Catch.Only with throwingAction, closes #205

machine · Jan 23, 2014 · c2e17a3 · c2e17a3
1 parent 1ad146c
commit c2e17a3
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Showing 2 changed files with 57 additions and 4 deletions.
diff --git a/Source/Machine.Specifications.Specs/CatchSpecs.cs b/Source/Machine.Specifications.Specs/CatchSpecs.cs
@@ -81,4 +81,51 @@ public class with_a_non_throwing_Func
         () => Result.Should().BeNull();
     }
   }
+
+  [Subject(typeof(Catch))]
+  public class when_calling_Catch_Only_with_an_Action
+  {
+    [Subject(typeof(Catch))]
+    public class with_a_throwing_Action_which_matches_exception_to_be_caught
+    {
+      static ArgumentException AnException;
+      static Exception Result;
+
+      Establish context = () => { AnException = new ArgumentException(); };
+
+      Because of = () => { Result = Catch.Only<ArgumentException>(() => { throw AnException; }); };
+
+      It should_return_the_same_exception =
+        () => Result.Should().BeSameAs(AnException);
+    }
+
+    [Subject(typeof(Catch))]
+    public class with_a_throwing_Action_which_doesnt_match_exception_to_be_caught
+    {
+      static ArgumentException AnException;
+      static Exception Result;
+
+      Establish context = () => { AnException = new ArgumentException(); };
+
+      Because of = () => { Result = Catch.Exception(() => Catch.Only<InvalidOperationException>(() => { throw AnException; })); };
+
+      It should_return_the_same_exception =
+        () => Result.Should().BeSameAs(AnException);
+    }
+
+    [Subject(typeof(Catch))]
+    public class with_a_non_throwing_Action
+    {
+      static string ActionSideEffect;
+      static Exception Result;
+
+      Because of = () => { Result = Catch.Only<ArgumentException>((() => { ActionSideEffect = "hi"; })); };
+
+      It should_access_the_propety =
+        () => ActionSideEffect.Should().Be("hi");
+
+      It should_return_null =
+        () => Result.Should().BeNull();
+    }
+  }
 }
diff --git a/Source/Machine.Specifications/Catch.cs b/Source/Machine.Specifications/Catch.cs
@@ -5,10 +5,15 @@ namespace Machine.Specifications
   public static class Catch
   {
     public static Exception Exception(Action throwingAction)
+    {
+      return Only<Exception>(throwingAction);
+    }
+
+    public static Exception Exception<T>(Func<T> throwingFunc)
     {
       try
       {
-        throwingAction();
+        throwingFunc();
       }
       catch (Exception exception)
       {
@@ -18,13 +23,14 @@ public static Exception Exception(Action throwingAction)
       return null;
     }
 
-    public static Exception Exception<T>(Func<T> throwingFunc)
+    public static TException Only<TException>(Action throwingAction)
+      where TException : Exception
     {
       try
       {
-        throwingFunc();
+        throwingAction();
       }
-      catch (Exception exception)
+      catch (TException exception)
       {
         return exception;
       }