pkg/front_end/lib/src/fasta/builder/procedure_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.procedure_builder;

// Note: we're deliberately using AsyncMarker and ProcedureKind from kernel
// outside the kernel-specific builders. This is simpler than creating
// additional enums.
import 'package:kernel/ast.dart' show AsyncMarker, ProcedureKind;

import 'builder.dart'
    show
        Declaration,
        FormalParameterBuilder,
        LibraryBuilder,
        MemberBuilder,
        MetadataBuilder,
        Scope,
        TypeBuilder,
        TypeVariableBuilder;

abstract class ProcedureBuilder<T extends TypeBuilder> extends MemberBuilder {
  final List<MetadataBuilder> metadata;

  final int modifiers;

  final T returnType;

  final String name;

  final List<TypeVariableBuilder> typeVariables;

  final List<FormalParameterBuilder> formals;

  ProcedureBuilder(
      this.metadata,
      this.modifiers,
      this.returnType,
      this.name,
      this.typeVariables,
      this.formals,
      LibraryBuilder compilationUnit,
      int charOffset)
      : super(compilationUnit, charOffset);

  String get debugName => "ProcedureBuilder";

  AsyncMarker get asyncModifier;

  ProcedureKind get kind;

  bool get isConstructor => false;

  bool get isRegularMethod => identical(ProcedureKind.Method, kind);

  bool get isGetter => identical(ProcedureKind.Getter, kind);

  bool get isSetter => identical(ProcedureKind.Setter, kind);

  bool get isOperator => identical(ProcedureKind.Operator, kind);

  bool get isFactory => identical(ProcedureKind.Factory, kind);

  void set body(covariant statement);

  /// This is the formal parameter scope as specified in the Dart Programming
  /// Language Specifiction, 4th ed, section 9.2.
  Scope computeFormalParameterScope(Scope parent) {
    if (formals == null) return parent;
    Map<String, Declaration> local = <String, Declaration>{};
    for (FormalParameterBuilder formal in formals) {
      if (!isConstructor || !formal.hasThis) {
        local[formal.name] = formal;
      }
    }
    return new Scope(local, null, parent, "formal parameter",
        isModifiable: false);
  }

  Scope computeFormalParameterInitializerScope(Scope parent) {
    // From
    // [dartLangSpec.tex](../../../../../../docs/language/dartLangSpec.tex) at
    // revision 94b23d3b125e9d246e07a2b43b61740759a0dace:
    //
    // When the formal parameter list of a non-redirecting generative
    // constructor contains any initializing formals, a new scope is
    // introduced, the _formal parameter initializer scope_, which is the
    // current scope of the initializer list of the constructor, and which is
    // enclosed in the scope where the constructor is declared.  Each
    // initializing formal in the formal parameter list introduces a final
    // local variable into the formal parameter initializer scope, but not into
    // the formal parameter scope; every other formal parameter introduces a
    // local variable into both the formal parameter scope and the formal
    // parameter initializer scope.

    if (formals == null) return parent;
    Map<String, Declaration> local = <String, Declaration>{};
    for (FormalParameterBuilder formal in formals) {
      local[formal.name] = formal.forFormalParameterInitializerScope();
    }
    return new Scope(local, null, parent, "formal parameter initializer",
        isModifiable: false);
  }

  /// This scope doesn't correspond to any scope specified in the Dart
  /// Programming Language Specifiction, 4th ed. It's an unspecified extension
  /// to support generic methods.
  Scope computeTypeParameterScope(Scope parent) {
    if (typeVariables == null) return parent;
    Map<String, Declaration> local = <String, Declaration>{};
    for (TypeVariableBuilder variable in typeVariables) {
      local[variable.name] = variable;
    }
    return new Scope(local, null, parent, "type parameter",
        isModifiable: false);
  }

  FormalParameterBuilder getFormal(String name) {
    for (FormalParameterBuilder formal in formals) {
      if (formal.name == name) return formal;
    }
    return null;
  }
}