Fasta kernel builders.

pkg/fasta/lib/src/kernel/kernel_enum_builder.dart

+// Copyright (c) 2016, 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 fasta.kernel_enum_builder;
+
+import 'package:kernel/ast.dart' show
+    Arguments,
+    AsyncMarker,
+    Class,
+    Constructor,
+    ConstructorInvocation,
+    DirectPropertyGet,
+    Expression,
+    Field,
+    FieldInitializer,
+    IntLiteral,
+    InterfaceType,
+    ListLiteral,
+    MapEntry,
+    MapLiteral,
+    MethodInvocation,
+    Name,
+    ProcedureKind,
+    ReturnStatement,
+    StaticGet,
+    StringLiteral,
+    ThisExpression,
+    VariableGet;
+
+import '../errors.dart' show
+    inputError;
+
+import '../modifier.dart' show
+    constMask,
+    finalMask,
+    staticMask;
+
+import "../source/source_class_builder.dart" show
+    SourceClassBuilder;
+
+import 'kernel_builder.dart' show
+    Builder,
+    EnumBuilder,
+    FormalParameterBuilder,
+    KernelConstructorBuilder,
+    KernelFieldBuilder,
+    KernelFormalParameterBuilder,
+    KernelInterfaceTypeBuilder,
+    KernelLibraryBuilder,
+    KernelProcedureBuilder,
+    KernelTypeBuilder,
+    LibraryBuilder,
+    MemberBuilder,
+    MetadataBuilder;
+
+class KernelEnumBuilder extends SourceClassBuilder
+    implements EnumBuilder<KernelTypeBuilder, InterfaceType> {
+  final List<String> constants;
+
+  final MapLiteral toStringMap;
+
+  final KernelTypeBuilder intType;
+
+  final KernelTypeBuilder stringType;
+
+  KernelEnumBuilder.internal(List<MetadataBuilder> metadata, String name,
+      Map<String, Builder> members, List<KernelTypeBuilder> types, Class cls,
+      this.constants, this.toStringMap, this.intType, this.stringType,
+      LibraryBuilder parent)
+      : super(metadata, 0, name, null, null, null, members, types, parent, null,
+          cls);
+
+  factory KernelEnumBuilder(List<MetadataBuilder> metadata, String name,
+      List<String> constants, LibraryBuilder parent) {
+    constants ??= const <String>[];
+    // TODO(ahe): These types shouldn't be looked up in scope, they come
+    // directly from dart:core.
+    KernelTypeBuilder objectType =
+        new KernelInterfaceTypeBuilder("Object", null);
+    KernelTypeBuilder intType =
+        new KernelInterfaceTypeBuilder("int", null);
+    KernelTypeBuilder stringType =
+        new KernelInterfaceTypeBuilder("String", null);
+    List<KernelTypeBuilder> types = <KernelTypeBuilder>[
+        objectType,
+        intType,
+        stringType];
+    Class cls = new Class(name: name);
+    Map<String, Builder> members = <String, Builder>{};
+    KernelInterfaceTypeBuilder selfType = new KernelInterfaceTypeBuilder(
+        name, null);
+    KernelTypeBuilder listType =
+        new KernelInterfaceTypeBuilder("List", <KernelTypeBuilder>[selfType]);
+    types.add(listType);
+
+    /// From Dart Programming Language Specification 4th Edition/December 2015:
+    ///     metadata class E {
+    ///       final int index;
+    ///       const E(this.index);
+    ///       static const E id0 = const E(0);
+    ///       ...
+    ///       static const E idn-1 = const E(n - 1);
+    ///       static const List<E> values = const <E>[id0, ..., idn-1];
+    ///       String toString() => { 0: ‘E.id0’, . . ., n-1: ‘E.idn-1’}[index]
+    ///     }
+    members["index"] =
+        new KernelFieldBuilder(null, intType, "index", finalMask);
+    KernelConstructorBuilder constructorBuilder = new KernelConstructorBuilder(
+        null, constMask, null, "", null, <FormalParameterBuilder>[
+            new KernelFormalParameterBuilder(null, 0, intType, "index", true)]);
+    members[""] = constructorBuilder;
+    int index = 0;
+    List<MapEntry> toStringEntries = <MapEntry>[];
+    KernelFieldBuilder valuesBuilder = new KernelFieldBuilder(null, listType,
+        "values", constMask | staticMask);
+    members["values"] = valuesBuilder;
+    KernelProcedureBuilder toStringBuilder = new KernelProcedureBuilder(null, 0,
+        stringType, "toString", null, null, AsyncMarker.Sync,
+        ProcedureKind.Method);
+    members["toString"] = toStringBuilder;
+    String className = name;
+    for (String name in constants) {
+      if (members.containsKey(name)) {
+        inputError(null, null, "Duplicated name: $name");
+        continue;
+      }
+      KernelFieldBuilder fieldBuilder =
+          new KernelFieldBuilder(null, selfType, name, constMask | staticMask);
+      members[name] = fieldBuilder;
+      toStringEntries.add(new MapEntry(
+              new IntLiteral(index), new StringLiteral("$className.$name")));
+      index++;
+    }
+    MapLiteral toStringMap = new MapLiteral(toStringEntries, isConst: true);
+    KernelEnumBuilder enumBuilder = new KernelEnumBuilder.internal(metadata,
+        name, members, types, cls, constants, toStringMap, intType, stringType,
+        parent);
+    members.forEach((String name, MemberBuilder builder) {
+      builder.parent = enumBuilder;
+    });
+    selfType.builder = enumBuilder;
+    return enumBuilder;
+  }
+
+  InterfaceType buildType(List<KernelTypeBuilder> arguments) {
+    return cls.rawType;
+  }
+
+  Class build(KernelLibraryBuilder libraryBuilder) {
+    if (constants.isEmpty) {
+      libraryBuilder.addCompileTimeError(
+          -1, "An enum declaration can't be empty.");
+    }
+    toStringMap.keyType = intType.build();
+    toStringMap.valueType = stringType.build();
+    KernelFieldBuilder indexFieldBuilder = members["index"];
+    Field indexField = indexFieldBuilder.build(libraryBuilder.library);
+    KernelProcedureBuilder toStringBuilder = members["toString"];
+    toStringBuilder.body = new ReturnStatement(
+        new MethodInvocation(toStringMap, new Name("[]"),
+            new Arguments(<Expression>[
+                    new DirectPropertyGet(new ThisExpression(), indexField)])));
+    List<Expression> values = <Expression>[];
+    for (String name in constants) {
+      KernelFieldBuilder builder = members[name];
+      values.add(new StaticGet(builder.build(libraryBuilder.library)));
+    }
+    KernelFieldBuilder valuesBuilder = members["values"];
+    valuesBuilder.build(libraryBuilder.library);
+    valuesBuilder.initializer =
+        new ListLiteral(values, typeArgument: cls.rawType, isConst: true);
+    KernelConstructorBuilder constructorBuilder = members[""];
+    Constructor constructor = constructorBuilder.build(libraryBuilder.library);
+    constructor.initializers.insert(0, new FieldInitializer(indexField,
+            new VariableGet(constructor.function.positionalParameters.single))
+        ..parent = constructor);
+    int index = 0;
+    for (String constant in constants) {
+      KernelFieldBuilder field = members[constant];
+      field.build(libraryBuilder.library);
+      Arguments arguments =
+          new Arguments(<Expression>[new IntLiteral(index++)]);
+      field.initializer =
+          new ConstructorInvocation(constructor, arguments, isConst: true);
+    }
+    return super.build(libraryBuilder);
+  }
+
+  Builder findConstructorOrFactory(String name) => null;
+}