test for DELETE + fixes

vendored/sqlite3-parser/src/to_sql_string/stmt/create_trigger.rs

@@ -77,7 +77,7 @@ impl ToSqlString for ast::TriggerCmdDelete {
             self.where_clause
                 .as_ref()
                 .map_or("".to_string(), |expr| format!(
-                    " {}",
+                    " WHERE {}",
                     expr.to_sql_string(context)
                 ))
         )

vendored/sqlite3-parser/src/to_sql_string/stmt/delete.rs

@@ -18,13 +18,13 @@ impl ToSqlString for ast::Delete {
             self.where_clause
                 .as_ref()
                 .map_or("".to_string(), |expr| format!(
-                    " {}",
+                    " WHERE {}",
                     expr.to_sql_string(context)
                 )),
             self.returning
                 .as_ref()
                 .map_or("".to_string(), |returning| format!(
-                    " {}",
+                    " RETURNING {}",
                     returning
                         .iter()
                         .map(|col| col.to_sql_string(context))
@@ -48,3 +48,89 @@ impl ToSqlString for ast::Delete {
         )
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::to_sql_string_test;
+
+    // Basic DELETE from a single table
+    to_sql_string_test!(test_delete_all, "DELETE FROM employees;");
+
+    // DELETE with a simple WHERE clause
+    to_sql_string_test!(
+        test_delete_with_where,
+        "DELETE FROM employees WHERE id = 1;"
+    );
+
+    // DELETE with multiple WHERE conditions
+    to_sql_string_test!(
+        test_delete_with_multi_where,
+        "DELETE FROM employees WHERE salary < 50000 AND department_id = 3;"
+    );
+
+    // DELETE with IN clause
+    to_sql_string_test!(
+        test_delete_with_in,
+        "DELETE FROM employees WHERE id IN (1, 2, 3);"
+    );
+
+    // DELETE with subquery in WHERE
+    to_sql_string_test!(
+        test_delete_with_subquery,
+        "DELETE FROM employees WHERE department_id IN (SELECT id FROM departments WHERE name = 'Sales');"
+    );
+
+    // DELETE with EXISTS clause
+    to_sql_string_test!(
+        test_delete_with_exists,
+        "DELETE FROM employees WHERE EXISTS (SELECT 1 FROM orders WHERE orders.employee_id = employees.id AND orders.status = 'pending');"
+    );
+
+    // DELETE with RETURNING clause
+    to_sql_string_test!(
+        test_delete_with_returning,
+        "DELETE FROM employees WHERE salary < 30000 RETURNING id, name;"
+    );
+
+    // DELETE with LIMIT clause
+    to_sql_string_test!(
+        test_delete_with_limit,
+        "DELETE FROM employees WHERE salary < 40000 LIMIT 5;"
+    );
+
+    // DELETE with ORDER BY and LIMIT
+    to_sql_string_test!(
+        test_delete_with_order_by_limit,
+        "DELETE FROM employees WHERE salary < 40000 ORDER BY id DESC LIMIT 5;"
+    );
+
+    // DELETE from schema-qualified table
+    to_sql_string_test!(
+        test_delete_schema_qualified,
+        "DELETE FROM main.employees WHERE id = 1;"
+    );
+
+    // DELETE with BETWEEN clause
+    to_sql_string_test!(
+        test_delete_with_between,
+        "DELETE FROM employees WHERE salary BETWEEN 30000 AND 50000;"
+    );
+
+    // DELETE with NULL check
+    to_sql_string_test!(
+        test_delete_with_null,
+        "DELETE FROM employees WHERE department_id IS NULL;"
+    );
+
+    // DELETE with LIKE clause
+    to_sql_string_test!(
+        test_delete_with_like,
+        "DELETE FROM employees WHERE name LIKE 'J%';"
+    );
+
+    // DELETE with complex expression in WHERE
+    to_sql_string_test!(
+        test_delete_with_complex_expression,
+        "DELETE FROM employees WHERE (salary * 1.1) > 60000 AND department_id != 1;"
+    );
+}