fix: required columns on newly created tables retain migration safety checks

tests/unit/test_sql_analyser.py

@@ -221,6 +221,34 @@ class SqliteAnalyserTestCase(SqlAnalyserTestCase):
 class PostgresqlAnalyserTestCase(SqlAnalyserTestCase):
     database_vendor = "postgresql"
 
+    def test_add_required_foreign_key_to_new_table(self):
+        sql = [
+            'CREATE TABLE "archive_capture" ("id" uuid NOT NULL PRIMARY KEY);',
+            'ALTER TABLE "archive_capture" ADD COLUMN "source_id" uuid NOT NULL REFERENCES "archive_source" ("id") DEFERRABLE INITIALLY DEFERRED;',
+        ]
+        self.assertValidSql(sql)
+
+    def test_add_required_foreign_key_to_existing_table(self):
+        sql = [
+            'CREATE TABLE "archive_capture" ("id" uuid NOT NULL PRIMARY KEY);',
+            'ALTER TABLE "other_app_capture" ADD COLUMN "source_id" uuid NOT NULL REFERENCES "archive_source" ("id") DEFERRABLE INITIALLY DEFERRED;',
+        ]
+        self.assertBackwardIncompatibleSql(sql, "NOT_NULL")
+
+    def test_add_required_foreign_key_after_conditional_create(self):
+        sql = [
+            'CREATE TABLE IF NOT EXISTS "legacy" ("id" uuid NOT NULL PRIMARY KEY);',
+            'ALTER TABLE "legacy" ADD COLUMN "source_id" uuid NOT NULL REFERENCES "archive_source" ("id") DEFERRABLE INITIALLY DEFERRED;',
+        ]
+        self.assertBackwardIncompatibleSql(sql, "NOT_NULL")
+
+    def test_add_required_foreign_key_to_new_qualified_table(self):
+        sql = [
+            'CREATE TABLE "archive"."capture" ("id" uuid NOT NULL PRIMARY KEY);',
+            'ALTER TABLE "archive"."capture" ADD COLUMN "source_id" uuid NOT NULL REFERENCES "archive"."source" ("id") DEFERRABLE INITIALLY DEFERRED;',
+        ]
+        self.assertValidSql(sql)
+
     def test_alter_column(self):
         sql = 'ALTER TABLE "app_alter_column_a" ALTER COLUMN "field" TYPE varchar(10) USING "field"::varchar(10);'
         self.assertBackwardIncompatibleSql(sql)