Raise exception by default in expression_to_value (#60)

* Raise exception by default in expression_to_value

* add a comment

* fix

* comments

* fix format

* limit mysql-connector-python<9.0.0

* fix mysql-connector

* add a comment

mysql_mimic/intercept.py

@@ -3,6 +3,8 @@
 from typing import Any
 
 from sqlglot import expressions as exp
+
+from mysql_mimic.errors import MysqlError, ErrorCode
 from mysql_mimic.variables import DEFAULT
 
 
@@ -60,4 +62,7 @@ def expression_to_value(expression: exp.Expression) -> Any:
         return True
     if expression.name == "OFF":
         return False
-    return expression.name
+    raise MysqlError(
+        "Complex expressions in variables not supported yet",
+        code=ErrorCode.NOT_SUPPORTED_YET,
+    )

tests/conftest.py

@@ -208,6 +208,9 @@ async def mysql_connector_conn(
     connect: ConnectFixture,
 ) -> AsyncGenerator[MySQLConnectionAbstract, None]:
     conn = await connect(user="levon_helm")
+    # Different versions of mysql-connector use various default collations.
+    # Execute the following query to ensure consistent test results across different versions.
+    await query(conn, "SET NAMES 'utf8mb4' COLLATE 'utf8mb4_general_ci'")
     try:
         yield conn
     finally:

tests/test_query.py

@@ -370,12 +370,12 @@ async def test_query_attributes(
         ),
         (
             """
-            SELECT 
-              /*+ SET_VAR(max_execution_time=2) */ 
-              x 
+            SELECT
+              /*+ SET_VAR(max_execution_time=2) */
+              x
             FROM (
-              SELECT 
-                /*+ SET_VAR(max_execution_time=1) */ 
+              SELECT
+                /*+ SET_VAR(max_execution_time=1) */
                 @@max_execution_time AS x
             ) AS a
             """,
@@ -839,6 +839,11 @@ async def test_commands(
         ),
         ("SET @foo = 'bar'", "User-defined variables not supported yet"),
         ("KILL 'abc'", "Invalid KILL connection ID"),
+        (
+            # pick a dynamic string session var
+            "SET init_connect='abc' in xyz",
+            "Complex expressions in variables not supported yet",
+        ),
     ],
 )
 async def test_unsupported_commands(