Merge pull request #88 from msgpack/fix-67

Fix Unpacker doesn't increment refcnt.

msgpack/_unpacker.pyx

@@ -206,7 +206,8 @@ cdef class Unpacker(object):
     cdef object file_like
     cdef object file_like_read
     cdef Py_ssize_t read_size
-    cdef object object_hook
+    # To maintain refcnt.
+    cdef object object_hook, object_pairs_hook, list_hook
     cdef object encoding, unicode_errors
     cdef size_t max_buffer_size
 
@@ -224,6 +225,10 @@ cdef class Unpacker(object):
         cdef char *cenc=NULL,
         cdef char *cerr=NULL
 
+        self.object_hook = object_hook
+        self.object_pairs_hook = object_pairs_hook
+        self.list_hook = list_hook
+
         self.file_like = file_like
         if file_like:
             self.file_like_read = file_like.read

test/test_unpack.py

@@ -0,0 +1,47 @@
+from io import BytesIO
+import sys
+from msgpack import Unpacker, packb, OutOfData
+from pytest import raises, mark
+
+
+def test_unpack_array_header_from_file():
+    f = BytesIO(packb([1,2,3,4]))
+    unpacker = Unpacker(f)
+    assert unpacker.read_array_header() == 4
+    assert unpacker.unpack() == 1
+    assert unpacker.unpack() == 2
+    assert unpacker.unpack() == 3
+    assert unpacker.unpack() == 4
+    with raises(OutOfData):
+        unpacker.unpack()
+
+
+@mark.skipif(not hasattr(sys, 'getrefcount'),
+             reason='sys.getrefcount() is needed to pass this test')
+def test_unpacker_hook_refcnt():
+    result = []
+
+    def hook(x):
+        result.append(x)
+        return x
+
+    basecnt = sys.getrefcount(hook)
+
+    up = Unpacker(object_hook=hook, list_hook=hook)
+
+    assert sys.getrefcount(hook) >= basecnt + 2
+
+    up.feed(packb([{}]))
+    up.feed(packb([{}]))
+    assert up.unpack() == [{}]
+    assert up.unpack() == [{}]
+    assert result == [{}, [{}], {}, [{}]]
+
+    del up
+
+    assert sys.getrefcount(hook) == basecnt
+
+
+if __name__ == '__main__':
+    test_unpack_array_header_from_file()
+    test_unpacker_hook_refcnt()

test/test_unpack_file.py

@@ -1,19 +0,0 @@
-from io import BytesIO
-from msgpack import Unpacker, packb, OutOfData
-from pytest import raises
-
-
-def test_unpack_array_header_from_file():
-    f = BytesIO(packb([1,2,3,4]))
-    unpacker = Unpacker(f)
-    assert unpacker.read_array_header() == 4
-    assert unpacker.unpack() == 1
-    assert unpacker.unpack() == 2
-    assert unpacker.unpack() == 3
-    assert unpacker.unpack() == 4
-    with raises(OutOfData):
-        unpacker.unpack()
-
-
-if __name__ == '__main__':
-    test_unpack_array_header_from_file()