prepareBridges method

Future<bool> prepareBridges(BridgeConfig config)

Generate bridges once for a project without running any script.

This method:

1. Deletes the existing binary to verify regeneration
2. Generates bridges using the in-memory generator
3. Compiles the test runner to a native binary

Use this in setUpAll to prepare once, then call runScriptOnly for each test script.

Returns true if generation and compilation succeeded, false otherwise. On failure, the errors are stored and can be retrieved from subsequent runScriptOnly calls (which will return a failed result immediately).

Example:

setUpAll(() async {
  final ok = await tester.prepareBridges(config);
  expect(ok, isTrue, reason: 'Bridge generation failed');
});

test('feature X', () async {
  final result = await tester.runScriptOnly(config, 'test/x.dart');
  _expectSuccess(result, 'feature X');
});

Implementation

Future<bool> prepareBridges(BridgeConfig config) async {
  // Step 0: Ensure dependencies are resolved (package_config.json must exist
  // for the generator to resolve package: URIs in barrel files)
  final packageConfig = File(
    p.join(projectPath, '.dart_tool', 'package_config.json'),
  );
  if (!packageConfig.existsSync()) {
    final pubGetResult = await Process.run('dart', [
      'pub',
      'get',
    ], workingDirectory: projectPath);
    if (pubGetResult.exitCode != 0) {
      _lastGenerationErrors = [
        'dart pub get failed in $projectPath:',
        pubGetResult.stderr.toString(),
      ];
      return false;
    }
  }

  // Step 1: Delete existing binary to verify it gets regenerated
  final binaryFile = File(_binaryPath);
  if (binaryFile.existsSync()) {
    binaryFile.deleteSync();
  }

  // Step 2: Generate bridges
  final genResult = await _generateBridges(config);
  if (!genResult.isSuccess) {
    _lastGenerationErrors = genResult.errors;
    return false;
  }

  // Step 3: Compile the test runner to a native binary
  final runnerPath = _resolveRunnerPath(config);
  final compileResult = await Process.run('dart', [
    'compile',
    'exe',
    runnerPath,
    '-o',
    _binaryPath,
  ], workingDirectory: projectPath);

  if (compileResult.exitCode != 0) {
    _lastGenerationErrors = [
      'Failed to compile test runner:',
      compileResult.stderr.toString(),
    ];
    return false;
  }

  // Verify binary was created
  if (!File(_binaryPath).existsSync()) {
    _lastGenerationErrors = ['Compiled binary not found at $_binaryPath'];
    return false;
  }

  _lastGenerationErrors = null;
  return true;
}