pkg/dart2wasm/lib/dev/runtime.dart

// Copyright (c) 2026, 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.

import 'package:wasm_builder/wasm_builder.dart' as w;

const w.ValueType _jsString = w.RefType.extern(nullable: false);
const w.ValueType _funcRef = w.RefType.func(nullable: false);
const w.ValueType _eqRef = w.RefType.eq(nullable: false);

/// The Wasm dev runtime (`pkg/wasm_dev_rt`) API for [module].
class DevRuntime {
  final w.ModuleBuilder module;

  late final w.BaseFunction print = _import('print', [_jsString]);
  late final w.BaseFunction staticId = _import(
    'staticId',
    [_jsString],
    [w.NumType.i32],
  );
  late final w.BaseFunction defineStatic = _import('defineStatic', [
    w.NumType.i32,
    _funcRef,
  ]);
  late final w.BaseFunction lookupStatic = _import(
    'lookupStatic',
    [w.NumType.i32],
    [_funcRef],
  );
  late final w.BaseFunction classId = _import(
    'classId',
    [_jsString],
    [w.NumType.i32],
  );
  late final w.BaseFunction defineClassSupers = _import('defineClassSupers', [
    w.NumType.i32,
    w.NumType.i32,
  ]);
  late final w.BaseFunction instanceMemberId = _import(
    'instanceMemberId',
    [_jsString],
    [w.NumType.i32],
  );
  late final w.BaseFunction shapeId = _import(
    'shapeId',
    [_jsString],
    [w.NumType.i32],
  );
  late final w.BaseFunction startInstanceMemberDefinitions = _import(
    'startInstanceMemberDefinitions',
    [w.NumType.i32],
  );
  late final w.BaseFunction defineInstanceMember = _import(
    'defineInstanceMember',
    [w.NumType.i32, w.NumType.i32, w.NumType.i32, _funcRef],
  );
  late final w.BaseFunction endInstanceMemberDefinitions = _import(
    'endInstanceMemberDefinitions',
    [w.NumType.i32],
  );
  late final w.BaseFunction findTarget = _import(
    'findTarget',
    [w.NumType.i32, w.NumType.i32, w.NumType.i32],
    [_funcRef],
  );
  late final w.BaseFunction defaultValueSentinel = _import(
    'defaultValueSentinel',
    [_eqRef],
    [_eqRef],
  );

  DevRuntime(this.module);

  /// Imports the function [name] exported by the runtime.
  w.BaseFunction _import(
    String name,
    List<w.ValueType> inputs, [
    List<w.ValueType> outputs = const [],
  ]) => module.functions.import(
    'wasm_dev_rt',
    name,
    module.types.defineFunction(inputs, outputs),
    'wasm_dev_rt.$name',
  );
}