pkg/stack_trace: fix vm_test

test/vm_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.
 
 /// This file tests stack_trace's ability to parse live stack traces. It's a
 /// dual of dartium_test.dart, since method names can differ somewhat from
 /// platform to platform. No similar file exists for dart2js since the specific
 /// method names there are implementation details.
 @TestOn('vm')
 
 import 'package:path/path.dart' as path;
 import 'package:stack_trace/stack_trace.dart';
 import 'package:test/test.dart';
 
+// The name of this (trivial) function is verified as part of the test
+String getStackTraceString() => StackTrace.current.toString();
+
+// The name of this (trivial) function is verified as part of the test
+StackTrace getStackTraceObject() => StackTrace.current;
+
 Frame getCaller([int level]) {
   if (level == null) return new Frame.caller();
   return new Frame.caller(level);
 }
 
 Frame nestedGetCaller(int level) => getCaller(level);
 
 Trace getCurrentTrace([int level]) => new Trace.current(level);
 
 Trace nestedGetCurrentTrace(int level) => getCurrentTrace(level);
 
 void main() {
   group('Trace', () {
     test('.parse parses a real stack trace correctly', () {
-      var string = StackTrace.current.toString();
+      var string = getStackTraceString();
       var trace = new Trace.parse(string);
       expect(path.url.basename(trace.frames.first.uri.path),
           equals('vm_test.dart'));
       expect(trace.frames.first.member, equals('getStackTraceString'));
     });
 
     test('converts from a native stack trace correctly', () {
-      var trace = new Trace.from(StackTrace.current);
+      var trace = new Trace.from(getStackTraceObject());
       expect(path.url.basename(trace.frames.first.uri.path),
           equals('vm_test.dart'));
       expect(trace.frames.first.member, equals('getStackTraceObject'));
     });
 
     test('.from handles a stack overflow trace correctly', () {
       overflow() => overflow();
 
       var trace;
       try {
@@ skipping 48 matching lines @@
 
     test('at level 2 returns the grandparent frame', () {
       expect(nestedGetCaller(2).member, equals('main.<fn>.<fn>'));
     });
 
     test('throws an ArgumentError for negative levels', () {
       expect(() => new Frame.caller(-1), throwsArgumentError);
     });
   });
 }