sdk/pkg/front_end/test/incremental_expectations.dart

// Copyright (c) 2017, 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:convert" show JsonDecoder, JsonEncoder;

const JsonEncoder json = const JsonEncoder.withIndent("  ");

List<IncrementalExpectation> extractJsonExpectations(String source) {
  return new List<IncrementalExpectation>.from(
    source
        .split("\n")
        .where((l) => l.startsWith("<<<< ") || l.startsWith("==== "))
        .map((l) => l.substring("<<<< ".length))
        .map((l) => new IncrementalExpectation.fromJson(l)),
  );
}

class IncrementalExpectation {
  final List<String> messages;

  final bool commitChangesShouldFail;

  final bool hasCompileTimeError;

  const new(
    this.messages, {
    this.commitChangesShouldFail = false,
    this.hasCompileTimeError = false,
  });

  factory fromJson(String json) {
    var data = const JsonDecoder().convert(json);
    if (data is String) {
      data = <String>[data];
    }
    if (data is List) {
      return new IncrementalExpectation(data.cast<String>());
    }
    return new IncrementalExpectation(
      extractMessages(data),
      commitChangesShouldFail: extractCommitChangesShouldFail(data),
      hasCompileTimeError: extractHasCompileTimeError(data),
    );
  }

  dynamic toJson() {
    if (!commitChangesShouldFail && !hasCompileTimeError) {
      return messages.length == 1 ? messages.first : messages;
    }
    Map<String, dynamic> result = <String, dynamic>{"messages": messages};
    if (commitChangesShouldFail) {
      result['commitChangesShouldFail'] = 1;
    }
    if (hasCompileTimeError) {
      result['hasCompileTimeError'] = 1;
    }
    return result;
  }

  @override
  String toString() {
    return """
IncrementalExpectation(
    ${json.convert(messages)},
    commitChangesShouldFail: $commitChangesShouldFail,
    hasCompileTimeError: $hasCompileTimeError)""";
  }

  static List<String> extractMessages(Map<String, dynamic> json) {
    return new List<String>.from(json["messages"]);
  }

  static bool extractCommitChangesShouldFail(Map<String, dynamic> json) {
    return json["commitChangesShouldFail"] == 1;
  }

  static bool extractHasCompileTimeError(Map<String, dynamic> json) {
    return json["hasCompileTimeError"] == 1;
  }
}