BUG#36570707: Collation set on connect using C-Extension is ignored

SubCoder1 · SubCoder1 · commit 9f12cb673c82 · 2024-05-23T18:24:01.000+05:30
This patch fixes the issue where the collation passed through the
connection option was getting ignored and default collation was
being set by C API.

Change-Id: Idacbd07fadfdc7a754140b7104db6172f1bc2f52
diff --git a/CHANGES.txt b/CHANGES.txt
@@ -15,6 +15,7 @@ v9.0.0
 - WL#16318: Deprecate Cursors Prepared Raw and Named Tuple
 - WL#16283: Remove OpenTelemetry Bundled Installation
 - BUG#36611371: Update dnspython required versions to allow latest 2.6.1
+- BUG#36570707: Collation set on connect using C-Extension is ignored
 - BUG#36476195: Incorrect escaping in pure Python mode if sql_mode includes NO_BACKSLASH_ESCAPES
 - BUG#36289767: MySQLCursorBufferedRaw does not skip conversion
 
diff --git a/mysql-connector-python/lib/mysql/connector/abstracts.py b/mysql-connector-python/lib/mysql/connector/abstracts.py
@@ -1269,13 +1269,6 @@ def set_charset_collation(
 
         self._execute_query(f"SET NAMES '{charset_name}' COLLATE '{collation_name}'")
 
-        try:
-            # Required for C Extension
-            self.set_character_set_name(charset_name)
-        except AttributeError:
-            # Not required for pure Python connection
-            pass
-
         if self.converter:
             self.converter.set_charset(charset_name, character_set=self._character_set)
 
diff --git a/mysql-connector-python/tests/cext/test_cext_connection.py b/mysql-connector-python/tests/cext/test_cext_connection.py
@@ -197,11 +197,9 @@ def test_connection_id(self):
     def test_cursor(self):
         """Test CEXT cursors."""
 
-        class FalseCursor:
-            ...
+        class FalseCursor: ...
 
-        class TrueCursor(cursor_cext.CMySQLCursor):
-            ...
+        class TrueCursor(cursor_cext.CMySQLCursor): ...
 
         self.assertRaises(
             errors.ProgrammingError, self.cnx.cursor, cursor_class=FalseCursor
@@ -285,6 +283,9 @@ def test_character_set(self):
                 self.assertTupleEqual(("ascii", "ascii_general_ci"), res)
 
         for charset_id, charset, collation in [
+            (303, "utf8mb4", "utf8mb4_ja_0900_as_cs"),
+            (46, "utf8mb4", "utf8mb4_bin"),
+            (45, "utf8mb4", "utf8mb4_general_ci"),
             (26, "cp1250", "cp1250_general_ci"),
             (8, "latin1", "latin1_swedish_ci"),
         ]:
@@ -296,6 +297,11 @@ def test_character_set(self):
                     cur.execute("SELECT @@character_set_client, @@collation_connection")
                     res = cur.fetchone()
                     self.assertTupleEqual((config["charset"], config["collation"]), res)
+                cnx.cmd_change_user(config["user"], config["password"], config["database"], charset=charset_id)
+                with cnx.cursor() as cur:
+                    cur.execute("SELECT @@character_set_client, @@collation_connection")
+                    res = cur.fetchone()
+                    self.assertTupleEqual((config["charset"], config["collation"]), res)
 
         config["client_flags"] = (
             ClientFlag.get_default() | ClientFlag.CAN_HANDLE_EXPIRED_PASSWORDS
