From 3bddcad85dd3b89deee4c947f3bdb578bd575208 Mon Sep 17 00:00:00 2001
From: David Caldwell <david@porkrind.org>
Date: Mon, 7 Oct 2024 00:11:07 -0700
Subject: [PATCH] Add "DROP TYPE" support.

See: https://www.postgresql.org/docs/current/sql-droptype.html
     https://learn.microsoft.com/en-us/sql/t-sql/statements/drop-type-transact-sql?view=sql-server-ver16
     https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/DROP-TYPE.html
---
 src/ast/mod.rs            |  2 ++
 src/parser/mod.rs         |  4 ++-
 tests/sqlparser_common.rs | 54 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/src/ast/mod.rs b/src/ast/mod.rs
index a11fa63f4..b79fc1f71 100644
--- a/src/ast/mod.rs
+++ b/src/ast/mod.rs
@@ -5713,6 +5713,7 @@ pub enum ObjectType {
     Role,
     Sequence,
     Stage,
+    Type,
 }
 
 impl fmt::Display for ObjectType {
@@ -5726,6 +5727,7 @@ impl fmt::Display for ObjectType {
             ObjectType::Role => "ROLE",
             ObjectType::Sequence => "SEQUENCE",
             ObjectType::Stage => "STAGE",
+            ObjectType::Type => "TYPE",
         })
     }
 }
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index a4445e04d..650434a02 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -4887,6 +4887,8 @@ impl<'a> Parser<'a> {
             ObjectType::Sequence
         } else if self.parse_keyword(Keyword::STAGE) {
             ObjectType::Stage
+        } else if self.parse_keyword(Keyword::TYPE) {
+            ObjectType::Type
         } else if self.parse_keyword(Keyword::FUNCTION) {
             return self.parse_drop_function();
         } else if self.parse_keyword(Keyword::POLICY) {
@@ -4899,7 +4901,7 @@ impl<'a> Parser<'a> {
             return self.parse_drop_trigger();
         } else {
             return self.expected(
-                "TABLE, VIEW, INDEX, ROLE, SCHEMA, DATABASE, FUNCTION, PROCEDURE, STAGE, TRIGGER, SECRET or SEQUENCE after DROP",
+                "TABLE, VIEW, INDEX, ROLE, SCHEMA, DATABASE, FUNCTION, PROCEDURE, STAGE, TRIGGER, SECRET, SEQUENCE, or TYPE after DROP",
                 self.peek_token(),
             );
         };
diff --git a/tests/sqlparser_common.rs b/tests/sqlparser_common.rs
index 2677c193c..86130e84e 100644
--- a/tests/sqlparser_common.rs
+++ b/tests/sqlparser_common.rs
@@ -9648,6 +9648,60 @@ fn parse_create_type() {
     );
 }
 
+#[test]
+fn parse_drop_type() {
+    let sql = "DROP TYPE abc";
+    match verified_stmt(sql) {
+        Statement::Drop {
+            names,
+            object_type,
+            if_exists,
+            cascade,
+            ..
+        } => {
+            assert_eq_vec(&["abc"], &names);
+            assert_eq!(ObjectType::Type, object_type);
+            assert!(!if_exists);
+            assert!(!cascade);
+        }
+        _ => unreachable!(),
+    };
+
+    let sql = "DROP TYPE IF EXISTS def, magician, quaternion";
+    match verified_stmt(sql) {
+        Statement::Drop {
+            names,
+            object_type,
+            if_exists,
+            cascade,
+            ..
+        } => {
+            assert_eq_vec(&["def", "magician", "quaternion"], &names);
+            assert_eq!(ObjectType::Type, object_type);
+            assert!(if_exists);
+            assert!(!cascade);
+        }
+        _ => unreachable!(),
+    }
+
+    let sql = "DROP TYPE IF EXISTS my_type CASCADE";
+    match verified_stmt(sql) {
+        Statement::Drop {
+            names,
+            object_type,
+            if_exists,
+            cascade,
+            ..
+        } => {
+            assert_eq_vec(&["my_type"], &names);
+            assert_eq!(ObjectType::Type, object_type);
+            assert!(if_exists);
+            assert!(cascade);
+        }
+        _ => unreachable!(),
+    }
+}
+
 #[test]
 fn parse_call() {
     all_dialects().verified_stmt("CALL my_procedure()");