anchor.diff:  library analyzer.test.reflective_tests;
   
   import 'dart:async';
  -@MirrorsUsed(metaTargets: 'ReflectiveTest')
   import 'dart:mirrors';
   
   import 'package:unittest/unittest.dart';
  +
  +/**
  + * A marker annotation used to annotate overridden test methods (so we cannot
  + * rename them to `fail_`) which are expected to fail at `assert` in the
  + * checked mode.
  + */
  +const _AssertFailingTest assertFailingTest = const _AssertFailingTest();
   
   /**
    * A marker annotation used to annotate overridden test methods (so we cannot
  
positive.code:   });
  }
  
  bool _hasFailingTestAnnotation(MethodMirror method) {
    return method.metadata.any((InstanceMirror annotation) =>
        annotation.type.reflectedType == _FailingTest);
  }
  
  Future _invokeSymbolIfExists(InstanceMirror instanceMirror, Symbol symbol) {
    var invocationResult = null;
  
negative.code:  * for the annotated classes.
   */
  const ReflectiveTest reflectiveTest = const ReflectiveTest();
  
  /**
   * Is `true` the application is running in the checked mode.
   */
  final bool _isCheckedMode = () {
    try {
      assert(false);
      return false;
    } catch (_) {
      return true;
    }
  }();
  
  /**
   * Runs test methods existing in the given [type].
  