/// <summary>
        /// Apply tag filtering.
        /// </summary>
        /// <param name="classes">List of test classes.</param>
        /// <param name="instances">Test class instance dictionary.</param>
        protected override void FilterCustomTestClasses(IList <ITestClass> classes, TestClassInstanceDictionary instances)
        {
            if (string.IsNullOrEmpty(TagExpression))
            {
                return;
            }

            // Temporarily apply to the methods as well. If the class has no
            // methods that were matched in the expression, then cut the
            // class from the run.
            List <ITestClass> emptyTests = new List <ITestClass>();

            foreach (ITestClass test in classes)
            {
                object instance = instances.GetInstance(test.Type);
                ICollection <ITestMethod> methods = GetTestMethods(test, instance);
                TagManager tm = new TagManager(test.Type, methods);
                ApplyExpression(tm, methods);
                if (methods.Count == 0)
                {
                    emptyTests.Add(test);
                }
            }
            if (emptyTests.Count > 0)
            {
                foreach (ITestClass test in emptyTests)
                {
                    classes.Remove(test);
                }
            }

            if (!_hasLoggedWarning)
            {
                UnitTestHarness.LogWriter.Information(string.Format(CultureInfo.InvariantCulture, Properties.UnitTestMessage.TagTestRunFilter_TaggingInUse, TagExpression));
                _hasLoggedWarning = true;
            }
        }
    /// <summary>
    /// Apply tag filtering.
    /// </summary>
    /// <param name="classes">List of test classes.</param>
    /// <param name="instances">Test class instance dictionary.</param>
    protected override void FilterCustomTestClasses(IList<ITestClass> classes, TestClassInstanceDictionary instances)
    {
      if (string.IsNullOrEmpty(TagExpression))
      {
        return;
      }

      // Temporarily apply to the methods as well. If the class has no 
      // methods that were matched in the expression, then cut the 
      // class from the run.
      List<ITestClass> emptyTests = new List<ITestClass>();
      foreach (ITestClass test in classes)
      {
        object instance = instances.GetInstance(test.Type);
        ICollection<ITestMethod> methods = GetTestMethods(test, instance);
        TagManager tm = new TagManager(test.Type, methods);
        ApplyExpression(tm, methods);
        if (methods.Count == 0)
        {
          emptyTests.Add(test);
        }
      }
      if (emptyTests.Count > 0)
      {
        foreach (ITestClass test in emptyTests)
        {
          classes.Remove(test);
        }
      }

      if (!_hasLoggedWarning)
      {
        UnitTestHarness.LogWriter.Information(string.Format(CultureInfo.InvariantCulture, Properties.UnitTestMessage.TagTestRunFilter_TaggingInUse, TagExpression));
        _hasLoggedWarning = true;
      }
    }
 /// <summary>
 /// Apply the tag filtering.
 /// </summary>
 /// <param name="tagManager">The tag manager instance.</param>
 /// <param name="methods">Set of methods.</param>
 private void ApplyExpression(TagManager tagManager, ICollection<ITestMethod> methods)
 {
   List<ITestMethod> original = new List<ITestMethod>(methods);
   methods.Clear();
   tagManager.EvaluateExpression(TagExpression);
   foreach (ITestMethod method in tagManager.EvaluateExpression(TagExpression))
   {
     if (original.Contains(method))
     {
       methods.Add(method);
     }
   }
 }
    /// <summary>
    /// Apply tag filtering.
    /// </summary>
    /// <param name="methods">List of test methods.</param>
    protected override void FilterCustomTestMethods(IList<ITestMethod> methods)
    {
      if (methods == null || methods.Count == 0 || string.IsNullOrEmpty(TagExpression))
      {
        return;
      }

      TagManager tm = new TagManager(methods[0].Method.ReflectedType, methods);
      ApplyExpression(tm, methods);
    }
 /// <summary>
 /// Evaluate a tag expression.
 /// </summary>
 /// <param name="owner">The owner object.</param>
 /// <param name="tagExpression">Tag expression.</param>
 /// <returns>Test methods associated with the tag expression.</returns>
 public static IEnumerable<ITestMethod> Evaluate(TagManager owner, string tagExpression)
 {
   return new ExpressionEvaluator(owner, tagExpression).Evaluate();
 }
 /// <summary>
 /// Create an expression evaluator.
 /// </summary>
 /// <param name="owner">The owner object.</param>
 /// <param name="tagExpression">Expression object.</param>
 private ExpressionEvaluator(TagManager owner, string tagExpression)
 {
   if (tagExpression == null)
   {
     throw new ArgumentNullException("tagExpression");
   }
   else if (tagExpression.Length == 0)
   {
     throw new ArgumentException(Properties.UnitTestMessage.TagManager_ExpressionEvaluator_EmptyTagExpression, "tagExpression");
   }
   _owner = owner;
   _tagExpression = tagExpression;
 }
 /// <summary>
 /// Evaluate a tag expression.
 /// </summary>
 /// <param name="owner">The owner object.</param>
 /// <param name="tagExpression">Tag expression.</param>
 /// <returns>Test methods associated with the tag expression.</returns>
 public static IEnumerable <ITestMethod> Evaluate(TagManager owner, string tagExpression)
 {
     return(new ExpressionEvaluator(owner, tagExpression).Evaluate());
 }