Reference: deprecate get_object() in favour of peel()

Let Reference.peel()'s argument be optional, and default to GIT_OBJ_ANY,
which mirrors the behaviour of get_object().

Since we reimplement the get_object() behaviour, change it to call
peel() which makes sure we can keep using the old tests for this aspect.

src/reference.c

@@ -367,36 +367,35 @@ Reference_log(Reference *self)
 PyDoc_STRVAR(Reference_get_object__doc__,
   "get_object() -> object\n"
   "\n"
-  "Retrieves the object the current reference is pointing to.");
+  "Retrieves the object the current reference is pointing to.\n"
+  "\n"
+  "This method is deprecated, please use Reference.peel() instead.");
 
 PyObject *
 Reference_get_object(Reference *self)
 {
-    int err;
+    return PyObject_CallMethod((PyObject *) self, "peel", NULL);
-    git_object* obj;
-
-    CHECK_REFERENCE(self);
-
-    err = git_reference_peel(&obj, self->reference, GIT_OBJ_ANY);
-    if (err < 0)
-        return Error_set(err);
-
-    return wrap_object(obj, self->repo);
 }
 
 PyDoc_STRVAR(Reference_peel__doc__,
-  "peel(type) -> object\n"
+  "peel(type=None) -> object\n"
   "\n"
-  "Retrieve an object of the given type by recursive peeling.");
+  "Retrieve an object of the given type by recursive peeling.\n"
+  "\n"
+  "If no type is provided, the first non-tag object will be returned.");
 
 PyObject *
-Reference_peel(Reference *self, PyObject *py_type)
+Reference_peel(Reference *self, PyObject *args)
 {
     int err, type;
     git_object *obj;
+    PyObject *py_type = Py_None;
 
     CHECK_REFERENCE(self);
 
+    if (!PyArg_ParseTuple(args, "|O", &py_type))
+        return NULL;
+
     type = py_object_to_object_type(py_type);
     if (type == -1)
         return NULL;
@@ -502,7 +501,7 @@ PyMethodDef Reference_methods[] = {
     METHOD(Reference, log, METH_NOARGS),
     METHOD(Reference, get_object, METH_NOARGS),
     METHOD(Reference, set_target, METH_VARARGS | METH_KEYWORDS),
-    METHOD(Reference, peel, METH_O),
+    METHOD(Reference, peel, METH_VARARGS),
     {NULL}
 };
 

src/utils.c

@@ -181,6 +181,9 @@ py_object_to_object_type(PyObject *py_type)
 {
     int type = -1;
 
+    if (py_type == Py_None)
+        return GIT_OBJ_ANY;
+
     if (PyLong_Check(py_type)) {
         type = PyLong_AsLong(py_type);
         if (type == -1 && PyErr_Occurred())