packages/flutter_tools/test/general.shard/web/web_expression_compiler_test.dart

// Copyright 2014 The Flutter Authors. 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:dwds/dwds.dart';
import 'package:file/memory.dart';
import 'package:flutter_tools/src/base/file_system.dart';
import 'package:flutter_tools/src/compile.dart';
import 'package:flutter_tools/src/isolated/devfs_web.dart';
import 'package:test/fake.dart';

import '../../src/common.dart';

void main() {
  late FileSystem fileSystem;

  setUp(() {
    fileSystem = MemoryFileSystem.test();
  });

  testWithoutContext('WebExpressionCompiler handles successful expression compilation', () async {
    fileSystem.file('compilerOutput').writeAsStringSync('a');
    final ResidentCompiler residentCompiler = FakeResidentCompiler(const CompilerOutput('compilerOutput', 0, <Uri>[]));
    final ExpressionCompiler expressionCompiler = WebExpressionCompiler(residentCompiler, fileSystem: fileSystem);

    final ExpressionCompilationResult result =
      await expressionCompiler.compileExpressionToJs(
        '', '', 1, 1, <String, String>{}, <String, String>{}, '', '');

    expectResult(result, false, 'a');
  });

  testWithoutContext('WebExpressionCompiler handles compilation error', () async {
    fileSystem.file('compilerOutput').writeAsStringSync('Error: a');
    final ResidentCompiler residentCompiler = FakeResidentCompiler(const CompilerOutput('compilerOutput', 1, <Uri>[]));
    final ExpressionCompiler expressionCompiler = WebExpressionCompiler(residentCompiler, fileSystem: fileSystem);

    final ExpressionCompilationResult result =
      await expressionCompiler.compileExpressionToJs(
        '', '', 1, 1, <String, String>{}, <String, String>{}, '', '');

    expectResult(result, true, 'Error: a');
  });

  testWithoutContext('WebExpressionCompiler handles internal error', () async {
    final ResidentCompiler residentCompiler = FakeResidentCompiler(null);
    final ExpressionCompiler expressionCompiler = WebExpressionCompiler(residentCompiler, fileSystem: fileSystem);

    final ExpressionCompilationResult result =
      await expressionCompiler.compileExpressionToJs(
        '', '', 1, 1, <String, String>{}, <String, String>{}, '', 'a');

    expectResult(result, true, "InternalError: frontend server failed to compile 'a'");
  });
}

void expectResult(ExpressionCompilationResult result, bool isError, String value) {
  expect(result,
    const TypeMatcher<ExpressionCompilationResult>()
      .having((ExpressionCompilationResult instance) => instance.isError, 'isError', isError)
      .having((ExpressionCompilationResult instance) => instance.result, 'result', value));
}

class FakeResidentCompiler extends Fake implements ResidentCompiler {
  FakeResidentCompiler(this.output);

  final CompilerOutput? output;

  @override
  Future<CompilerOutput?> compileExpressionToJs(
    String libraryUri,
    int line,
    int column,
    Map<String, String> jsModules,
    Map<String, String> jsFrameValues,
    String moduleName,
    String expression,
  ) async {
    return output;
  }
}