Fix getMetaType of PException

Author: msimacek

graalpython/com.oracle.graal.python.test/src/com/oracle/graal/python/test/interop/InteropLibraryTest.java

@@ -174,6 +174,10 @@ public void testException() {
             context.eval("python", "1/0");
         } catch (PolyglotException e) {
             Value exception = e.getGuestObject();
+            assertTrue(exception.isException());
+            Value clazz = exception.getMetaObject();
+            assertTrue(clazz.isMetaObject());
+            assertEquals("ZeroDivisionError", clazz.getMetaSimpleName());
             assertTrue(exception.hasMember("args"));
             Value args = exception.getMember("args");
             assertTrue(args.hasArrayElements());

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/type/PythonBuiltinClass.java

@@ -33,6 +33,7 @@
 import com.oracle.graal.python.builtins.objects.object.PythonObjectLibrary;
 import com.oracle.graal.python.nodes.ErrorMessages;
 import com.oracle.graal.python.nodes.classes.IsSubtypeNode;
+import com.oracle.graal.python.nodes.interop.PForeignToPTypeNode;
 import com.oracle.truffle.api.CompilerAsserts;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.dsl.Cached;
@@ -87,8 +88,9 @@ boolean isMetaObject() {
     @SuppressWarnings("static-method")
     boolean isMetaInstance(Object instance,
                     @CachedLibrary(limit = "3") PythonObjectLibrary plib,
+                    @Cached PForeignToPTypeNode convert,
                     @Cached IsSubtypeNode isSubtype) {
-        return isSubtype.execute(plib.getLazyPythonClass(instance), this);
+        return isSubtype.execute(plib.getLazyPythonClass(convert.executeConvert(instance)), this);
     }
 
     @ExportMessage