Optimize successive calls SourceFile.getLine().

test/utils_test.dart

 // 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.
 
 import 'package:test/test.dart';
 import 'package:source_span/src/utils.dart';
 
 main() {
-  group('binary search', () {
-    test('empty', () {
-      expect(binarySearch([], (x) => true), -1);
-    });
-
-    test('single element', () {
-      expect(binarySearch([1], (x) => true), 0);
-      expect(binarySearch([1], (x) => false), 1);
-    });
-
-    test('no matches', () {
-      var list = [1, 2, 3, 4, 5, 6, 7];
-      expect(binarySearch(list, (x) => false), list.length);
-    });
-
-    test('all match', () {
-      var list = [1, 2, 3, 4, 5, 6, 7];
-      expect(binarySearch(list, (x) => true), 0);
-    });
-
-    test('compare with linear search', () {
-      for (int size = 0; size < 100; size++) {
-        var list = [];
-        for (int i = 0; i < size; i++) {
-          list.add(i);
-        }
-        for (int pos = 0; pos <= size; pos++) {
-          expect(binarySearch(list, (x) => x >= pos),
-              _linearSearch(list, (x) => x >= pos));
-        }
-      }
-    });
-  });
-
   group('find line start', () {
     test('skip entries in wrong column', () {
       var context = '0_bb\n1_bbb\n2b____\n3bbb\n';
       var index = findLineStart(context, 'b', 1);
       expect(index, 11);
       expect(context.substring(index - 1, index + 3), '\n2b_');
     });
 
     test('end of line column for empty text', () {
       var context = '0123\n56789\nabcdefgh\n';
@@ skipping 27 matching lines @@
   });
 }
 
 _linearSearch(list, predicate) {
   if (list.length == 0) return -1;
   for (int i = 0; i < list.length; i++) {
     if (predicate(list[i])) return i;
   }
   return list.length;
 }