pkgs/jnigen/lib/src/util/dart_executable.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 'dart:io';
import 'package:path/path.dart' as p;

/// The path to the Dart executable.
///
/// This is usually just Platform.resolvedExecutable. But when running flutter
/// tests, the resolvedExecutable will be flutter_tester, and Dart will be in a
/// directory a few levels up from it.
final String dartExecutable = _findDart();

String? _findDartInternal(String executablePath) {
  var path = executablePath;
  if (p.basenameWithoutExtension(path) == 'dart') return path;
  final dartExe = 'dart${p.extension(path)}';
  while (path.isNotEmpty) {
    path = p.dirname(path);
    final dartPath = p.normalize(p.join(path, dartExe));
    if (File(dartPath).existsSync()) return dartPath;
    final parent = p.dirname(path);
    if (parent == path) break;
  }
  return null;
}

String _findDart() {
  final path = _findDartInternal(Platform.resolvedExecutable) ??
      _findDartInternal(Platform.executable);
  if (path == null) {
    throw Exception(
      "Couldn't find Dart executable near ${Platform.resolvedExecutable} "
      'or ${Platform.executable}',
    );
  }
  return path;
}