Create separate scopes for constructors, setters, and other members.

pkg/front_end/lib/src/fasta/builder/class_builder.dart

Index: pkg/front_end/lib/src/fasta/builder/class_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/builder/class_builder.dart b/pkg/front_end/lib/src/fasta/builder/class_builder.dart
index a6e892aeda295e0a3b0b72f2edbb8d0a9710b164..6cbecb53381ccacb3a42be09234794c967ab64c5 100644
--- a/pkg/front_end/lib/src/fasta/builder/class_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/class_builder.dart
@@ -15,12 +15,12 @@ import 'builder.dart'
         MetadataBuilder,
         MixinApplicationBuilder,
         NamedTypeBuilder,
+        Scope,
+        ScopeBuilder,
         TypeBuilder,
         TypeDeclarationBuilder,
         TypeVariableBuilder;
 
-import '../scope.dart' show AccessErrorBuilder, AmbiguousBuilder, Scope;
-
 abstract class ClassBuilder<T extends TypeBuilder, R>
     extends TypeDeclarationBuilder<T, R> {
   final List<TypeVariableBuilder> typeVariables;
@@ -29,7 +29,13 @@ abstract class ClassBuilder<T extends TypeBuilder, R>
 
   List<T> interfaces;
 
-  final Map<String, Builder> members;
+  final Scope scope;
+
+  final Scope constructors;
+
+  final ScopeBuilder scopeBuilder;
+
+  final ScopeBuilder constructorScopeBuilder;
 
   ClassBuilder(
       List<MetadataBuilder> metadata,
@@ -38,10 +44,13 @@ abstract class ClassBuilder<T extends TypeBuilder, R>
       this.typeVariables,
       this.supertype,
       this.interfaces,
-      this.members,
+      this.scope,
+      this.constructors,
       LibraryBuilder parent,
       int charOffset)
-      : super(metadata, modifiers, name, parent, charOffset);
+      : scopeBuilder = new ScopeBuilder(scope),
+        constructorScopeBuilder = new ScopeBuilder(constructors),
+        super(metadata, modifiers, name, parent, charOffset);
 
   /// Returns true if this class is the result of applying a mixin to its
   /// superclass.
@@ -51,10 +60,6 @@ abstract class ClassBuilder<T extends TypeBuilder, R>
 
   List<ConstructorReferenceBuilder> get constructorReferences => null;
 
-  Map<String, Builder> get constructors;
-
-  Map<String, Builder> get membersInScope => members;
-
   LibraryBuilder get library {
     LibraryBuilder library = parent;
     return library.partOfLibrary ?? library;
@@ -63,70 +68,23 @@ abstract class ClassBuilder<T extends TypeBuilder, R>
   @override
   int resolveConstructors(LibraryBuilder library) {
     if (constructorReferences == null) return 0;
-    Scope scope = computeInstanceScope(library.scope);
     for (ConstructorReferenceBuilder ref in constructorReferences) {
       ref.resolveIn(scope);
     }
     return constructorReferences.length;
   }
 
-  Scope computeInstanceScope(Scope parent) {
-    if (typeVariables != null) {
-      Map<String, Builder> local = <String, Builder>{};
-      for (TypeVariableBuilder t in typeVariables) {
-        local[t.name] = t;
-      }
-      parent = new Scope(local, null, parent, isModifiable: false);
-    }
-    return new Scope(membersInScope, null, parent, isModifiable: false);
-  }
-
   /// Used to lookup a static member of this class.
   Builder findStaticBuilder(String name, int charOffset, Uri fileUri,
       {bool isSetter: false}) {
-    Builder builder = members[name];
-    if (builder?.next != null) {
-      Builder getterBuilder;
-      Builder setterBuilder;
-      Builder current = builder;
-      while (current != null) {
-        if (current.isGetter && getterBuilder == null) {
-          getterBuilder = current;
-        } else if (current.isSetter && setterBuilder == null) {
-          setterBuilder = current;
-        } else {
-          return new AmbiguousBuilder(name, builder, charOffset, fileUri);
-        }
-        current = current.next;
-      }
-      if (getterBuilder?.isInstanceMember ?? false) {
-        getterBuilder = null;
-      }
-      if (setterBuilder?.isInstanceMember ?? false) {
-        setterBuilder = null;
-      }
-      builder = isSetter ? setterBuilder : getterBuilder;
-      if (builder == null) {
-        if (isSetter && getterBuilder != null) {
-          return new AccessErrorBuilder(
-              name, getterBuilder, charOffset, fileUri);
-        } else if (!isSetter && setterBuilder != null) {
-          return new AccessErrorBuilder(
-              name, setterBuilder, charOffset, fileUri);
-        }
-      }
-    }
-    if (builder == null) {
-      return null;
-    } else if (isSetter && builder.isGetter) {
-      return null;
-    } else {
-      return builder.isInstanceMember ? null : builder;
-    }
+    Builder builder = isSetter
+        ? scope.lookupSetter(name, charOffset, fileUri, isInstanceScope: false)
+        : scope.lookup(name, charOffset, fileUri, isInstanceScope: false);
+    return builder;
   }
 
   Builder findConstructorOrFactory(String name, int charOffset, Uri uri) {
-    return constructors[name];
+    return constructors.lookup(name, charOffset, uri);
   }
 
   /// Returns a map which maps the type variables of [superclass] to their
@@ -193,14 +151,14 @@ abstract class ClassBuilder<T extends TypeBuilder, R>
   }
 
   void forEach(void f(String name, MemberBuilder builder)) {
-    members.forEach(f);
+    scope.forEach(f);
   }
 
   /// Don't use for scope lookup. Only use when an element is known to exist
   /// (and isn't a setter).
   MemberBuilder operator [](String name) {
     // TODO(ahe): Rename this to getLocalMember.
-    return members[name] ?? internalError("Not found: '$name'.");
+    return scope.local[name] ?? internalError("Not found: '$name'.");
   }
 
   void addCompileTimeError(int charOffset, String message) {