Fixed copy() on DictRow

Close #1073.

NEWS

@@ -10,6 +10,7 @@ What's new in psycopg 2.8.5
   `~psycopg2.extras.LoggingConnection` (:ticket:`#1026`).
 - `~psycopg2.extensions.Column` objects in `cursor.description` can be sliced
   (:ticket:`#1034`).
+- Fixed `~copy.copy()` of `~psycopg2.extras.DictCursor` rows (:ticket:`#1073`).
 
 
 What's new in psycopg 2.8.4

lib/extras.py

@@ -196,6 +196,10 @@ class DictRow(list):
     def __contains__(self, x):
         return x in self._index
 
+    def __reduce__(self):
+        # this is apparently useless, but it fixes #1073
+        return super(DictRow, self).__reduce__()
+
     def __getstate__(self):
         return self[:], self._index.copy()
 
@@ -392,6 +396,7 @@ class NamedTupleCursor(_cursor):
 def _cached_make_nt(cls, key):
     return cls._do_make_nt(key)
 
+
 # Exposed for testability, and if someone wants to monkeypatch to tweak
 # the cache size.
 NamedTupleCursor._cached_make_nt = classmethod(_cached_make_nt)
@@ -410,7 +415,8 @@ class LoggingConnection(_connection):
         instance from the standard logging module.
         """
         self._logobj = logobj
-        if _logging and isinstance(logobj, (_logging.Logger, _logging.LoggerAdapter)):
+        if _logging and isinstance(
+                logobj, (_logging.Logger, _logging.LoggerAdapter)):
             self.log = self._logtologger
         else:
             self.log = self._logtofile

tests/test_extras_dictcursor.py

@@ -15,6 +15,7 @@
 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 # License for more details.
 
+import copy
 import time
 import pickle
 import unittest
@@ -158,6 +159,20 @@ class ExtrasDictCursorTests(_DictCursorBase):
         self.assertEqual(r['b'], r1['b'])
         self.assertEqual(r._index, r1._index)
 
+    def test_copy(self):
+        curs = self.conn.cursor(cursor_factory=psycopg2.extras.DictCursor)
+        curs.execute("select 10 as foo, 'hi' as bar")
+        rv = curs.fetchone()
+        self.assertEqual(len(rv), 2)
+
+        rv2 = copy.copy(rv)
+        self.assertEqual(len(rv2), 2)
+        self.assertEqual(len(rv), 2)
+
+        rv3 = copy.deepcopy(rv)
+        self.assertEqual(len(rv3), 2)
+        self.assertEqual(len(rv), 2)
+
     @skip_from_python(3)
     def test_iter_methods_2(self):
         curs = self.conn.cursor(cursor_factory=psycopg2.extras.DictCursor)
@@ -267,6 +282,20 @@ class ExtrasDictCursorRealTests(_DictCursorBase):
         self.assertEqual(r['a'], r1['a'])
         self.assertEqual(r['b'], r1['b'])
 
+    def test_copy(self):
+        curs = self.conn.cursor(cursor_factory=psycopg2.extras.RealDictCursor)
+        curs.execute("select 10 as foo, 'hi' as bar")
+        rv = curs.fetchone()
+        self.assertEqual(len(rv), 2)
+
+        rv2 = copy.copy(rv)
+        self.assertEqual(len(rv2), 2)
+        self.assertEqual(len(rv), 2)
+
+        rv3 = copy.deepcopy(rv)
+        self.assertEqual(len(rv3), 2)
+        self.assertEqual(len(rv), 2)
+
     def testDictCursorRealWithNamedCursorFetchOne(self):
         self._testWithNamedCursorReal(lambda curs: curs.fetchone())