drop-and-recreate defaults on enum modification (#125)

migra/changes.py

@@ -130,18 +130,29 @@ def get_enum_modifications(tables_from, tables_target, enums_from, enums_target)
     recreate = Statements()
     post = Statements()
     enums_to_change = e_modified
+
     for t, v in t_modified.items():
         t_before = tables_from[t]
         _, _, c_modified, _ = differences(t_before.columns, v.columns)
         for k, c in c_modified.items():
             before = t_before.columns[k]
+
             if (
                 c.is_enum == before.is_enum
                 and c.dbtypestr == before.dbtypestr
                 and c.enum != before.enum
             ):
+                has_default = c.default and not c.is_generated
+
+                if has_default:
+                    pre.append(before.drop_default_statement(t))
+
                 pre.append(before.change_enum_to_string_statement(t))
                 post.append(before.change_string_to_enum_statement(t))
+
+                if has_default:
+                    post.append(before.add_default_statement(t))
+
     for e in enums_to_change.values():
         recreate.append(e.drop_statement)
         recreate.append(e.create_statement)

pyproject.toml

@@ -14,7 +14,7 @@ python = "*"
 sqlbag = "*"
 six = "*"
 # schemainspect = {path="../schemainspect"}
-schemainspect = ">=0.1.1585871494"
+schemainspect = ">=0.1.1586428725"
 psycopg2-binary = { version="*", optional = true }
 
 [tool.poetry.dev-dependencies]

tests/FIXTURES/enumdefaults/a.sql

@@ -0,0 +1,6 @@
+create type order_status as enum('pending', 'processing', 'complete');
+
+create table orders(
+  id serial primary key,
+  status order_status default 'pending'::order_status
+);

tests/FIXTURES/enumdefaults/b.sql

@@ -0,0 +1,6 @@
+create type order_status as enum('pending', 'processing', 'complete', 'rejected');
+
+create table orders(
+  id serial primary key,
+  status order_status default 'pending'::order_status
+)

tests/FIXTURES/enumdefaults/expected.sql

@@ -0,0 +1,11 @@
+alter table "public"."orders" alter column "status" drop default;
+
+alter table "public"."orders" alter column "status" set data type varchar using "status"::varchar;
+
+drop type "public"."order_status";
+
+create type "public"."order_status" as enum ('pending', 'processing', 'complete', 'rejected');
+
+alter table "public"."orders" alter column "status" set data type order_status using "status"::order_status;
+
+alter table "public"."orders" alter column "status" set default 'pending'::order_status;

tests/test_migra.py

@@ -84,6 +84,11 @@ def test_privs():
         do_fixture_test(FIXTURE_NAME, with_privileges=True)
 
 
+def test_enumdefaults():
+    for FIXTURE_NAME in ["enumdefaults"]:
+        do_fixture_test(FIXTURE_NAME, with_privileges=True)
+
+
 schemainspect_test_role = "schemainspect_test_role"