commit fix for noticing wrapped exception types

pythonnet/src/runtime/converter.cs

@@ -225,6 +225,12 @@ namespace Python.Runtime {
 			mt = ManagedType.GetManagedObject(value);
 		    }
 		}
+		IntPtr c = Exceptions.UnwrapExceptionClass(value);
+		if ((c != IntPtr.Zero) && (c != value)) {
+		    value = c;
+		    Runtime.Decref(c);
+		    mt = ManagedType.GetManagedObject(value);
+		}
 	    }
 	    }
 

pythonnet/src/runtime/exceptions.cs

@@ -192,6 +192,23 @@ namespace Python.Runtime {
 	    return op;
 	}
 
+	internal static IntPtr UnwrapExceptionClass(IntPtr op) {
+	    // In some cases its necessary to recognize an exception *class*,
+	    // and obtain the inner (wrapped) exception class. This method
+	    // returns the inner class if found, or a null pointer.
+
+	    IntPtr d = Runtime.PyObject_GetAttrString(op, "__dict__");
+	    if (d == IntPtr.Zero) {
+		Exceptions.Clear();
+		return IntPtr.Zero;
+	    }
+	    IntPtr c = Runtime.PyDict_GetItemString(d, "_class");
+	    Runtime.Decref(d);
+	    if (c == IntPtr.Zero) {
+		Exceptions.Clear();
+	    }
+	    return c;
+	}
 
 
 	/// <summary>

pythonnet/src/runtime/managedtype.cs

@@ -47,18 +47,17 @@ namespace Python.Runtime {
 		    return (ManagedType)gc.Target;
 		}
 
+		// In certain situations, we need to recognize a wrapped
+		// exception class and be willing to unwrap the class :(
 
-//  		// Hmm - check to see if its a wrapped exception?
-//  		if (Runtime.wrap_exceptions) {
-//  		    IntPtr p = Runtime.PyObject_GetAttrString(ob, "_inner");
-//  		    if (p != IntPtr.Zero) {
-//  			ManagedType m = GetManagedObject(p);
-//  			Runtime.Decref(p);
-//  			if (m != null)
-//  			    return m;
-//  		    }
-//  		}
-
+		if (Runtime.wrap_exceptions) {
+		    IntPtr e = Exceptions.UnwrapExceptionClass(ob);
+		    if ((e != IntPtr.Zero) && (e != ob)) {
+			ManagedType m = GetManagedObject(e);
+			Runtime.Decref(e);
+			return m;
+		    }
+		}
 	    }
 	    return null;
 	}