Python builtin hashfunc closure fix

If the wrong return type in the hash function was used, an error:
  SystemError: error return without exception set
was raised

Add some tests for testing builtin slots

Examples/test-suite/python/Makefile.in

@@ -58,6 +58,7 @@ CPP_TEST_CASES += \
 	primitive_types \
 	python_abstractbase \
 	python_append \
+	python_builtin \
 	python_destructor_exception \
 	python_director \
 	python_docstring \

Examples/test-suite/python/python_builtin_runme.py

@@ -0,0 +1,26 @@
+from python_builtin import *
+
+if is_python_builtin():
+  # Test 1 for tp_hash
+  if hash(SimpleValue(222)) != 222:
+    raise RuntimeError("tp_hash not working")
+
+  # Test 2 for tp_hash
+  try:
+    # Was incorrectly raising: SystemError: error return without exception set
+    h = hash(BadHashFunctionReturnType())
+    raise RuntimeError("Missing TypeError")
+  except TypeError:
+    pass
+
+  # Test 3 for tp_hash
+  passed = False
+  try:
+    h = hash(ExceptionHashFunction())
+  except RuntimeError, e:
+    passed = str(e).find("oops") != -1
+    pass
+
+  if not passed:
+    raise RuntimeError("did not catch exception in hash()")
+

Examples/test-suite/python_builtin.i

@@ -0,0 +1,74 @@
+// Test customizing slots when using the -builtin option
+
+%module python_builtin
+
+%inline %{
+#ifdef SWIGPYTHON_BUILTIN
+bool is_python_builtin() { return true; }
+#else
+bool is_python_builtin() { return false; }
+#endif
+%}
+
+// Test 1 for tp_hash
+#if defined(SWIGPYTHON_BUILTIN)
+%feature("python:tp_hash") SimpleValue "SimpleValueHashFunction"
+#endif
+
+%inline %{
+struct SimpleValue {
+  int value;
+  SimpleValue(int value) : value(value) {}
+  static SimpleValue *inout(SimpleValue *sv) {
+    return sv;
+  }
+};
+%}
+
+%{
+#if PY_VERSION_HEX >= 0x03020000
+Py_hash_t SimpleValueHashFunction(PyObject *v)
+#else
+long SimpleValueHashFunction(PyObject *v)
+#endif
+{
+  SwigPyObject *sobj = (SwigPyObject *) v;
+  SimpleValue *p = (SimpleValue *)sobj->ptr;
+  return p->value;
+}
+hashfunc test_hashfunc_cast() {
+    return SimpleValueHashFunction;
+}
+%}
+
+// Test 2 for tp_hash
+#if defined(SWIGPYTHON_BUILTIN)
+%feature("python:slot", "tp_hash", functype="hashfunc") BadHashFunctionReturnType::bad_hash_function;
+#endif
+
+%inline %{
+struct BadHashFunctionReturnType {
+    static const char * bad_hash_function() {
+      return "bad hash function";
+    }
+};
+%}
+
+// Test 3 for tp_hash
+#if defined(SWIGPYTHON_BUILTIN)
+%feature("python:slot", "tp_hash", functype="hashfunc") ExceptionHashFunction::exception_hash_function;
+#endif
+
+%catches(const char *) exception_hash_function;
+
+%inline %{
+#if PY_VERSION_HEX < 0x03020000
+  #define Py_hash_t long
+#endif
+struct ExceptionHashFunction {
+    static Py_hash_t exception_hash_function() {
+      throw "oops";
+    }
+};
+%}
+

Lib/python/builtin.swg

@@ -192,9 +192,11 @@ wrapper##_closure(PyObject *a) {		\
     PyObject *pyresult;				\
     long result;				\
     pyresult = wrapper(a, NULL);		\
-    if (!pyresult || !PyLong_Check(pyresult))	\
-	return -1;				\
+    if (!pyresult)				\
+      return -1;				\
     result = PyLong_AsLong(pyresult);		\
+    if (PyErr_Occurred())			\
+      result = -1;				\
     Py_DECREF(pyresult);			\
     return result;				\
 }