| // Copyright (c) 2013, 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. |
| library error; |
| |
| import 'dart:collection'; |
| import 'dart:io'; |
| import 'dart:math' as math; |
| |
| import 'generated/error.dart'; |
| import 'generated/java_core.dart'; |
| import 'generated/source.dart'; |
| |
| /// The maximum line length when printing extracted source code when converting |
| /// an [AnalyzerError] to a string. |
| final _MAX_ERROR_LINE_LENGTH = 120; |
| |
| /// An error class that collects multiple [AnalyzerError]s that are emitted |
| /// during a single analysis. |
| class AnalyzerErrorGroup implements Exception { |
| /// The errors in this collection. |
| List<AnalyzerError> get errors => |
| new UnmodifiableListView<AnalyzerError>(_errors); |
| final List<AnalyzerError> _errors; |
| |
| AnalyzerErrorGroup(Iterable<AnalyzerError> errors) |
| : _errors = errors.toList(); |
| |
| /// Creates an [AnalyzerErrorGroup] from a list of lower-level |
| /// [AnalysisError]s. |
| AnalyzerErrorGroup.fromAnalysisErrors(Iterable<AnalysisError> errors) |
| : this(errors.map((e) => new AnalyzerError(e))); |
| |
| String get message => toString(); |
| String toString() => errors.join("\n"); |
| } |
| |
| /// A wrapper around [AnalysisError] that provides a more user-friendly string |
| /// representation. |
| class AnalyzerError implements Exception { |
| final AnalysisError error; |
| |
| AnalyzerError(this.error); |
| |
| String get message => toString(); |
| |
| String toString() { |
| var builder = new StringBuffer(); |
| var receiver = new _ContentReceiver(); |
| error.source.getContents(receiver); |
| var beforeError = receiver.result.substring(0, error.offset); |
| var lineNumber = "\n".allMatches(beforeError).length + 1; |
| builder.writeln("Error on line $lineNumber of ${error.source.fullName}: " |
| "${error.message}"); |
| |
| var errorLineIndex = beforeError.lastIndexOf("\n") + 1; |
| var errorEndOfLineIndex = receiver.result.indexOf("\n", error.offset); |
| if (errorEndOfLineIndex == -1) errorEndOfLineIndex = receiver.result.length; |
| var errorLine = receiver.result.substring( |
| errorLineIndex, errorEndOfLineIndex); |
| var errorColumn = error.offset - errorLineIndex; |
| var errorLength = error.length; |
| |
| // Ensure that the error line we display isn't too long. |
| if (errorLine.length > _MAX_ERROR_LINE_LENGTH) { |
| var leftLength = errorColumn; |
| var rightLength = errorLine.length - leftLength; |
| if (leftLength > _MAX_ERROR_LINE_LENGTH ~/ 2 && |
| rightLength > _MAX_ERROR_LINE_LENGTH ~/ 2) { |
| errorLine = "..." + errorLine.substring( |
| errorColumn - _MAX_ERROR_LINE_LENGTH ~/ 2 + 3, |
| errorColumn + _MAX_ERROR_LINE_LENGTH ~/ 2 - 3) |
| + "..."; |
| errorColumn = _MAX_ERROR_LINE_LENGTH ~/ 2; |
| } else if (rightLength > _MAX_ERROR_LINE_LENGTH ~/ 2) { |
| errorLine = errorLine.substring(0, _MAX_ERROR_LINE_LENGTH - 3) + "..."; |
| } else { |
| assert(leftLength > _MAX_ERROR_LINE_LENGTH ~/ 2); |
| errorColumn -= errorLine.length - _MAX_ERROR_LINE_LENGTH; |
| errorLine = "..." + errorLine.substring( |
| errorLine.length - _MAX_ERROR_LINE_LENGTH + 3, errorLine.length); |
| } |
| errorLength = math.min(errorLength, _MAX_ERROR_LINE_LENGTH - errorColumn); |
| } |
| builder.writeln(errorLine); |
| |
| for (var i = 0; i < errorColumn; i++) builder.write(" "); |
| for (var i = 0; i < errorLength; i++) builder.write("^"); |
| builder.writeln(); |
| |
| return builder.toString(); |
| } |
| } |
| |
| // A content receiver that collects all the content into a string. |
| class _ContentReceiver implements Source_ContentReceiver { |
| final _buffer = new StringBuffer(); |
| |
| String get result => _buffer.toString(); |
| |
| void accept(CharBuffer contents, _) => |
| _buffer.write(contents.subSequence(0, contents.length())); |
| |
| void accept2(String contents, _) => _buffer.write(contents); |
| } |