PostgreSQL: Support OPERATOR members in ALTER EXTENSION

fuzz/fuzz_seeds/postgres_alter_extension.sql

@@ -31,3 +31,4 @@ ALTER EXTENSION citext DROP PROCEDURE public.p(int);
 ALTER EXTENSION citext ADD ROUTINE public.r(int);
 ALTER EXTENSION citext DROP AGGREGATE agg(int ORDER BY text);
 ALTER EXTENSION citext ADD AGGREGATE cnt(*);
+ALTER EXTENSION citext ADD OPERATOR - (NONE, int);

src/ast/ddl.rs

@@ -4961,6 +4961,8 @@ pub enum AlterExtensionMember {
     },
     /// `MATERIALIZED VIEW object_name`
     MaterializedView(ObjectName),
+    /// `OPERATOR operator_name (left_type, right_type)`
+    Operator(DropOperatorSignature),
     /// `PROCEDURE procedure_name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ]`
     Procedure(FunctionDesc),
     /// `PUBLICATION object_name`
@@ -5038,6 +5040,7 @@ impl fmt::Display for AlterExtensionMember {
                 }
             }
             AlterExtensionMember::MaterializedView(name) => write!(f, "MATERIALIZED VIEW {name}"),
+            AlterExtensionMember::Operator(signature) => write!(f, "OPERATOR {signature}"),
             AlterExtensionMember::Procedure(function) => write!(f, "PROCEDURE {function}"),
             AlterExtensionMember::Publication(name) => write!(f, "PUBLICATION {name}"),
             AlterExtensionMember::Routine(function) => write!(f, "ROUTINE {function}"),

src/parser/mod.rs

@@ -9131,8 +9131,8 @@ impl<'a> Parser<'a> {
         }))
     }
 
-    /// Parse an operator signature for a [Statement::DropOperator]
-    /// Format: `name ( { left_type | NONE } , right_type )`
+    /// Parse an operator signature in the form
+    /// `name ( { left_type | NONE } , right_type )`
     fn parse_drop_operator_signature(&mut self) -> Result<DropOperatorSignature, ParserError> {
         let name = self.parse_operator_name()?;
         self.expect_token(&Token::LParen)?;
@@ -12576,6 +12576,10 @@ impl<'a> Parser<'a> {
             Ok(AlterExtensionMember::MaterializedView(
                 self.parse_object_name(false)?,
             ))
+        } else if self.parse_keyword(Keyword::OPERATOR) {
+            Ok(AlterExtensionMember::Operator(
+                self.parse_drop_operator_signature()?,
+            ))
         } else if self.parse_keyword(Keyword::PROCEDURE) {
             Ok(AlterExtensionMember::Procedure(self.parse_function_desc()?))
         } else if self.parse_keyword(Keyword::PUBLICATION) {

tests/sqlparser_postgres.rs

@@ -13558,6 +13558,8 @@ fn alter_extension_member_round_trip_forms(action: &str) {
         format!("ALTER EXTENSION ext_name {action} LANGUAGE plpgsql"),
         format!("ALTER EXTENSION ext_name {action} PROCEDURAL LANGUAGE plpgsql"),
         format!("ALTER EXTENSION ext_name {action} MATERIALIZED VIEW mv"),
+        format!("ALTER EXTENSION ext_name {action} OPERATOR + (INT, TEXT)"),
+        format!("ALTER EXTENSION ext_name {action} OPERATOR - (NONE, INT)"),
         format!("ALTER EXTENSION ext_name {action} PROCEDURE p"),
         format!("ALTER EXTENSION ext_name {action} PROCEDURE p()"),
         format!("ALTER EXTENSION ext_name {action} PROCEDURE p(INT)"),
@@ -13762,6 +13764,18 @@ fn parse_alter_extension_add_member() {
         other => panic!("unexpected statement: {other:?}"),
     }
 
+    match pg_and_generic().verified_stmt("ALTER EXTENSION ext_name ADD OPERATOR - (NONE, INT)") {
+        Statement::AlterExtension(AlterExtension {
+            operation: AlterExtensionOperation::Add(AlterExtensionMember::Operator(signature)),
+            ..
+        }) => {
+            assert_eq!(signature.name, ObjectName::from(Ident::new("-")));
+            assert_eq!(signature.left_type, None);
+            assert_eq!(signature.right_type, DataType::Int(None));
+        }
+        other => panic!("unexpected statement: {other:?}"),
+    }
+
     for (sql, error) in [
         (
             "ALTER EXTENSION ext_name ADD",
@@ -13791,6 +13805,10 @@ fn parse_alter_extension_add_member() {
             "ALTER EXTENSION ext_name ADD ROUTINE 1",
             "Expected: identifier, found: 1",
         ),
+        (
+            "ALTER EXTENSION ext_name ADD OPERATOR +",
+            "Expected: (, found: EOF",
+        ),
     ] {
         assert_eq!(
             pg_and_generic().parse_sql_statements(sql).unwrap_err(),