType,instance*/ (int t) {};
+    return /*checks=[$signature],instance*/ (int t) {};
   }
 }
 

tests/compiler/dart2js/rti/emission/runtime_type_instantiate_to_string1.dart

@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 main() {
-  /*strong.checks=[],functionType,instance*/
+  /*strong.checks=[$signature],instance*/
   /*omit.checks=[],instance*/
   T id<T>(T t) => t;
   int Function(int) x = id;

tests/compiler/dart2js/rti/emission/subtype_named_args.dart

@@ -53,50 +53,50 @@ typedef okWithDynamicFunc_2({int x, bool y, List<Map> z, classesFunc v});
 
 main() {
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({D a, B b, C c, A d}) {} is classesFunc);
   Expect.isTrue(
-      /*checks=[],functionType,instance*/
+      /*checks=[$signature],instance*/
       ({A a, A b, A c, A d}) {} is classesFunc);
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({D a, A1 b, A1 c, A1 d}) {} is classesFunc);
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({D a, A2 b, A2 c, A2 d}) {} is classesFunc);
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({D a, D b, D c, D d}) {} is classesFunc);
   Expect.isTrue(
-      /*checks=[],functionType,instance*/
+      /*checks=[$signature],instance*/
       ({var a, var b, var c, var d}) {} is classesFunc);
-  Expect.isTrue(/*checks=[],functionType,instance*/
+  Expect.isTrue(/*checks=[$signature],instance*/
       ({Object a, Object b, Object c, Object d}) {} is classesFunc);
 
-  Expect.isTrue(/*checks=[],functionType,instance*/
+  Expect.isTrue(/*checks=[$signature],instance*/
       ({Map<num, num> m, List<List<A1>> l, G<A, A1, A1, A1> g}) {}
           is genericsFunc);
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({Map<int, int> m, List<List<D>> l, G<D, D, D, D> g}) {} is genericsFunc);
   Expect.isTrue(
-      /*checks=[],functionType,instance*/
+      /*checks=[$signature],instance*/
       ({var m, var l, var g}) {} is genericsFunc);
   Expect.isTrue(
-      /*checks=[],functionType,instance*/
+      /*checks=[$signature],instance*/
       ({Object m, Object l, Object g}) {} is genericsFunc);
 
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({A x, G y, mixFunc z, var v}) {} is dynamicFunc);
   Expect.isTrue(
-      /*strong.checks=[],functionType,instance*/
+      /*strong.checks=[$signature],instance*/
       /*omit.checks=[],instance*/
       ({int x, bool y, List<Map> z, classesFunc v}) {} is dynamicFunc);
 
@@ -106,7 +106,7 @@ main() {
           {okWithClassesFunc_1 f1,
           okWithGenericsFunc_1 f2,
           okWithDynamicFunc_1 f3}) {} is funcFunc);
-  Expect.isTrue(/*checks=[],functionType,instance*/
+  Expect.isTrue(/*checks=[$signature],instance*/
       (
           {okWithClassesFunc_2 f1,
           okWithGenericsFunc_2 f2,