improve fasta interpolation recovery

pkg/analyzer/test/generated/scanner_test.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 analyzer.test.generated.scanner_test;
 
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/dart/scanner/reader.dart';
 import 'package:analyzer/src/dart/scanner/scanner.dart';
@@ skipping 61 matching lines @@
     CharSequenceReader baseReader = new CharSequenceReader("xyzzy");
     CharacterRangeReader reader = new CharacterRangeReader(baseReader, 1, 4);
     reader.offset = 2;
     expect(reader.offset, 2);
   }
 }
 
 @reflectiveTest
 class LineInfoTest extends EngineTestCase {
   void test_lineInfo_multilineComment() {
-    String source = "/*\r *\r */";
+    String source = "/*\r\n *\r\n */";

[ahe, 2017/05/31 13:15:48]

Perhaps Fasta should support \r line endings?

[danrubel, 2017/06/01 19:02:46]

I don't think we need to do so given that most (all?) OS EOL is denoted by LF or
CR-LF. I'd rather not add more code to the scanner unless we need to support
this situation.

     _assertLineInfo(source, [
       new ScannerTest_ExpectedLocation(0, 1, 1),
-      new ScannerTest_ExpectedLocation(4, 2, 2),
+      new ScannerTest_ExpectedLocation(5, 2, 2),
       new ScannerTest_ExpectedLocation(source.length - 1, 3, 3)
     ]);
   }
 
   void test_lineInfo_multilineString() {
     String source = "'''a\r\nbc\r\nd'''";
     _assertLineInfo(source, [
       new ScannerTest_ExpectedLocation(0, 1, 1),
       new ScannerTest_ExpectedLocation(7, 2, 2),
       new ScannerTest_ExpectedLocation(source.length - 1, 3, 4)
@@ skipping 131 matching lines @@
     buffer.write(token.type);
     buffer.write(", '");
     buffer.write(token.lexeme);
     buffer.write("', ");
     buffer.write(token.offset);
     buffer.write(", ");
     buffer.write(token.length);
     buffer.write("]");
   }
 }