fix(codegen): generate missing type in export type {} from 'mod' (#10539)

fixes #10465

Author: Boshen

crates/oxc_codegen/src/gen.rs

@@ -1038,6 +1038,10 @@ impl Gen for ExportNamedDeclaration<'_> {
                 p.needs_semicolon = false;
             }
         } else {
+            if self.export_kind.is_type() {
+                p.print_hard_space();
+                p.print_str("type");
+            }
             p.print_soft_space();
             p.print_ascii_byte(b'{');
             if !self.specifiers.is_empty() {

crates/oxc_codegen/tests/integration/tester.rs

@@ -7,7 +7,7 @@ use oxc_span::SourceType;
 pub fn test_with_parse_options(source_text: &str, expected: &str, parse_options: ParseOptions) {
     let allocator = Allocator::default();
     let ret =
-        Parser::new(&allocator, source_text, SourceType::jsx()).with_options(parse_options).parse();
+        Parser::new(&allocator, source_text, SourceType::tsx()).with_options(parse_options).parse();
     let result = CodeGenerator::new().build(&ret.program).code;
     assert_eq!(result, expected, "\nfor source: {source_text}");
 }
@@ -24,7 +24,7 @@ pub fn test_same(source_text: &str) {
 
 #[track_caller]
 pub fn test_options(source_text: &str, expected: &str, options: CodegenOptions) {
-    test_options_with_source_type(source_text, expected, SourceType::jsx(), options);
+    test_options_with_source_type(source_text, expected, SourceType::tsx(), options);
 }
 
 #[track_caller]

crates/oxc_codegen/tests/integration/unit.rs

@@ -25,6 +25,13 @@ fn module_decl() {
     );
 }
 
+#[test]
+fn export_type() {
+    test_same("export type {} from \"mod\";\n");
+    test_same("export type { Foo } from \"mod\";\n");
+    test_same("export { type Foo, type Bar } from \"mod\";\n");
+}
+
 #[test]
 fn expr() {
     test("new (foo()).bar();", "new (foo()).bar();\n");