fix sscursor

Author: jettify

tornado_mysql/connections.py

@@ -1022,7 +1022,7 @@ def init_unbuffered_query(self):
             self.connection = None
         else:
             self.field_count = first_packet.read_length_encoded_integer()
-            self._get_descriptions()
+            yield self._get_descriptions()
 
             # Apparently, MySQLdb picks this number because it's the maximum
             # value of a 64bit unsigned integer. Since we're emulating MySQLdb,

tornado_mysql/cursors.py

@@ -393,7 +393,7 @@ def fetchone(self):
         self._check_executed()
         row = yield self.read_next()
         if row is None:
-            raise gen.Return()
+            raise gen.Return(None)
         self.rownumber += 1
         raise gen.Return(row)
 
@@ -427,6 +427,7 @@ def fetchmany(self, size=None):
             self.rownumber += 1
         raise gen.Return(rows)
 
+    @gen.coroutine
     def scroll(self, value, mode='relative'):
         self._check_executed()
 
@@ -436,7 +437,7 @@ def scroll(self, value, mode='relative'):
                         "Backwards scrolling not supported by this cursor")
 
             for _ in range_type(value):
-                self.read_next()
+                yield self.read_next()
             self.rownumber += value
         elif mode == 'absolute':
             if value < self.rownumber:
@@ -445,7 +446,7 @@ def scroll(self, value, mode='relative'):
 
             end = value - self.rownumber
             for _ in range_type(end):
-                self.read_next()
+                yield self.read_next()
             self.rownumber = value
         else:
             raise ProgrammingError("unknown scroll mode %s" % mode)