test/span_test.dart - source_span - Git at Google

 // 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.

 import 'package:source_span/source_span.dart';
 import 'package:source_span/src/colors.dart' as colors;
 import 'package:term_glyph/term_glyph.dart' as glyph;
 import 'package:test/test.dart';

 void main() {
   late bool oldAscii;

   setUpAll(() {
     oldAscii = glyph.ascii;
     glyph.ascii = true;
   });

   tearDownAll(() {
     glyph.ascii = oldAscii;
   });

   late SourceSpan span;
   setUp(() {
     span = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
         SourceLocation(12, sourceUrl: 'foo.dart'), 'foo bar');
   });

   group('errors', () {
     group('for new SourceSpan()', () {
       test('source URLs must match', () {
         final start = SourceLocation(0, sourceUrl: 'foo.dart');
         final end = SourceLocation(1, sourceUrl: 'bar.dart');
         expect(() => SourceSpan(start, end, '_'), throwsArgumentError);
       });

       test('end must come after start', () {
         final start = SourceLocation(1);
         final end = SourceLocation(0);
         expect(() => SourceSpan(start, end, '_'), throwsArgumentError);
       });

       test('text must be the right length', () {
         final start = SourceLocation(0);
         final end = SourceLocation(1);
         expect(() => SourceSpan(start, end, 'abc'), throwsArgumentError);
       });
     });

     group('for new SourceSpanWithContext()', () {
       test('context must contain text', () {
         final start = SourceLocation(2);
         final end = SourceLocation(5);
         expect(() => SourceSpanWithContext(start, end, 'abc', '--axc--'),
             throwsArgumentError);
       });

       test('text starts at start.column in context', () {
         final start = SourceLocation(3);
         final end = SourceLocation(5);
         expect(() => SourceSpanWithContext(start, end, 'abc', '--abc--'),
             throwsArgumentError);
       });

       test('text starts at start.column of line in multi-line context', () {
         final start = SourceLocation(4, line: 55, column: 3);
         final end = SourceLocation(7, line: 55, column: 6);
         expect(() => SourceSpanWithContext(start, end, 'abc', '\n--abc--'),
             throwsArgumentError);
         expect(() => SourceSpanWithContext(start, end, 'abc', '\n----abc--'),
             throwsArgumentError);
         expect(() => SourceSpanWithContext(start, end, 'abc', '\n\n--abc--'),
             throwsArgumentError);

         // However, these are valid:
         SourceSpanWithContext(start, end, 'abc', '\n---abc--');
         SourceSpanWithContext(start, end, 'abc', '\n\n---abc--');
       });

       test('text can occur multiple times in context', () {
         final start1 = SourceLocation(4, line: 55, column: 2);
         final end1 = SourceLocation(7, line: 55, column: 5);
         final start2 = SourceLocation(4, line: 55, column: 8);
         final end2 = SourceLocation(7, line: 55, column: 11);
         SourceSpanWithContext(start1, end1, 'abc', '--abc---abc--\n');
         SourceSpanWithContext(start1, end1, 'abc', '--abc--abc--\n');
         SourceSpanWithContext(start2, end2, 'abc', '--abc---abc--\n');
         SourceSpanWithContext(start2, end2, 'abc', '---abc--abc--\n');
         expect(
             () => SourceSpanWithContext(start1, end1, 'abc', '---abc--abc--\n'),
             throwsArgumentError);
         expect(
             () => SourceSpanWithContext(start2, end2, 'abc', '--abc--abc--\n'),
             throwsArgumentError);
       });
     });

     group('for union()', () {
       test('source URLs must match', () {
         final other = SourceSpan(SourceLocation(12, sourceUrl: 'bar.dart'),
             SourceLocation(13, sourceUrl: 'bar.dart'), '_');

         expect(() => span.union(other), throwsArgumentError);
       });

       test('spans may not be disjoint', () {
         final other = SourceSpan(SourceLocation(13, sourceUrl: 'foo.dart'),
             SourceLocation(14, sourceUrl: 'foo.dart'), '_');

         expect(() => span.union(other), throwsArgumentError);
       });
     });

     test('for compareTo() source URLs must match', () {
       final other = SourceSpan(SourceLocation(12, sourceUrl: 'bar.dart'),
           SourceLocation(13, sourceUrl: 'bar.dart'), '_');

       expect(() => span.compareTo(other), throwsArgumentError);
     });
   });

   test('fields work correctly', () {
     expect(span.start, equals(SourceLocation(5, sourceUrl: 'foo.dart')));
     expect(span.end, equals(SourceLocation(12, sourceUrl: 'foo.dart')));
     expect(span.sourceUrl, equals(Uri.parse('foo.dart')));
     expect(span.length, equals(7));
   });

   group('union()', () {
     test('works with a preceding adjacent span', () {
       final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
           SourceLocation(5, sourceUrl: 'foo.dart'), 'hey, ');

       final result = span.union(other);
       expect(result.start, equals(other.start));
       expect(result.end, equals(span.end));
       expect(result.text, equals('hey, foo bar'));
     });

     test('works with a preceding overlapping span', () {
       final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
           SourceLocation(8, sourceUrl: 'foo.dart'), 'hey, foo');

       final result = span.union(other);
       expect(result.start, equals(other.start));
       expect(result.end, equals(span.end));
       expect(result.text, equals('hey, foo bar'));
     });

     test('works with a following adjacent span', () {
       final other = SourceSpan(SourceLocation(12, sourceUrl: 'foo.dart'),
           SourceLocation(16, sourceUrl: 'foo.dart'), ' baz');

       final result = span.union(other);
       expect(result.start, equals(span.start));
       expect(result.end, equals(other.end));
       expect(result.text, equals('foo bar baz'));
     });

     test('works with a following overlapping span', () {
       final other = SourceSpan(SourceLocation(9, sourceUrl: 'foo.dart'),
           SourceLocation(16, sourceUrl: 'foo.dart'), 'bar baz');

       final result = span.union(other);
       expect(result.start, equals(span.start));
       expect(result.end, equals(other.end));
       expect(result.text, equals('foo bar baz'));
     });

     test('works with an internal overlapping span', () {
       final other = SourceSpan(SourceLocation(7, sourceUrl: 'foo.dart'),
           SourceLocation(10, sourceUrl: 'foo.dart'), 'o b');

       expect(span.union(other), equals(span));
     });

     test('works with an external overlapping span', () {
       final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
           SourceLocation(16, sourceUrl: 'foo.dart'), 'hey, foo bar baz');

       expect(span.union(other), equals(other));
     });
   });

   group('subspan()', () {
     group('errors', () {
       test('start must be greater than zero', () {
         expect(() => span.subspan(-1), throwsRangeError);
       });

       test('start must be less than or equal to length', () {
         expect(() => span.subspan(span.length + 1), throwsRangeError);
       });

       test('end must be greater than start', () {
         expect(() => span.subspan(2, 1), throwsRangeError);
       });

       test('end must be less than or equal to length', () {
         expect(() => span.subspan(0, span.length + 1), throwsRangeError);
       });
     });

     test('preserves the source URL', () {
       final result = span.subspan(1, 2);
       expect(result.start.sourceUrl, equals(span.sourceUrl));
       expect(result.end.sourceUrl, equals(span.sourceUrl));
     });

     test('preserves the context', () {
       final start = SourceLocation(2);
       final end = SourceLocation(5);
       final span = SourceSpanWithContext(start, end, 'abc', '--abc--');
       expect(span.subspan(1, 2).context, equals('--abc--'));
     });

     group('returns the original span', () {
       test('with an implicit end', () => expect(span.subspan(0), equals(span)));

       test('with an explicit end',
           () => expect(span.subspan(0, span.length), equals(span)));
     });

     group('within a single line', () {
       test('returns a strict substring of the original span', () {
         final result = span.subspan(1, 5);
         expect(result.text, equals('oo b'));
         expect(result.start.offset, equals(6));
         expect(result.start.line, equals(0));
         expect(result.start.column, equals(6));
         expect(result.end.offset, equals(10));
         expect(result.end.line, equals(0));
         expect(result.end.column, equals(10));
       });

       test('an implicit end goes to the end of the original span', () {
         final result = span.subspan(1);
         expect(result.text, equals('oo bar'));
         expect(result.start.offset, equals(6));
         expect(result.start.line, equals(0));
         expect(result.start.column, equals(6));
         expect(result.end.offset, equals(12));
         expect(result.end.line, equals(0));
         expect(result.end.column, equals(12));
       });

       test('can return an empty span', () {
         final result = span.subspan(3, 3);
         expect(result.text, isEmpty);
         expect(result.start.offset, equals(8));
         expect(result.start.line, equals(0));
         expect(result.start.column, equals(8));
         expect(result.end, equals(result.start));
       });
     });

     group('across multiple lines', () {
       setUp(() {
         span = SourceSpan(
             SourceLocation(5, line: 2, column: 0),
             SourceLocation(16, line: 4, column: 3),
             'foo\n'
             'bar\n'
             'baz');
       });

       test('with start and end in the middle of a line', () {
         final result = span.subspan(2, 5);
         expect(result.text, equals('o\nb'));
         expect(result.start.offset, equals(7));
         expect(result.start.line, equals(2));
         expect(result.start.column, equals(2));
         expect(result.end.offset, equals(10));
         expect(result.end.line, equals(3));
         expect(result.end.column, equals(1));
       });

       test('with start at the end of a line', () {
         final result = span.subspan(3, 5);
         expect(result.text, equals('\nb'));
         expect(result.start.offset, equals(8));
         expect(result.start.line, equals(2));
         expect(result.start.column, equals(3));
       });

       test('with start at the beginning of a line', () {
         final result = span.subspan(4, 5);
         expect(result.text, equals('b'));
         expect(result.start.offset, equals(9));
         expect(result.start.line, equals(3));
         expect(result.start.column, equals(0));
       });

       test('with end at the end of a line', () {
         final result = span.subspan(2, 3);
         expect(result.text, equals('o'));
         expect(result.end.offset, equals(8));
         expect(result.end.line, equals(2));
         expect(result.end.column, equals(3));
       });

       test('with end at the beginning of a line', () {
         final result = span.subspan(2, 4);
         expect(result.text, equals('o\n'));
         expect(result.end.offset, equals(9));
         expect(result.end.line, equals(3));
         expect(result.end.column, equals(0));
       });
     });
   });

   group('message()', () {
     test('prints the text being described', () {
       expect(span.message('oh no'), equals("""
 line 1, column 6 of foo.dart: oh no
   ,
 1 | foo bar
   | ^^^^^^^
   '"""));
     });

     test('gracefully handles a missing source URL', () {
       final span = SourceSpan(SourceLocation(5), SourceLocation(12), 'foo bar');

       expect(span.message('oh no'), equalsIgnoringWhitespace("""
 line 1, column 6: oh no
   ,
 1 | foo bar
   | ^^^^^^^
   '"""));
     });

     test('gracefully handles empty text', () {
       final span = SourceSpan(SourceLocation(5), SourceLocation(5), '');

       expect(span.message('oh no'), equals('line 1, column 6: oh no'));
     });

     test("doesn't colorize if color is false", () {
       expect(span.message('oh no', color: false), equals("""
 line 1, column 6 of foo.dart: oh no
   ,
 1 | foo bar
   | ^^^^^^^
   '"""));
     });

     test('colorizes if color is true', () {
       expect(span.message('oh no', color: true), equals("""
 line 1, column 6 of foo.dart: oh no
 ${colors.blue}  ,${colors.none}
 ${colors.blue}1 |${colors.none} ${colors.red}foo bar${colors.none}
 ${colors.blue}  |${colors.none} ${colors.red}^^^^^^^${colors.none}
 ${colors.blue}  '${colors.none}"""));
     });

     test("uses the given color if it's passed", () {
       expect(span.message('oh no', color: colors.yellow), equals("""
 line 1, column 6 of foo.dart: oh no
 ${colors.blue}  ,${colors.none}
 ${colors.blue}1 |${colors.none} ${colors.yellow}foo bar${colors.none}
 ${colors.blue}  |${colors.none} ${colors.yellow}^^^^^^^${colors.none}
 ${colors.blue}  '${colors.none}"""));
     });

     test('with context, underlines the right column', () {
       final spanWithContext = SourceSpanWithContext(
           SourceLocation(5, sourceUrl: 'foo.dart'),
           SourceLocation(12, sourceUrl: 'foo.dart'),
           'foo bar',
           '-----foo bar-----');

       expect(spanWithContext.message('oh no', color: colors.yellow), equals("""
 line 1, column 6 of foo.dart: oh no
 ${colors.blue}  ,${colors.none}
 ${colors.blue}1 |${colors.none} -----${colors.yellow}foo bar${colors.none}-----
 ${colors.blue}  |${colors.none} ${colors.yellow}     ^^^^^^^${colors.none}
 ${colors.blue}  '${colors.none}"""));
     });
   });

   group('compareTo()', () {
     test('sorts by start location first', () {
       final other = SourceSpan(SourceLocation(6, sourceUrl: 'foo.dart'),
           SourceLocation(14, sourceUrl: 'foo.dart'), 'oo bar b');

       expect(span.compareTo(other), lessThan(0));
       expect(other.compareTo(span), greaterThan(0));
     });

     test('sorts by length second', () {
       final other = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
           SourceLocation(14, sourceUrl: 'foo.dart'), 'foo bar b');

       expect(span.compareTo(other), lessThan(0));
       expect(other.compareTo(span), greaterThan(0));
     });

     test('considers equal spans equal', () {
       expect(span.compareTo(span), equals(0));
     });
   });

   group('equality', () {
     test('two spans with the same locations are equal', () {
       final other = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
           SourceLocation(12, sourceUrl: 'foo.dart'), 'foo bar');

       expect(span, equals(other));
     });

     test("a different start isn't equal", () {
       final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
           SourceLocation(12, sourceUrl: 'foo.dart'), 'hey, foo bar');

       expect(span, isNot(equals(other)));
     });

     test("a different end isn't equal", () {
       final other = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
           SourceLocation(16, sourceUrl: 'foo.dart'), 'foo bar baz');

       expect(span, isNot(equals(other)));
     });

     test("a different source URL isn't equal", () {
       final other = SourceSpan(SourceLocation(5, sourceUrl: 'bar.dart'),
           SourceLocation(12, sourceUrl: 'bar.dart'), 'foo bar');

       expect(span, isNot(equals(other)));
     });
   });
 }
	// 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.

	import 'package:source_span/source_span.dart';
	import 'package:source_span/src/colors.dart' as colors;
	import 'package:term_glyph/term_glyph.dart' as glyph;
	import 'package:test/test.dart';

	void main() {
	late bool oldAscii;

	setUpAll(() {
	oldAscii = glyph.ascii;
	glyph.ascii = true;
	});

	tearDownAll(() {
	glyph.ascii = oldAscii;
	});

	late SourceSpan span;
	setUp(() {
	span = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
	SourceLocation(12, sourceUrl: 'foo.dart'), 'foo bar');
	});

	group('errors', () {
	group('for new SourceSpan()', () {
	test('source URLs must match', () {
	final start = SourceLocation(0, sourceUrl: 'foo.dart');
	final end = SourceLocation(1, sourceUrl: 'bar.dart');
	expect(() => SourceSpan(start, end, '_'), throwsArgumentError);
	});

	test('end must come after start', () {
	final start = SourceLocation(1);
	final end = SourceLocation(0);
	expect(() => SourceSpan(start, end, '_'), throwsArgumentError);
	});

	test('text must be the right length', () {
	final start = SourceLocation(0);
	final end = SourceLocation(1);
	expect(() => SourceSpan(start, end, 'abc'), throwsArgumentError);
	});
	});

	group('for new SourceSpanWithContext()', () {
	test('context must contain text', () {
	final start = SourceLocation(2);
	final end = SourceLocation(5);
	expect(() => SourceSpanWithContext(start, end, 'abc', '--axc--'),
	throwsArgumentError);
	});

	test('text starts at start.column in context', () {
	final start = SourceLocation(3);
	final end = SourceLocation(5);
	expect(() => SourceSpanWithContext(start, end, 'abc', '--abc--'),
	throwsArgumentError);
	});

	test('text starts at start.column of line in multi-line context', () {
	final start = SourceLocation(4, line: 55, column: 3);
	final end = SourceLocation(7, line: 55, column: 6);
	expect(() => SourceSpanWithContext(start, end, 'abc', '\n--abc--'),
	throwsArgumentError);
	expect(() => SourceSpanWithContext(start, end, 'abc', '\n----abc--'),
	throwsArgumentError);
	expect(() => SourceSpanWithContext(start, end, 'abc', '\n\n--abc--'),
	throwsArgumentError);

	// However, these are valid:
	SourceSpanWithContext(start, end, 'abc', '\n---abc--');
	SourceSpanWithContext(start, end, 'abc', '\n\n---abc--');
	});

	test('text can occur multiple times in context', () {
	final start1 = SourceLocation(4, line: 55, column: 2);
	final end1 = SourceLocation(7, line: 55, column: 5);
	final start2 = SourceLocation(4, line: 55, column: 8);
	final end2 = SourceLocation(7, line: 55, column: 11);
	SourceSpanWithContext(start1, end1, 'abc', '--abc---abc--\n');
	SourceSpanWithContext(start1, end1, 'abc', '--abc--abc--\n');
	SourceSpanWithContext(start2, end2, 'abc', '--abc---abc--\n');
	SourceSpanWithContext(start2, end2, 'abc', '---abc--abc--\n');
	expect(
	() => SourceSpanWithContext(start1, end1, 'abc', '---abc--abc--\n'),
	throwsArgumentError);
	expect(
	() => SourceSpanWithContext(start2, end2, 'abc', '--abc--abc--\n'),
	throwsArgumentError);
	});
	});

	group('for union()', () {
	test('source URLs must match', () {
	final other = SourceSpan(SourceLocation(12, sourceUrl: 'bar.dart'),
	SourceLocation(13, sourceUrl: 'bar.dart'), '_');

	expect(() => span.union(other), throwsArgumentError);
	});

	test('spans may not be disjoint', () {
	final other = SourceSpan(SourceLocation(13, sourceUrl: 'foo.dart'),
	SourceLocation(14, sourceUrl: 'foo.dart'), '_');

	expect(() => span.union(other), throwsArgumentError);
	});
	});

	test('for compareTo() source URLs must match', () {
	final other = SourceSpan(SourceLocation(12, sourceUrl: 'bar.dart'),
	SourceLocation(13, sourceUrl: 'bar.dart'), '_');

	expect(() => span.compareTo(other), throwsArgumentError);
	});
	});

	test('fields work correctly', () {
	expect(span.start, equals(SourceLocation(5, sourceUrl: 'foo.dart')));
	expect(span.end, equals(SourceLocation(12, sourceUrl: 'foo.dart')));
	expect(span.sourceUrl, equals(Uri.parse('foo.dart')));
	expect(span.length, equals(7));
	});

	group('union()', () {
	test('works with a preceding adjacent span', () {
	final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
	SourceLocation(5, sourceUrl: 'foo.dart'), 'hey, ');

	final result = span.union(other);
	expect(result.start, equals(other.start));
	expect(result.end, equals(span.end));
	expect(result.text, equals('hey, foo bar'));
	});

	test('works with a preceding overlapping span', () {
	final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
	SourceLocation(8, sourceUrl: 'foo.dart'), 'hey, foo');

	final result = span.union(other);
	expect(result.start, equals(other.start));
	expect(result.end, equals(span.end));
	expect(result.text, equals('hey, foo bar'));
	});

	test('works with a following adjacent span', () {
	final other = SourceSpan(SourceLocation(12, sourceUrl: 'foo.dart'),
	SourceLocation(16, sourceUrl: 'foo.dart'), ' baz');

	final result = span.union(other);
	expect(result.start, equals(span.start));
	expect(result.end, equals(other.end));
	expect(result.text, equals('foo bar baz'));
	});

	test('works with a following overlapping span', () {
	final other = SourceSpan(SourceLocation(9, sourceUrl: 'foo.dart'),
	SourceLocation(16, sourceUrl: 'foo.dart'), 'bar baz');

	final result = span.union(other);
	expect(result.start, equals(span.start));
	expect(result.end, equals(other.end));
	expect(result.text, equals('foo bar baz'));
	});

	test('works with an internal overlapping span', () {
	final other = SourceSpan(SourceLocation(7, sourceUrl: 'foo.dart'),
	SourceLocation(10, sourceUrl: 'foo.dart'), 'o b');

	expect(span.union(other), equals(span));
	});

	test('works with an external overlapping span', () {
	final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
	SourceLocation(16, sourceUrl: 'foo.dart'), 'hey, foo bar baz');

	expect(span.union(other), equals(other));
	});
	});

	group('subspan()', () {
	group('errors', () {
	test('start must be greater than zero', () {
	expect(() => span.subspan(-1), throwsRangeError);
	});

	test('start must be less than or equal to length', () {
	expect(() => span.subspan(span.length + 1), throwsRangeError);
	});

	test('end must be greater than start', () {
	expect(() => span.subspan(2, 1), throwsRangeError);
	});

	test('end must be less than or equal to length', () {
	expect(() => span.subspan(0, span.length + 1), throwsRangeError);
	});
	});

	test('preserves the source URL', () {
	final result = span.subspan(1, 2);
	expect(result.start.sourceUrl, equals(span.sourceUrl));
	expect(result.end.sourceUrl, equals(span.sourceUrl));
	});

	test('preserves the context', () {
	final start = SourceLocation(2);
	final end = SourceLocation(5);
	final span = SourceSpanWithContext(start, end, 'abc', '--abc--');
	expect(span.subspan(1, 2).context, equals('--abc--'));
	});

	group('returns the original span', () {
	test('with an implicit end', () => expect(span.subspan(0), equals(span)));

	test('with an explicit end',
	() => expect(span.subspan(0, span.length), equals(span)));
	});

	group('within a single line', () {
	test('returns a strict substring of the original span', () {
	final result = span.subspan(1, 5);
	expect(result.text, equals('oo b'));
	expect(result.start.offset, equals(6));
	expect(result.start.line, equals(0));
	expect(result.start.column, equals(6));
	expect(result.end.offset, equals(10));
	expect(result.end.line, equals(0));
	expect(result.end.column, equals(10));
	});

	test('an implicit end goes to the end of the original span', () {
	final result = span.subspan(1);
	expect(result.text, equals('oo bar'));
	expect(result.start.offset, equals(6));
	expect(result.start.line, equals(0));
	expect(result.start.column, equals(6));
	expect(result.end.offset, equals(12));
	expect(result.end.line, equals(0));
	expect(result.end.column, equals(12));
	});

	test('can return an empty span', () {
	final result = span.subspan(3, 3);
	expect(result.text, isEmpty);
	expect(result.start.offset, equals(8));
	expect(result.start.line, equals(0));
	expect(result.start.column, equals(8));
	expect(result.end, equals(result.start));
	});
	});

	group('across multiple lines', () {
	setUp(() {
	span = SourceSpan(
	SourceLocation(5, line: 2, column: 0),
	SourceLocation(16, line: 4, column: 3),
	'foo\n'
	'bar\n'
	'baz');
	});

	test('with start and end in the middle of a line', () {
	final result = span.subspan(2, 5);
	expect(result.text, equals('o\nb'));
	expect(result.start.offset, equals(7));
	expect(result.start.line, equals(2));
	expect(result.start.column, equals(2));
	expect(result.end.offset, equals(10));
	expect(result.end.line, equals(3));
	expect(result.end.column, equals(1));
	});

	test('with start at the end of a line', () {
	final result = span.subspan(3, 5);
	expect(result.text, equals('\nb'));
	expect(result.start.offset, equals(8));
	expect(result.start.line, equals(2));
	expect(result.start.column, equals(3));
	});

	test('with start at the beginning of a line', () {
	final result = span.subspan(4, 5);
	expect(result.text, equals('b'));
	expect(result.start.offset, equals(9));
	expect(result.start.line, equals(3));
	expect(result.start.column, equals(0));
	});

	test('with end at the end of a line', () {
	final result = span.subspan(2, 3);
	expect(result.text, equals('o'));
	expect(result.end.offset, equals(8));
	expect(result.end.line, equals(2));
	expect(result.end.column, equals(3));
	});

	test('with end at the beginning of a line', () {
	final result = span.subspan(2, 4);
	expect(result.text, equals('o\n'));
	expect(result.end.offset, equals(9));
	expect(result.end.line, equals(3));
	expect(result.end.column, equals(0));
	});
	});
	});

	group('message()', () {
	test('prints the text being described', () {
	expect(span.message('oh no'), equals("""
	line 1, column 6 of foo.dart: oh no
	,
	1 \| foo bar
	\| ^^^^^^^
	'"""));
	});

	test('gracefully handles a missing source URL', () {
	final span = SourceSpan(SourceLocation(5), SourceLocation(12), 'foo bar');

	expect(span.message('oh no'), equalsIgnoringWhitespace("""
	line 1, column 6: oh no
	,
	1 \| foo bar
	\| ^^^^^^^
	'"""));
	});

	test('gracefully handles empty text', () {
	final span = SourceSpan(SourceLocation(5), SourceLocation(5), '');

	expect(span.message('oh no'), equals('line 1, column 6: oh no'));
	});

	test("doesn't colorize if color is false", () {
	expect(span.message('oh no', color: false), equals("""
	line 1, column 6 of foo.dart: oh no
	,
	1 \| foo bar
	\| ^^^^^^^
	'"""));
	});

	test('colorizes if color is true', () {
	expect(span.message('oh no', color: true), equals("""
	line 1, column 6 of foo.dart: oh no
	${colors.blue} ,${colors.none}
	${colors.blue}1 \|${colors.none} ${colors.red}foo bar${colors.none}
	${colors.blue} \|${colors.none} ${colors.red}^^^^^^^${colors.none}
	${colors.blue} '${colors.none}"""));
	});

	test("uses the given color if it's passed", () {
	expect(span.message('oh no', color: colors.yellow), equals("""
	line 1, column 6 of foo.dart: oh no
	${colors.blue} ,${colors.none}
	${colors.blue}1 \|${colors.none} ${colors.yellow}foo bar${colors.none}
	${colors.blue} \|${colors.none} ${colors.yellow}^^^^^^^${colors.none}
	${colors.blue} '${colors.none}"""));
	});

	test('with context, underlines the right column', () {
	final spanWithContext = SourceSpanWithContext(
	SourceLocation(5, sourceUrl: 'foo.dart'),
	SourceLocation(12, sourceUrl: 'foo.dart'),
	'foo bar',
	'-----foo bar-----');

	expect(spanWithContext.message('oh no', color: colors.yellow), equals("""
	line 1, column 6 of foo.dart: oh no
	${colors.blue} ,${colors.none}
	${colors.blue}1 \|${colors.none} -----${colors.yellow}foo bar${colors.none}-----
	${colors.blue} \|${colors.none} ${colors.yellow} ^^^^^^^${colors.none}
	${colors.blue} '${colors.none}"""));
	});
	});

	group('compareTo()', () {
	test('sorts by start location first', () {
	final other = SourceSpan(SourceLocation(6, sourceUrl: 'foo.dart'),
	SourceLocation(14, sourceUrl: 'foo.dart'), 'oo bar b');

	expect(span.compareTo(other), lessThan(0));
	expect(other.compareTo(span), greaterThan(0));
	});

	test('sorts by length second', () {
	final other = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
	SourceLocation(14, sourceUrl: 'foo.dart'), 'foo bar b');

	expect(span.compareTo(other), lessThan(0));
	expect(other.compareTo(span), greaterThan(0));
	});

	test('considers equal spans equal', () {
	expect(span.compareTo(span), equals(0));
	});
	});

	group('equality', () {
	test('two spans with the same locations are equal', () {
	final other = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
	SourceLocation(12, sourceUrl: 'foo.dart'), 'foo bar');

	expect(span, equals(other));
	});

	test("a different start isn't equal", () {
	final other = SourceSpan(SourceLocation(0, sourceUrl: 'foo.dart'),
	SourceLocation(12, sourceUrl: 'foo.dart'), 'hey, foo bar');

	expect(span, isNot(equals(other)));
	});

	test("a different end isn't equal", () {
	final other = SourceSpan(SourceLocation(5, sourceUrl: 'foo.dart'),
	SourceLocation(16, sourceUrl: 'foo.dart'), 'foo bar baz');

	expect(span, isNot(equals(other)));
	});

	test("a different source URL isn't equal", () {
	final other = SourceSpan(SourceLocation(5, sourceUrl: 'bar.dart'),
	SourceLocation(12, sourceUrl: 'bar.dart'), 'foo bar');

	expect(span, isNot(equals(other)));
	});
	});
	}