Make array_safe insert/upsert work with empty rows

Author: bdowning

sql_athame/dataclasses.py

@@ -440,6 +440,7 @@ async def insert_multiple_unnest(
     async def insert_multiple_array_safe(
         cls: Type[T], connection_or_pool: Union[Connection, Pool], rows: Iterable[T]
     ) -> str:
+        last = ""
         for chunk in chunked(rows, 100):
             last = await connection_or_pool.execute(
                 *cls.insert_multiple_array_safe_sql(chunk)
@@ -467,6 +468,7 @@ async def upsert_multiple_unnest(
     async def upsert_multiple_array_safe(
         cls: Type[T], connection_or_pool: Union[Connection, Pool], rows: Iterable[T]
     ) -> str:
+        last = ""
         for chunk in chunked(rows, 100):
             last = await connection_or_pool.execute(
                 *cls.upsert_sql(cls.insert_multiple_array_safe_sql(chunk))

tests/test_asyncpg.py

@@ -55,6 +55,8 @@ class Test(ModelBase, table_name="test", primary_key="id"):
         b: str
 
     await conn.execute(*Test.create_table_sql())
+    await Test.insert_multiple(conn, [])
+    await Test.upsert_multiple(conn, [])
 
     data = [
         Test(1, 1, "foo"),
@@ -106,6 +108,8 @@ class Test(
         b: str
 
     await conn.execute(*Test.create_table_sql())
+    await Test.insert_multiple(conn, [])
+    await Test.upsert_multiple(conn, [])
 
     data = [
         Test(1, [1], "foo"),