Fix transform() dropping AUTOINCREMENT from INTEGER PRIMARY KEY columns

sqlite_utils/db.py

@@ -1400,6 +1400,7 @@ def create_table_sql(
         extracts: Optional[Union[Dict[str, str], List[str]]] = None,
         if_not_exists: bool = False,
         strict: bool = False,
+        autoincrement: bool = False,
     ) -> str:
         """
         Returns the SQL ``CREATE TABLE`` statement for creating the specified table.
@@ -1496,6 +1497,8 @@ def sort_key(p):
             column_extras = []
             if column_name == single_pk:
                 column_extras.append("PRIMARY KEY")
+                if autoincrement:
+                    column_extras.append("AUTOINCREMENT")
             if column_name in not_null:
                 column_extras.append("NOT NULL")
             if column_name in defaults and defaults[column_name] is not None:
@@ -2807,6 +2810,8 @@ def fk_with_renamed_columns(fk: ForeignKey) -> ForeignKey:
         if column_order is not None:
             column_order = [rename.get(col) or col for col in column_order]
 
+        has_autoincrement = "autoincrement" in self.schema.lower()
+
         sqls = []
         sqls.append(
             self.db.create_table_sql(
@@ -2818,6 +2823,7 @@ def fk_with_renamed_columns(fk: ForeignKey) -> ForeignKey:
                 foreign_keys=create_table_foreign_keys,
                 column_order=column_order,
                 strict=self.strict if strict is None else strict,
+                autoincrement=has_autoincrement,
             ).strip()
         )
 

tests/test_transform.py

@@ -758,6 +758,25 @@ def test_transform_with_indexes_errors(fresh_db, transform_params):
     )
 
 
+def test_transform_preserves_autoincrement(fresh_db):
+    fresh_db.execute(
+        "CREATE TABLE t (id INTEGER PRIMARY KEY AUTOINCREMENT, val TEXT)"
+    )
+    fresh_db["t"].insert({"val": "one"})
+    fresh_db["t"].insert({"val": "two"})
+    fresh_db["t"].transform(rename={"val": "value"})
+    assert "AUTOINCREMENT" in fresh_db["t"].schema
+    # Confirm the column is still the primary key
+    assert fresh_db["t"].pks == ["id"]
+
+
+def test_transform_without_autoincrement_not_affected(fresh_db):
+    fresh_db.execute("CREATE TABLE t (id INTEGER PRIMARY KEY, val TEXT)")
+    fresh_db["t"].insert({"val": "one"})
+    fresh_db["t"].transform(rename={"val": "value"})
+    assert "AUTOINCREMENT" not in fresh_db["t"].schema
+
+
 def test_transform_with_unique_constraint_implicit_index(fresh_db):
     dogs = fresh_db["dogs"]
     # Create a table with a UNIQUE constraint on 'name', which creates an implicit index