Roll Observatory packages and add a roll script

source_span/lib/src/file.dart

Index: source_span/lib/src/file.dart
diff --git a/source_span/lib/src/file.dart b/source_span/lib/src/file.dart
deleted file mode 100644
index 95fa92ca3b12a7586ca4d3e995c9407039cd69f1..0000000000000000000000000000000000000000
--- a/source_span/lib/src/file.dart
+++ /dev/null
@@ -1,355 +0,0 @@
-// 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.file;
-
-import 'dart:math' as math;
-import 'dart:typed_data';
-
-import 'location.dart';
-import 'location_mixin.dart';
-import 'span.dart';
-import 'span_mixin.dart';
-import 'span_with_context.dart';
-
-// Constants to determine end-of-lines.
-const int _LF = 10;
-const int _CR = 13;
-
-/// A class representing a source file.
-///
-/// This doesn't necessarily have to correspond to a file on disk, just a chunk
-/// of text usually with a URL associated with it.
-class SourceFile {
-  /// The URL where the source file is located.
-  ///
-  /// This may be null, indicating that the URL is unknown or unavailable.
-  final Uri url;
-
-  /// An array of offsets for each line beginning in the file.
-  ///
-  /// Each offset refers to the first character *after* the newline. If the
-  /// source file has a trailing newline, the final offset won't actually be in
-  /// the file.
-  final _lineStarts = <int>[0];
-
-  /// The code points of the characters in the file.
-  final Uint32List _decodedChars;
-
-  /// The length of the file in characters.
-  int get length => _decodedChars.length;
-
-  /// The number of lines in the file.
-  int get lines => _lineStarts.length;
-
-  /// The line that the offset fell on the last time [getLine] was called.
-  ///
-  /// In many cases, sequential calls to getLine() are for nearby, usually
-  /// increasing offsets. In that case, we can find the line for an offset
-  /// quickly by first checking to see if the offset is on the same line as the
-  /// previous result.
-  int _cachedLine;
-
-  /// Creates a new source file from [text].
-  ///
-  /// [url] may be either a [String], a [Uri], or `null`.
-  SourceFile(String text, {url})
-      : this.decoded(text.runes, url: url);
-
-  /// Creates a new source file from a list of decoded characters.
-  ///
-  /// [url] may be either a [String], a [Uri], or `null`.
-  SourceFile.decoded(Iterable<int> decodedChars, {url})
-      : url = url is String ? Uri.parse(url) : url,
-        _decodedChars = new Uint32List.fromList(decodedChars.toList()) {
-    for (var i = 0; i < _decodedChars.length; i++) {
-      var c = _decodedChars[i];
-      if (c == _CR) {
-        // Return not followed by newline is treated as a newline
-        var j = i + 1;
-        if (j >= _decodedChars.length || _decodedChars[j] != _LF) c = _LF;
-      }
-      if (c == _LF) _lineStarts.add(i + 1);
-    }
-  }
-
-  /// Returns a span in [this] from [start] to [end] (exclusive).
-  ///
-  /// If [end] isn't passed, it defaults to the end of the file.
-  FileSpan span(int start, [int end]) {
-    if (end == null) end = length - 1;
-    return new _FileSpan(this, start, end);
-  }
-
-  /// Returns a location in [this] at [offset].
-  FileLocation location(int offset) => new FileLocation._(this, offset);
-
-  /// Gets the 0-based line corresponding to [offset].
-  int getLine(int offset) {
-    if (offset < 0) {
-      throw new RangeError("Offset may not be negative, was $offset.");
-    } else if (offset > length) {
-      throw new RangeError("Offset $offset must not be greater than the number "
-          "of characters in the file, $length.");
-    }
-
-    if (offset < _lineStarts.first) return -1;
-    if (offset >= _lineStarts.last) return _lineStarts.length - 1;
-
-    if (_isNearCachedLine(offset)) return _cachedLine;
-
-    _cachedLine = _binarySearch(offset) - 1;
-    return _cachedLine;
-  }
-
-  /// Returns `true` if [offset] is near [_cachedLine].
-  ///
-  /// Checks on [_cachedLine] and the next line. If it's on the next line, it
-  /// updates [_cachedLine] to point to that.
-  bool _isNearCachedLine(int offset) {
-    if (_cachedLine == null) return false;
-
-    // See if it's before the cached line.
-    if (offset < _lineStarts[_cachedLine]) return false;
-
-    // See if it's on the cached line.
-    if (_cachedLine >= _lineStarts.length - 1 ||
-        offset < _lineStarts[_cachedLine + 1]) {
-      return true;
-    }
-
-    // See if it's on the next line.
-    if (_cachedLine >= _lineStarts.length - 2 ||
-        offset < _lineStarts[_cachedLine + 2]) {
-      _cachedLine++;
-      return true;
-    }
-
-    return false;
-  }
-
-  /// Binary search through [_lineStarts] to find the line containing [offset].
-  ///
-  /// Returns the index of the line in [_lineStarts].
-  int _binarySearch(int offset) {
-    int min = 0;
-    int max = _lineStarts.length - 1;
-    while (min < max) {
-      var half = min + ((max - min) ~/ 2);
-      if (_lineStarts[half] > offset) {
-        max = half;
-      } else {
-        min = half + 1;
-      }
-    }
-
-    return max;
-  }
-
-  /// Gets the 0-based column corresponding to [offset].
-  ///
-  /// If [line] is passed, it's assumed to be the line containing [offset] and
-  /// is used to more efficiently compute the column.
-  int getColumn(int offset, {int line}) {
-    if (offset < 0) {
-      throw new RangeError("Offset may not be negative, was $offset.");
-    } else if (offset > length) {
-      throw new RangeError("Offset $offset must be not be greater than the "
-          "number of characters in the file, $length.");
-    }
-
-    if (line == null) {
-      line = getLine(offset);
-    } else if (line < 0) {
-      throw new RangeError("Line may not be negative, was $line.");
-    } else if (line >= lines) {
-      throw new RangeError("Line $line must be less than the number of "
-          "lines in the file, $lines.");
-    }
-
-    var lineStart = _lineStarts[line];
-    if (lineStart > offset) {
-      throw new RangeError("Line $line comes after offset $offset.");
-    }
-
-    return offset - lineStart;
-  }
-
-  /// Gets the offset for a [line] and [column].
-  ///
-  /// [column] defaults to 0.
-  int getOffset(int line, [int column]) {
-    if (column == null) column = 0;
-
-    if (line < 0) {
-      throw new RangeError("Line may not be negative, was $line.");
-    } else if (line >= lines) {
-      throw new RangeError("Line $line must be less than the number of "
-          "lines in the file, $lines.");
-    } else if (column < 0) {
-      throw new RangeError("Column may not be negative, was $column.");
-    }
-
-    var result = _lineStarts[line] + column;
-    if (result > length ||
-        (line + 1 < lines && result >= _lineStarts[line + 1])) {
-      throw new RangeError("Line $line doesn't have $column columns.");
-    }
-
-    return result;
-  }
-
-  /// Returns the text of the file from [start] to [end] (exclusive).
-  ///
-  /// If [end] isn't passed, it defaults to the end of the file.
-  String getText(int start, [int end]) =>
-      new String.fromCharCodes(_decodedChars.sublist(start, end));
-}
-
-/// A [SourceLocation] within a [SourceFile].
-///
-/// Unlike the base [SourceLocation], [FileLocation] lazily computes its line
-/// and column values based on its offset and the contents of [file].
-///
-/// A [FileLocation] can be created using [SourceFile.location].
-class FileLocation extends SourceLocationMixin implements SourceLocation {
-  /// The [file] that [this] belongs to.
-  final SourceFile file;
-
-  final int offset;
-  Uri get sourceUrl => file.url;
-  int get line => file.getLine(offset);
-  int get column => file.getColumn(offset);
-
-  FileLocation._(this.file, this.offset) {
-    if (offset < 0) {
-      throw new RangeError("Offset may not be negative, was $offset.");
-    } else if (offset > file.length) {
-      throw new RangeError("Offset $offset must not be greater than the number "
-          "of characters in the file, ${file.length}.");
-    }
-  }
-
-  FileSpan pointSpan() => new _FileSpan(file, offset, offset);
-}
-
-/// A [SourceSpan] within a [SourceFile].
-///
-/// Unlike the base [SourceSpan], [FileSpan] lazily computes its line and column
-/// values based on its offset and the contents of [file]. [FileSpan.message] is
-/// also able to provide more context then [SourceSpan.message], and
-/// [FileSpan.union] will return a [FileSpan] if possible.
-///
-/// A [FileSpan] can be created using [SourceFile.span].
-abstract class FileSpan implements SourceSpanWithContext {
-  /// The [file] that [this] belongs to.
-  SourceFile get file;
-
-  /// Returns a new span that covers both [this] and [other].
-  ///
-  /// Unlike [union], [other] may be disjoint from [this]. If it is, the text
-  /// between the two will be covered by the returned span.
-  FileSpan expand(FileSpan other);
-}
-
-/// The implementation of [FileSpan].
-///
-/// This is split into a separate class so that `is _FileSpan` checks can be run
-/// to make certain operations more efficient. If we used `is FileSpan`, that
-/// would break if external classes implemented the interface.
-class _FileSpan extends SourceSpanMixin implements FileSpan {
-  final SourceFile file;
-
-  /// The offset of the beginning of the span.
-  ///
-  /// [start] is lazily generated from this to avoid allocating unnecessary
-  /// objects.
-  final int _start;
-
-  /// The offset of the end of the span.
-  ///
-  /// [end] is lazily generated from this to avoid allocating unnecessary
-  /// objects.
-  final int _end;
-
-  Uri get sourceUrl => file.url;
-  int get length => _end - _start;
-  FileLocation get start => new FileLocation._(file, _start);
-  FileLocation get end => new FileLocation._(file, _end);
-  String get text => file.getText(_start, _end);
-  String get context => file.getText(file.getOffset(start.line),
-      end.line == file.lines - 1 ? null : file.getOffset(end.line + 1));
-
-  _FileSpan(this.file, this._start, this._end) {
-    if (_end < _start) {
-      throw new ArgumentError('End $_end must come after start $_start.');
-    } else if (_end > file.length) {
-      throw new RangeError("End $_end must not be greater than the number "
-          "of characters in the file, ${file.length}.");
-    } else if (_start < 0) {
-      throw new RangeError("Start may not be negative, was $_start.");
-    }
-  }
-
-  int compareTo(SourceSpan other) {
-    if (other is! _FileSpan) return super.compareTo(other);
-
-    _FileSpan otherFile = other;
-    var result = _start.compareTo(otherFile._start);
-    return result == 0 ? _end.compareTo(otherFile._end) : result;
-  }
-
-  SourceSpan union(SourceSpan other) {
-    if (other is! FileSpan) return super.union(other);
-
-    
-    _FileSpan span = expand(other);
-
-    if (other is _FileSpan) {
-      if (this._start > other._end || other._start > this._end) {
-        throw new ArgumentError("Spans $this and $other are disjoint.");
-      }
-    } else {
-      if (this._start > other.end.offset || other.start.offset > this._end) {
-        throw new ArgumentError("Spans $this and $other are disjoint.");
-      }
-    }
-
-    return span;
-  }
-
-  bool operator ==(other) {
-    if (other is! FileSpan) return super == other;
-    if (other is! _FileSpan) {
-      return super == other && sourceUrl == other.sourceUrl;
-    }
-
-    return _start == other._start && _end == other._end &&
-        sourceUrl == other.sourceUrl;
-  }
-
-  // Eliminates dart2js warning about overriding `==`, but not `hashCode`
-  int get hashCode => super.hashCode;
-
-  /// Returns a new span that covers both [this] and [other].
-  ///
-  /// Unlike [union], [other] may be disjoint from [this]. If it is, the text
-  /// between the two will be covered by the returned span.
-  FileSpan expand(FileSpan other) {
-    if (sourceUrl != other.sourceUrl) {
-      throw new ArgumentError("Source URLs \"${sourceUrl}\" and "
-          " \"${other.sourceUrl}\" don't match.");
-    }
-
-    if (other is _FileSpan) {
-      var start = math.min(this._start, other._start);
-      var end = math.max(this._end, other._end);
-      return new _FileSpan(file, start, end);
-    } else {
-      var start = math.min(this._start, other.start.offset);
-      var end = math.max(this._end, other.end.offset);
-      return new _FileSpan(file, start, end);
-    }
-  }
-}