add sync tx tests

tests/table/test_tx.py

@@ -0,0 +1,91 @@
+import pytest
+from contextlib import suppress
+
+import ydb.iam
+
+
+def test_tx_commit(driver_sync, database):
+    session = driver_sync.table_client.session().create()
+    prepared = session.prepare(
+        "DECLARE $param as Int32;\n SELECT $param as value",
+    )
+
+    tx = session.transaction()
+    tx.execute(prepared, {"$param": 2})
+    tx.commit()
+    tx.commit()
+
+
+def test_tx_rollback(driver_sync, database):
+    session = driver_sync.table_client.session().create()
+    prepared = session.prepare(
+        "DECLARE $param as Int32;\n SELECT $param as value",
+    )
+
+    tx = session.transaction()
+    tx.execute(prepared, {"$param": 2})
+    tx.rollback()
+    tx.rollback()
+
+
+def test_tx_begin(driver_sync, database):
+    session = driver_sync.table_client.session().create()
+    session.create()
+
+    tx = session.transaction()
+    tx.begin()
+    tx.begin()
+    tx.rollback()
+
+
+def test_credentials():
+    credentials = ydb.iam.MetadataUrlCredentials()
+    raised = False
+    try:
+        credentials.auth_metadata()
+    except Exception:
+        raised = True
+
+    assert raised
+
+
+def test_tx_snapshot_ro(driver_sync, database):
+    session = driver_sync.table_client.session().create()
+    description = (
+        ydb.TableDescription()
+        .with_primary_keys("key")
+        .with_columns(
+            ydb.Column("key", ydb.OptionalType(ydb.PrimitiveType.Uint64)),
+            ydb.Column("value", ydb.OptionalType(ydb.PrimitiveType.Uint64)),
+        )
+    )
+    tb_name = f"{database}/test"
+    with suppress(ydb.issues.SchemeError):
+        session.drop_table(tb_name)
+    session.create_table(tb_name, description)
+    session.transaction(ydb.SerializableReadWrite()).execute(
+        """INSERT INTO `test` (`key`, `value`) VALUES (1, 1), (2, 2)""",
+        commit_tx=True,
+    )
+
+    ro_tx = session.transaction(tx_mode=ydb.SnapshotReadOnly())
+    data1 = ro_tx.execute("SELECT value FROM `test` WHERE key = 1")
+
+    session.transaction(ydb.SerializableReadWrite()).execute(
+        "UPDATE `test` SET value = value + 1", commit_tx=True
+    )
+
+    data2 = ro_tx.execute("SELECT value FROM `test` WHERE key = 1")
+    assert data1[0].rows == data2[0].rows == [{"value": 1}]
+
+    ro_tx.commit()
+
+    with pytest.raises(ydb.issues.GenericError) as exc_info:
+        ro_tx.execute("UPDATE `test` SET value = value + 1")
+    assert "read only transaction" in exc_info.value.message
+
+    data = session.transaction(tx_mode=ydb.SnapshotReadOnly()).execute(
+        "SELECT value FROM `test` WHERE key = 1",
+        commit_tx=True,
+    )
+    assert data[0].rows == [{"value": 2}]