Support external implementations of FileSpan.
Previously, several FileSpan methods assumed that all FileSpans were
implementations of this package's FileSpan class. However, this may not
always be true. It can be useful to create FileSpans without first
creating a SourceFile when efficient representations of line/column
information are already available, and the user doesn't want to eagerly
do the parsing necessary to create a full SourceFile.
This also fixes an inconsistency between FileSpan.== and
FileSpan.hashCode.
R=sigmund@google.com
Review URL: https://codereview.chromium.org//1298093002 .
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 51b0fea..8ca9e5c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+# 1.1.3
+
+* `FileSpan.compareTo`, `FileSpan.==`, `FileSpan.union`, and `FileSpan.expand`
+ no longer throw exceptions for external implementations of `FileSpan`.
+
+* `FileSpan.hashCode` now fully agrees with `FileSpan.==`.
+
# 1.1.2
* Fixed validation in `SourceSpanWithContext` to allow multiple occurrences of
diff --git a/lib/src/file.dart b/lib/src/file.dart
index 4b4e026..c180929 100644
--- a/lib/src/file.dart
+++ b/lib/src/file.dart
@@ -7,9 +7,6 @@
import 'dart:math' as math;
import 'dart:typed_data';
-import 'package:path/path.dart' as p;
-
-import 'colors.dart' as colors;
import 'location.dart';
import 'span.dart';
import 'span_mixin.dart';
@@ -74,7 +71,7 @@
/// 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);
+ return new _FileSpan(this, start, end);
}
/// Returns a location in [this] at [offset].
@@ -173,7 +170,7 @@
}
}
- FileSpan pointSpan() => new FileSpan._(file, offset, offset);
+ FileSpan pointSpan() => new _FileSpan(file, offset, offset);
}
/// A [SourceSpan] within a [SourceFile].
@@ -184,8 +181,23 @@
/// [FileSpan.union] will return a [FileSpan] if possible.
///
/// A [FileSpan] can be created using [SourceFile.span].
-class FileSpan extends SourceSpanMixin implements SourceSpanWithContext {
+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.
@@ -208,7 +220,7 @@
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) {
+ _FileSpan(this.file, this._start, this._end) {
if (_end < _start) {
throw new ArgumentError('End $_end must come after start $_start.');
} else if (_end > file.length) {
@@ -220,9 +232,9 @@
}
int compareTo(SourceSpan other) {
- if (other is! FileSpan) return super.compareTo(other);
+ if (other is! _FileSpan) return super.compareTo(other);
- FileSpan otherFile = other;
+ _FileSpan otherFile = other;
var result = _start.compareTo(otherFile._start);
return result == 0 ? _end.compareTo(otherFile._end) : result;
}
@@ -230,7 +242,7 @@
SourceSpan union(SourceSpan other) {
if (other is! FileSpan) return super.union(other);
- var span = expand(other);
+ _FileSpan span = expand(other);
var beginSpan = span._start == _start ? this : other;
var endSpan = span._end == _end ? this : other;
@@ -243,13 +255,14 @@
bool operator ==(other) {
if (other is! FileSpan) return super == other;
+ if (other is! _FileSpan) {
+ return super == other && sourceUrl == other.sourceUrl;
+ }
+
return _start == other._start && _end == other._end &&
sourceUrl == other.sourceUrl;
}
- int get hashCode => _start.hashCode + 5 * _end.hashCode +
- 7 * sourceUrl.hashCode;
-
/// Returns a new span that covers both [this] and [other].
///
/// Unlike [union], [other] may be disjoint from [this]. If it is, the text
@@ -260,8 +273,14 @@
" \"${other.sourceUrl}\" don't match.");
}
- var start = math.min(this._start, other._start);
- var end = math.max(this._end, other._end);
- return new FileSpan._(file, start, end);
+ 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);
+ }
}
}
diff --git a/pubspec.yaml b/pubspec.yaml
index 8f69deb..daee3f6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
name: source_span
-version: 1.1.3-dev
+version: 1.1.3
author: Dart Team <misc@dartlang.org>
description: A library for identifying source spans and locations.
homepage: http://github.com/dart-lang/source_span
