fix experiment support in ddc (#3178)

Previously we only passed experiments to Kernel, which was enough for null-safety to work but not for constructor-tearoffs.

I also marked the old `experiments` option as deprecated so you will get a warning if using it.

Author: jakemac53

build_web_compilers/CHANGELOG.md

@@ -1,5 +1,8 @@
-## 3.2.1-dev
+## 3.2.1
 
+- Fix enable-experiment flag support for dartdevc to also pass experiment flags
+  to dartdevc as well as kernel.
+- Add deprecation warning for the old `experiments` config.
 - Update `pub run` references to `dart run`.
 - Fix `doctor` command warnings for this package.
 

build_web_compilers/lib/builders.dart

@@ -27,7 +27,8 @@ Builder ddcBuilderUnsound(BuilderOptions options) =>
     ddcBuilder(options, soundNullSafety: false);
 
 Builder ddcBuilder(BuilderOptions options, {bool soundNullSafety = false}) {
-  validateOptions(options.config, _supportedOptions, 'build_web_compilers:ddc');
+  validateOptions(options.config, _supportedOptions, 'build_web_compilers:ddc',
+      deprecatedOptions: _deprecatedOptions);
   _ensureSameDdcOptions(options);
 
   return DevCompilerBuilder(
@@ -50,7 +51,8 @@ Builder ddcKernelBuilderSound(BuilderOptions options) =>
 
 Builder ddcKernelBuilder(BuilderOptions options,
     {bool soundNullSafety = false}) {
-  validateOptions(options.config, _supportedOptions, 'build_web_compilers:ddc');
+  validateOptions(options.config, _supportedOptions, 'build_web_compilers:ddc',
+      deprecatedOptions: _deprecatedOptions);
   _ensureSameDdcOptions(options);
 
   return KernelBuilder(
@@ -135,9 +137,11 @@ const _emitDebugSymbolsOption = 'emit-debug-symbols';
 const _trackUnusedInputsCompilerOption = 'track-unused-inputs';
 const _environmentOption = 'environment';
 const _experimentOption = 'experiments';
+const _deprecatedOptions = [
+  _experimentOption,
+];
 const _supportedOptions = [
   _environmentOption,
-  _experimentOption,
   _useIncrementalCompilerOption,
   _generateFullDillOption,
   _emitDebugSymbolsOption,

build_web_compilers/lib/src/dev_compiler_builder.dart

@@ -8,6 +8,7 @@ import 'dart:io';
 
 import 'package:bazel_worker/bazel_worker.dart';
 import 'package:build/build.dart';
+import 'package:build/experiments.dart';
 import 'package:build_modules/build_modules.dart';
 import 'package:path/path.dart' as p;
 import 'package:scratch_space/scratch_space.dart';
@@ -76,9 +77,6 @@ class DevCompilerBuilder implements Builder {
   /// Environment defines to pass to ddc (as -D variables).
   final Map<String, String> environment;
 
-  /// Experiments to pass to ddc (as --enable-experiment=<experiment> args).
-  final Iterable<String> experiments;
-
   /// Whether or not strong null safety should be enabled.
   final bool soundNullSafety;
 
@@ -92,7 +90,6 @@ class DevCompilerBuilder implements Builder {
       String? librariesPath,
       String? platformSdk,
       this.environment = const {},
-      this.experiments = const [],
       this.soundNullSafety = false})
       : platformSdk = platformSdk ?? sdkDir,
         librariesPath = librariesPath ??
@@ -144,7 +141,6 @@ class DevCompilerBuilder implements Builder {
           sdkKernelPath,
           librariesPath,
           environment,
-          experiments,
           soundNullSafety);
     } on DartDevcCompilationException catch (e) {
       await handleError(e);
@@ -166,7 +162,6 @@ Future<void> _createDevCompilerModule(
     String sdkKernelPath,
     String librariesPath,
     Map<String, String> environment,
-    Iterable<String> experiments,
     bool soundNullSafety,
     {bool debugMode = true}) async {
   var transitiveDeps = await buildStep.trackStage('CollectTransitiveDeps',
@@ -228,7 +223,8 @@ Future<void> _createDevCompilerModule(
         '--used-inputs-file=${usedInputsFile.uri.toFilePath()}',
       for (var source in module.sources) _sourceArg(source),
       for (var define in environment.entries) '-D${define.key}=${define.value}',
-      for (var experiment in experiments) '--enable-experiment=$experiment',
+      for (var experiment in enabledExperiments)
+        '--enable-experiment=$experiment',
       '--${soundNullSafety ? '' : 'no-'}sound-null-safety',
     ])
     ..inputs.add(Input()

build_web_compilers/pubspec.yaml

@@ -1,5 +1,5 @@
 name: build_web_compilers
-version: 3.2.1-dev
+version: 3.2.1
 description: Builder implementations wrapping Dart compilers.
 repository: https://github.com/dart-lang/build/tree/master/build_web_compilers