object: factor wrap_object out of lookup_object_prefix.

Generating an `Object *` from a `git_object *` may be useful in other
functions (e.g. the upcoming `Repository_revparse_single`).

include/pygit2/object.h

@@ -37,5 +37,6 @@ PyObject* Object_get_oid(Object *self);
 PyObject* Object_get_hex(Object *self);
 PyObject* Object_get_type(Object *self);
 PyObject* Object_read_raw(Object *self);
+PyObject* wrap_object(git_object *c_object, Repository *repo);
 
 #endif

src/pygit2/object.c

@@ -34,6 +34,12 @@
 #include <pygit2/repository.h>
 #include <pygit2/object.h>
 
+extern PyTypeObject TreeType;
+extern PyTypeObject CommitType;
+extern PyTypeObject BlobType;
+extern PyTypeObject TagType;
+
+
 void
 Object_dealloc(Object* self)
 {
@@ -145,3 +151,35 @@ PyTypeObject ObjectType = {
     0,                                         /* tp_alloc          */
     0,                                         /* tp_new            */
 };
+
+PyObject *
+wrap_object(git_object *c_object, Repository *repo)
+{
+    Object *py_obj = NULL;
+
+    switch (git_object_type(c_object)) {
+        case GIT_OBJ_COMMIT:
+            py_obj = PyObject_New(Object, &CommitType);
+            break;
+        case GIT_OBJ_TREE:
+            py_obj = PyObject_New(Object, &TreeType);
+            break;
+        case GIT_OBJ_BLOB:
+            py_obj = PyObject_New(Object, &BlobType);
+            break;
+        case GIT_OBJ_TAG:
+            py_obj = PyObject_New(Object, &TagType);
+            break;
+        default:
+            assert(0);
+    }
+
+    if (py_obj) {
+        py_obj->obj = c_object;
+				if (repo) {
+            py_obj->repo = repo;
+            Py_INCREF(repo);
+        }
+    }
+    return (PyObject *)py_obj;
+}

src/pygit2/repository.c

@@ -31,6 +31,7 @@
 #include <pygit2/types.h>
 #include <pygit2/reference.h>
 #include <pygit2/utils.h>
+#include <pygit2/object.h>
 #include <pygit2/oid.h>
 #include <pygit2/repository.h>
 
@@ -40,9 +41,6 @@ extern PyTypeObject IndexType;
 extern PyTypeObject WalkerType;
 extern PyTypeObject SignatureType;
 extern PyTypeObject TreeType;
-extern PyTypeObject CommitType;
-extern PyTypeObject BlobType;
-extern PyTypeObject TagType;
 extern PyTypeObject TreeBuilderType;
 extern PyTypeObject ConfigType;
 extern PyTypeObject DiffType;
@@ -72,29 +70,7 @@ lookup_object_prefix(Repository *repo, const git_oid *oid, size_t len,
     if (err < 0)
         return Error_set_oid(err, oid, len);
 
-    switch (git_object_type(obj)) {
-        case GIT_OBJ_COMMIT:
-            py_obj = PyObject_New(Object, &CommitType);
-            break;
-        case GIT_OBJ_TREE:
-            py_obj = PyObject_New(Object, &TreeType);
-            break;
-        case GIT_OBJ_BLOB:
-            py_obj = PyObject_New(Object, &BlobType);
-            break;
-        case GIT_OBJ_TAG:
-            py_obj = PyObject_New(Object, &TagType);
-            break;
-        default:
-            assert(0);
-    }
-
-    if (py_obj) {
-        py_obj->obj = obj;
-        py_obj->repo = repo;
-        Py_INCREF(repo);
-    }
-    return (PyObject*)py_obj;
+    return wrap_object(obj, repo);
 }
 
 PyObject *