From 0637b9d71bdbf793410c02e607b3a0dcf97c2810 Mon Sep 17 00:00:00 2001
From: Markus Ewald <cygon@nuclex.org>
Date: Thu, 8 Mar 2012 17:14:42 +0000
Subject: [PATCH] Moved another helper method that tests whether a type is
 carrying an attribute into the TypeHelper class

git-svn-id: file:///srv/devel/repo-conversion/nusu@271 d2e56fa2-650e-0410-a79f-9358c0239efd
---
 Source/Plugins/NoPluginAttribute.Test.cs |  4 ++--
 Source/Plugins/PluginHost.cs             | 17 +----------------
 Source/TypeHelper.Test.cs                | 17 +++++++++++++++++
 Source/TypeHelper.cs                     | 11 +++++++++++
 4 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/Source/Plugins/NoPluginAttribute.Test.cs b/Source/Plugins/NoPluginAttribute.Test.cs
index 0fef369..0a51fda 100644
--- a/Source/Plugins/NoPluginAttribute.Test.cs
+++ b/Source/Plugins/NoPluginAttribute.Test.cs
@@ -35,8 +35,8 @@ namespace Nuclex.Support.Plugins {
     ///   Tests whether the default consturctor of the no plugin attribute works
     /// </summary>
     [Test]
-    public void TestDefaultConstructor() {
-      new NoPluginAttribute();
+    public void HasDefaultConstructor() {
+      Assert.NotNull(new NoPluginAttribute());
     }
 
   }
diff --git a/Source/Plugins/PluginHost.cs b/Source/Plugins/PluginHost.cs
index e0287d5..0344d07 100644
--- a/Source/Plugins/PluginHost.cs
+++ b/Source/Plugins/PluginHost.cs
@@ -86,8 +86,7 @@ namespace Nuclex.Support.Plugins {
         }
 
         // Types that have been tagged with the [NoPlugin] attribute will be ignored
-        object[] attributes = type.GetCustomAttributes(true);
-        if(containsNoPluginAttribute(attributes)) {
+        if(type.HasAttribute<NoPluginAttribute>()) {
           continue;
         }
 
@@ -104,20 +103,6 @@ namespace Nuclex.Support.Plugins {
 
     }
 
-    /// <summary>
-    ///   Determines whether the specifies list of attributes contains a NoPluginAttribute
-    /// </summary>
-    /// <param name="attributes">List of attributes to check</param>
-    /// <returns>True if the list contained a NoPluginAttribute, false otherwise</returns>
-    private static bool containsNoPluginAttribute(object[] attributes) {
-      for(int index = 0; index < attributes.Length; ++index) {
-        if(attributes[index] is NoPluginAttribute) {
-          return true;
-        }
-      }
-      return false;
-    }
-
     /// <summary>Reports an error to the debugging console</summary>
     /// <param name="error">Error message that will be reported</param>
     private static void reportError(string error) {
diff --git a/Source/TypeHelper.Test.cs b/Source/TypeHelper.Test.cs
index 050a9a8..b993784 100644
--- a/Source/TypeHelper.Test.cs
+++ b/Source/TypeHelper.Test.cs
@@ -86,6 +86,23 @@ namespace Nuclex.Support {
 
     #endregion // class Derived
 
+    #region class HasIgnoreAttribute
+
+    /// <summary>Class that carries an IgnoreAttribute</summary>
+    [Ignore]
+    private class HasIgnoreAttribute { }
+
+    #endregion // class HasIgnoreAttribute
+
+    /// <summary>
+    ///   Verifies that the type helper can determine whether a class is carrying an attribute
+    /// </summary>
+    [Test]
+    public void CanDetermineIfTypeHasAttribute() {
+      Assert.IsTrue(typeof(HasIgnoreAttribute).HasAttribute<IgnoreAttribute>());
+      Assert.IsFalse(typeof(HasIgnoreAttribute).HasAttribute<TestAttribute>());
+    }
+
     /// <summary>
     ///   Verifies that the GetFieldInfosIncludingBaseClasses() will include the backing
     ///   fields of automatically implemented properties in base classes
diff --git a/Source/TypeHelper.cs b/Source/TypeHelper.cs
index 0ceee0f..6592f73 100644
--- a/Source/TypeHelper.cs
+++ b/Source/TypeHelper.cs
@@ -167,6 +167,17 @@ namespace Nuclex.Support {
       return false;
     }
 
+    /// <summary>Determines whether the type has the specified attribute</summary>
+    /// <typeparam name="TAttribute">Attribute the type will be checked for</typeparam>
+    /// <param name="type">
+    ///   Type that will be checked for presence of the specified attribute
+    /// </param>
+    /// <returns>True if the type has the specified attribute, otherwise false</returns>
+    public static bool HasAttribute<TAttribute>(this Type type) {
+      object[] attributes = type.GetCustomAttributes(typeof(TAttribute), true);
+      return (attributes != null) && (attributes.Length > 0);
+    }
+
   }
 
 } // namespace Nuclex.Support