Decouple WorkItem from Compiler

pkg/compiler/lib/src/common/resolution.dart

 // Copyright (c) 2012, 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.common.resolution;
 
 import '../common.dart';
 import '../compile_time_constants.dart';
 import '../compiler.dart' show Compiler;
 import '../constants/expressions.dart' show ConstantExpression;
@@ skipping 23 matching lines @@
 import '../patch_parser.dart';
 import '../resolution/resolution.dart';
 import '../tree/tree.dart' show Send, TypeAnnotation;
 import '../universe/call_structure.dart' show CallStructure;
 import '../universe/world_impact.dart' show WorldImpact;
 import '../universe/feature.dart';
 import 'backend_api.dart';
 import 'work.dart' show WorkItem;
 
 /// [WorkItem] used exclusively by the [ResolutionEnqueuer].
-class ResolutionWorkItem extends WorkItem {
+abstract class ResolutionWorkItem implements WorkItem {
+  factory ResolutionWorkItem(Resolution resolution, AstElement element) =
+      _ResolutionWorkItem;
+}
+
+class _ResolutionWorkItem extends WorkItem implements ResolutionWorkItem {
   bool _isAnalyzed = false;
+  final Resolution resolution;
 
-  ResolutionWorkItem(AstElement element) : super(element);
+  _ResolutionWorkItem(this.resolution, AstElement element) : super(element);
 
-  WorldImpact run(Compiler compiler, ResolutionEnqueuer world) {
-    WorldImpact impact = compiler.analyze(this, world);
+  WorldImpact run() {
+    assert(invariant(element, !_isAnalyzed,
+        message: 'Element ${element} has already been analyzed'));
+    WorldImpact impact = resolution.computeWorldImpact(element);
     _isAnalyzed = true;
     return impact;
   }
-
-  bool get isAnalyzed => _isAnalyzed;
 }
 
 class ResolutionImpact extends WorldImpact {
   const ResolutionImpact();
 
   Iterable<Feature> get features => const <Feature>[];
   Iterable<MapLiteralUse> get mapLiterals => const <MapLiteralUse>[];
   Iterable<ListLiteralUse> get listLiterals => const <ListLiteralUse>[];
   Iterable<String> get constSymbolNames => const <String>[];
   Iterable<ConstantExpression> get constantLiterals =>
@@ skipping 137 matching lines @@
 
   void forgetElement(Element element);
 
   /// Returns `true` if [value] is the top-level [proxy] annotation from the
   /// core library.
   bool isProxyConstant(ConstantValue value);
 }
 
 /// A container of commonly used dependencies for tasks that involve parsing.
 abstract class ParsingContext {
-  factory ParsingContext(
-      DiagnosticReporter reporter,
-      ParserTask parser,
-      PatchParserTask patchParser,
-      Backend backend) = _ParsingContext;
+  factory ParsingContext(DiagnosticReporter reporter, ParserTask parser,
+      PatchParserTask patchParser, Backend backend) = _ParsingContext;
 
   DiagnosticReporter get reporter;
   ParserTask get parser;
   PatchParserTask get patchParser;
 
   /// Use [patchParser] directly instead.
   @deprecated
   void parsePatchClass(ClassElement cls);
 
   /// Use [parser] and measure directly instead.
   @deprecated
   measure(f());
 
   /// Get the [ScannerOptions] to scan the given [element].
   ScannerOptions getScannerOptionsFor(Element element);
 }
 
 class _ParsingContext implements ParsingContext {
   final DiagnosticReporter reporter;
   final ParserTask parser;
   final PatchParserTask patchParser;
   final Backend backend;
 
-  _ParsingContext(this.reporter, this.parser,
-      this.patchParser, this.backend);
+  _ParsingContext(this.reporter, this.parser, this.patchParser, this.backend);
 
   @override
   measure(f()) => parser.measure(f);
 
   @override
   void parsePatchClass(ClassElement cls) {
     patchParser.measure(() {
       if (cls.isPatch) {
         patchParser.parsePatchClassNode(cls);
       }
     });
   }
 
   @override
   ScannerOptions getScannerOptionsFor(Element element) => new ScannerOptions(
       canUseNative: backend.canLibraryUseNative(element.library));
 }