PostgreSQL: Support TYPE members in ALTER EXTENSION

fuzz/fuzz_seeds/postgres_alter_extension.sql

@@ -36,3 +36,4 @@ ALTER EXTENSION citext DROP OPERATOR CLASS oc USING btree;
 ALTER EXTENSION citext DROP OPERATOR FAMILY of USING btree;
 ALTER EXTENSION citext ADD CAST (int AS text);
 ALTER EXTENSION citext ADD TRANSFORM FOR int LANGUAGE plpgsql;
+ALTER EXTENSION citext DROP TYPE public.ty;

src/ast/ddl.rs

@@ -5021,6 +5021,8 @@ pub enum AlterExtensionMember {
         /// Language name.
         language: Ident,
     },
+    /// `TYPE object_name`
+    Type(DataType),
     /// `VIEW object_name`
     View(ObjectName),
 }
@@ -5104,6 +5106,7 @@ impl fmt::Display for AlterExtensionMember {
                 type_name,
                 language,
             } => write!(f, "TRANSFORM FOR {type_name} LANGUAGE {language}"),
+            AlterExtensionMember::Type(data_type) => write!(f, "TYPE {data_type}"),
             AlterExtensionMember::View(name) => write!(f, "VIEW {name}"),
         }
     }

src/parser/mod.rs

@@ -12652,6 +12652,8 @@ impl<'a> Parser<'a> {
                 type_name,
                 language,
             })
+        } else if self.parse_keyword(Keyword::TYPE) {
+            Ok(AlterExtensionMember::Type(self.parse_data_type()?))
         } else if self.parse_keyword(Keyword::VIEW) {
             Ok(AlterExtensionMember::View(self.parse_object_name(false)?))
         } else {

tests/sqlparser_postgres.rs

@@ -13584,6 +13584,7 @@ fn alter_extension_member_round_trip_forms(action: &str) {
         format!("ALTER EXTENSION ext_name {action} TEXT SEARCH PARSER pgrm"),
         format!("ALTER EXTENSION ext_name {action} TEXT SEARCH TEMPLATE tpl"),
         format!("ALTER EXTENSION ext_name {action} TRANSFORM FOR my_type LANGUAGE plpgsql"),
+        format!("ALTER EXTENSION ext_name {action} TYPE my_type"),
         format!("ALTER EXTENSION ext_name {action} VIEW v"),
     ];
     for sql in sqls {
@@ -13911,6 +13912,10 @@ fn parse_alter_extension_add_member() {
             "ALTER EXTENSION ext_name ADD TRANSFORM FOR my_type LANGUAGE",
             "Expected: identifier, found: EOF",
         ),
+        (
+            "ALTER EXTENSION ext_name ADD TYPE",
+            "Expected: a data type name, found: EOF",
+        ),
     ] {
         assert_eq!(
             pg_and_generic().parse_sql_statements(sql).unwrap_err(),