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source_span/lib/src/span_with_context.dart

-// Copyright (c) 2014, 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 source_span.span_with_context;
-
-import 'location.dart';
-import 'span.dart';
-import 'utils.dart';
-
-/// A class that describes a segment of source text with additional context.
-class SourceSpanWithContext extends SourceSpanBase {
-  /// Text around the span, which includes the line containing this span.
-  final String context;
-
-  /// Creates a new span from [start] to [end] (exclusive) containing [text], in
-  /// the given [context].
-  ///
-  /// [start] and [end] must have the same source URL and [start] must come
-  /// before [end]. [text] must have a number of characters equal to the
-  /// distance between [start] and [end]. [context] must contain [text], and
-  /// [text] should start at `start.column` from the beginning of a line in
-  /// [context].
-  SourceSpanWithContext(
-      SourceLocation start, SourceLocation end, String text, this.context)
-      : super(start, end, text) {
-    if (!context.contains(text)) {
-      throw new ArgumentError(
-          'The context line "$context" must contain "$text".');
-    }
-
-    if (findLineStart(context, text, start.column) == null) {
-      throw new ArgumentError('The span text "$text" must start at '
-          'column ${start.column + 1} in a line within "$context".');
-    }
-  }
-}