Don't throw for unparseable frames.

test/frame_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.
 
 library frame_test;
 
 import 'package:path/path.dart' as path;
 import 'package:stack_trace/stack_trace.dart';
 import 'package:test/test.dart';
 
@@ skipping 53 matching lines @@
 
     test('parses a folded frame correctly', () {
       var frame = new Frame.parseVM('...');
 
       expect(frame.member, equals('...'));
       expect(frame.uri, equals(new Uri()));
       expect(frame.line, isNull);
       expect(frame.column, isNull);
     });
 
-    test('throws a FormatException for malformed frames', () {
-      expect(() => new Frame.parseVM(''), throwsFormatException);
-      expect(() => new Frame.parseVM('#1'), throwsFormatException);
-      expect(() => new Frame.parseVM('#1      Foo'), throwsFormatException);
-      expect(() => new Frame.parseVM('#1      (dart:async/future.dart:10:15)'),
-          throwsFormatException);
-      expect(() => new Frame.parseVM('Foo (dart:async/future.dart:10:15)'),
-          throwsFormatException);
+    test('returns an UnparsedFrame for malformed frames', () {
+      expectIsUnparsed((text) => new Frame.parseV8(text), '');
+      expectIsUnparsed((text) => new Frame.parseV8(text), '#1');
+      expectIsUnparsed((text) => new Frame.parseV8(text), '#1      Foo');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          '#1      (dart:async/future.dart:10:15)');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          'Foo (dart:async/future.dart:10:15)');
     });
   });
 
   group('.parseV8', () {
     test('parses a stack frame correctly', () {
       var frame = new Frame.parseV8("    at VW.call\$0 "
           "(http://pub.dartlang.org/stuff.dart.js:560:28)");
       expect(frame.uri,
           equals(Uri.parse("http://pub.dartlang.org/stuff.dart.js")));
       expect(frame.line, equals(560));
@@ skipping 120 matching lines @@
 
     test('converts "<anonymous>" to "<fn>"', () {
       String parsedMember(String member) =>
           new Frame.parseV8('    at $member (foo:0:0)').member;
 
       expect(parsedMember('Foo.<anonymous>'), equals('Foo.<fn>'));
       expect(parsedMember('<anonymous>.<anonymous>.bar'),
           equals('<fn>.<fn>.bar'));
     });
 
-    test('throws a FormatException for malformed frames', () {
-      expect(() => new Frame.parseV8(''), throwsFormatException);
-      expect(() => new Frame.parseV8('    at'), throwsFormatException);
-      expect(() => new Frame.parseV8('    at Foo'), throwsFormatException);
-      expect(() => new Frame.parseV8('    at Foo (dart:async/future.dart)'),
-          throwsFormatException);
-      expect(() => new Frame.parseV8('    at Foo (dart:async/future.dart:10)'),
-          throwsFormatException);
-      expect(() => new Frame.parseV8('    at (dart:async/future.dart:10:15)'),
-          throwsFormatException);
-      expect(() => new Frame.parseV8('Foo (dart:async/future.dart:10:15)'),
-          throwsFormatException);
-      expect(() => new Frame.parseV8('    at dart:async/future.dart'),
-          throwsFormatException);
-      expect(() => new Frame.parseV8('    at dart:async/future.dart:10'),
-          throwsFormatException);
-      expect(() => new Frame.parseV8('dart:async/future.dart:10:15'),
-          throwsFormatException);
+    test('returns an UnparsedFrame for malformed frames', () {
+      expectIsUnparsed((text) => new Frame.parseV8(text), '');
+      expectIsUnparsed((text) => new Frame.parseV8(text), '    at');
+      expectIsUnparsed((text) => new Frame.parseV8(text), '    at Foo');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          '    at Foo (dart:async/future.dart)');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          '    at (dart:async/future.dart:10:15)');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          'Foo (dart:async/future.dart:10:15)');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          '    at dart:async/future.dart');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          '    at dart:async/future.dart:10');
+      expectIsUnparsed((text) => new Frame.parseV8(text),
+          'dart:async/future.dart:10:15');
     });
   });
 
   group('.parseFirefox/.parseSafari', () {
     test('parses a simple stack frame correctly', () {
       var frame = new Frame.parseFirefox(
           ".VW.call\$0@http://pub.dartlang.org/stuff.dart.js:560");
       expect(frame.uri,
           equals(Uri.parse("http://pub.dartlang.org/stuff.dart.js")));
       expect(frame.line, equals(560));
@@ skipping 119 matching lines @@
       var frame = new Frame.parseFirefox(
           '.convertDartClosureToJS/\$function</<@'
           'http://pub.dartlang.org/stuff.dart.js:560');
       expect(frame.uri,
           equals(Uri.parse("http://pub.dartlang.org/stuff.dart.js")));
       expect(frame.line, equals(560));
       expect(frame.column, isNull);
       expect(frame.member, equals("convertDartClosureToJS.<fn>.<fn>"));
     });
 
-    test('throws a FormatException for malformed frames', () {
-      expect(() => new Frame.parseFirefox(''), throwsFormatException);
-      expect(() => new Frame.parseFirefox('.foo'), throwsFormatException);
-      expect(() => new Frame.parseFirefox('.foo@dart:async/future.dart'),
-          throwsFormatException);
-      expect(() => new Frame.parseFirefox('.foo(@dart:async/future.dart:10'),
-          throwsFormatException);
-      expect(() => new Frame.parseFirefox('@dart:async/future.dart'),
-          throwsFormatException);
+    test('returns an UnparsedFrame for malformed frames', () {
+      expectIsUnparsed((text) => new Frame.parseFirefox(text), '');
+      expectIsUnparsed((text) => new Frame.parseFirefox(text), '.foo');
+      expectIsUnparsed((text) => new Frame.parseFirefox(text),
+          '.foo@dart:async/future.dart');
+      expectIsUnparsed((text) => new Frame.parseFirefox(text),
+          '.foo(@dart:async/future.dart:10');
+      expectIsUnparsed((text) => new Frame.parseFirefox(text),
+          '@dart:async/future.dart');
     });
 
     test('parses a simple stack frame correctly', () {
       var frame = new Frame.parseFirefox(
           "foo\$bar@http://dartlang.org/foo/bar.dart:10:11");
       expect(frame.uri, equals(Uri.parse("http://dartlang.org/foo/bar.dart")));
       expect(frame.line, equals(10));
       expect(frame.column, equals(11));
       expect(frame.member, equals('foo\$bar'));
     });
@@ skipping 65 matching lines @@
 
     test('parses a stack frame with a relative path correctly', () {
       var frame = new Frame.parseFriendly("foo/bar.dart 10:11    Foo.<fn>.bar");
       expect(frame.uri, equals(
           path.toUri(path.absolute(path.join('foo', 'bar.dart')))));
       expect(frame.line, equals(10));
       expect(frame.column, equals(11));
       expect(frame.member, equals('Foo.<fn>.bar'));
     });
 
-    test('throws a FormatException for malformed frames', () {
-      expect(() => new Frame.parseFriendly(''), throwsFormatException);
-      expect(() => new Frame.parseFriendly('foo/bar.dart'),
-          throwsFormatException);
-      expect(() => new Frame.parseFriendly('foo/bar.dart 10:11'),
-          throwsFormatException);
+    test('returns an UnparsedFrame for malformed frames', () {
+      expectIsUnparsed((text) => new Frame.parseFriendly(text), '');
+      expectIsUnparsed((text) => new Frame.parseFriendly(text), 'foo/bar.dart');
+      expectIsUnparsed((text) => new Frame.parseFriendly(text),
+          'foo/bar.dart 10:11');
     });
   });
 
   test('only considers dart URIs to be core', () {
     bool isCore(String library) =>
       new Frame.parseVM('#0 Foo ($library:0:0)').isCore;
 
     expect(isCore('dart:core'), isTrue);
     expect(isCore('dart:async'), isTrue);
     expect(isCore('dart:core/uri.dart'), isTrue);
@@ skipping 66 matching lines @@
           equals('dart:core/uri.dart 5 in Foo'));
     });
 
     test('prints relative paths as relative', () {
       var relative = path.normalize('relative/path/to/foo.dart');
       expect(new Frame.parseFriendly('$relative 5:10  Foo').toString(),
           equals('$relative 5:10 in Foo'));
     });
   });
 }
+
+void expectIsUnparsed(Frame constructor(String text), String text) {
+  var frame = constructor(text);
+  expect(frame, new isInstanceOf<UnparsedFrame>());
+  expect(frame.toString(), equals(text));
+}