From 99e038cfc0e876f126fda2a00f365d6d62c657ad Mon Sep 17 00:00:00 2001
From: Dunqing <dengqing0821@gmail.com>
Date: Tue, 16 Apr 2024 18:33:13 +0800
Subject: [PATCH] fix(transformer/typescript): modifiers should not be removed
 (#3005)

`codegen` relies on the modifier to decide whether to print or not. For
example, if declare is present, nothing will be printed if typescript is
not enabled.

We may need to solve this problem in a way that doesn't rely on
modifers.
---
 .../oxc_transformer/src/typescript/annotations.rs | 15 ++++-----------
 tasks/transform_conformance/babel.snap.md         |  6 ++----
 2 files changed, 6 insertions(+), 15 deletions(-)

diff --git a/crates/oxc_transformer/src/typescript/annotations.rs b/crates/oxc_transformer/src/typescript/annotations.rs
index 53081960f..63f1bb943 100644
--- a/crates/oxc_transformer/src/typescript/annotations.rs
+++ b/crates/oxc_transformer/src/typescript/annotations.rs
@@ -88,15 +88,10 @@ impl<'a> TypeScriptAnnotations<'a> {
 
                     decl.export_kind.is_type()
                         || ((decl.declaration.is_none()
-                            || decl.declaration.as_ref().is_some_and(|d| {
-                                d.modifiers().is_some_and(|modifiers| {
-                                    modifiers.contains(ModifierKind::Declare)
-                                }) || matches!(
-                                    d,
-                                    Declaration::TSInterfaceDeclaration(_)
-                                        | Declaration::TSTypeAliasDeclaration(_)
-                                )
-                            }))
+                            || decl
+                                .declaration
+                                .as_ref()
+                                .is_some_and(Declaration::is_typescript_syntax))
                             && decl.specifiers.is_empty())
                 }
                 ModuleDeclaration::ImportDeclaration(decl) => {
@@ -196,7 +191,6 @@ impl<'a> TypeScriptAnnotations<'a> {
         class.type_parameters = None;
         class.super_type_parameters = None;
         class.implements = None;
-        class.modifiers.remove_type_modifiers();
     }
 
     pub fn transform_class_body(&mut self, body: &mut ClassBody<'a>) {
@@ -236,7 +230,6 @@ impl<'a> TypeScriptAnnotations<'a> {
         func.this_param = None;
         func.type_parameters = None;
         func.return_type = None;
-        func.modifiers.remove_type_modifiers();
     }
 
     pub fn transform_jsx_opening_element(&mut self, elem: &mut JSXOpeningElement<'a>) {
diff --git a/tasks/transform_conformance/babel.snap.md b/tasks/transform_conformance/babel.snap.md
index fda77b857..532f9d6dc 100644
--- a/tasks/transform_conformance/babel.snap.md
+++ b/tasks/transform_conformance/babel.snap.md
@@ -1,4 +1,4 @@
-Passed: 134/217
+Passed: 136/217
 
 # All Passed:
 * babel-plugin-transform-react-jsx-source
@@ -16,7 +16,7 @@ Passed: 134/217
 * opts/optimizeConstEnums/input.ts
 * opts/rewriteImportExtensions/input.ts
 
-# babel-plugin-transform-typescript (80/147)
+# babel-plugin-transform-typescript (82/147)
 * class/abstract-allowDeclareFields-false/input.ts
 * class/abstract-allowDeclareFields-true/input.ts
 * class/abstract-class-decorated/input.ts
@@ -31,9 +31,7 @@ Passed: 134/217
 * class/parameter-properties-with-super/input.ts
 * class/private-method-override-transform-private/input.ts
 * class/transform-properties-declare-wrong-order/input.ts
-* declarations/erased/input.ts
 * declarations/nested-namespace/input.mjs
-* exports/declare-shadowed/input.ts
 * exports/declared-types/input.ts
 * exports/export-const-enums/input.ts
 * exports/export-type-star-from/input.ts