BUG20301989: Fix conversion of empty set

peeyushgupta · peeyushgupta · commit f9b22fa1c3fa · 2015-03-12T12:06:41.000+05:30
We fix conversion of SET data coming from MySQL server
when the set is empty. We now return an empty set(set([])) which
was previously returned as a set of empty string(set([''])).

A test case is added for BUG#20301989.
diff --git a/lib/mysql/connector/conversion.py b/lib/mysql/connector/conversion.py
@@ -1,5 +1,5 @@
 # MySQL Connector/Python - MySQL driver written in Python.
-# Copyright (c) 2009, 2014, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved.
 
 # MySQL Connector/Python is licensed under the terms of the GPLv2
 # <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most
@@ -539,6 +539,8 @@ def _SET_to_python(self, value, dsc=None):  # pylint: disable=C0103
         """
         set_type = None
         val = value.decode(self.charset)
+        if not val:
+            return set()
         try:
             set_type = set(val.split(','))
         except ValueError:
diff --git a/src/mysql_capi.c b/src/mysql_capi.c
@@ -1,6 +1,6 @@
 /*
 # MySQL Connector/Python - MySQL driver written in Python.
-# Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.
 
 # MySQL Connector/Python is licensed under the terms of the GPLv2
 # <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most
@@ -2308,9 +2308,15 @@ MySQL_fetch_row(MySQL *self)
             {
                 if (field_flags & SET_FLAG)
                 {
-                    value= PySet_New(PyUnicode_Split(value,
-                                                     PyStringFromString(","),
-                                                     -1));
+                    if (!strlen(row[i]))
+                    {
+                        value= PySet_New(NULL);
+                    }
+                    else
+                    {
+                        value= PySet_New(PyUnicode_Split(
+                                         value, PyStringFromString(","), -1));
+                    }
                     if (!value)
                     {
                         goto error;
diff --git a/tests/test_bugs.py b/tests/test_bugs.py
@@ -3336,3 +3336,48 @@ def test_binary_charset(self):
 
         self.cur.execute("SELECT * FROM {0}".format(self.tbl))
         self.assertEqual(exp, self.cur.fetchall())
+
+
+class BugOra20301989(tests.MySQLConnectorTests):
+    """BUG#20301989: SET DATA TYPE NOT TRANSLATED CORRECTLY WHEN EMPTY
+    """
+    def setUp(self):
+        config = tests.get_mysql_config()
+        cnx = connection.MySQLConnection(**config)
+        cur = cnx.cursor()
+
+        self.tbl = 'Bug20301989'
+        cur.execute("DROP TABLE IF EXISTS {0}".format(self.tbl))
+
+        create = ("CREATE TABLE {0} (col1 SET('val1', 'val2')) "
+                  "DEFAULT CHARSET latin1".format(self.tbl))
+        cur.execute(create)
+        cur.close()
+        cnx.close()
+
+    def tearDown(self):
+        config = tests.get_mysql_config()
+        cnx = connection.MySQLConnection(**config)
+        cur = cnx.cursor()
+        cur.execute("DROP TABLE IF EXISTS {0}".format(self.tbl))
+        cur.close()
+        cnx.close()
+
+    @foreach_cnx()
+    def test_set(self):
+        cur = self.cnx.cursor()
+        sql = "INSERT INTO {0} VALUES(%s)".format(self.tbl)
+        cur.execute(sql, ('val1,val2',))
+        cur.execute(sql, ('val1',))
+        cur.execute(sql, ('',))
+        cur.execute(sql, (None,))
+
+        exp = [
+            (set([u'val1', u'val2']),),
+            (set([u'val1']),),
+            (set([]),),
+            (None,)
+        ]
+
+        cur.execute("SELECT * FROM {0}".format(self.tbl))
+        self.assertEqual(exp, cur.fetchall())
