From 636585b44d0f74f457b44766f8d6fda68bcc4c09 Mon Sep 17 00:00:00 2001
From: David Sherret <dsherret@users.noreply.github.com>
Date: Mon, 29 Jul 2024 21:36:17 -0400
Subject: [PATCH] fix(es/codegen): Emit question token for class methods
 (#9342)

---
 .changeset/tall-cooks-speak.md                              | 6 ++++++
 crates/swc_ecma_codegen/src/lib.rs                          | 4 ++++
 .../tests/fixture/typescript/class_method/input.js          | 2 +-
 .../tests/fixture/typescript/class_method/output.js         | 2 +-
 .../tests/fixture/typescript/class_method/output.min.js     | 2 +-
 crates/swc_ecma_transforms_typescript/src/strip_type.rs     | 1 +
 6 files changed, 14 insertions(+), 3 deletions(-)
 create mode 100644 .changeset/tall-cooks-speak.md

diff --git a/.changeset/tall-cooks-speak.md b/.changeset/tall-cooks-speak.md
new file mode 100644
index 000000000000..bc3b06eae02b
--- /dev/null
+++ b/.changeset/tall-cooks-speak.md
@@ -0,0 +1,6 @@
+---
+swc_ecma_codegen: patch
+swc_ecma_transforms_typescript: patch
+---
+
+fix(es/codegen): Emit question token for class methods
diff --git a/crates/swc_ecma_codegen/src/lib.rs b/crates/swc_ecma_codegen/src/lib.rs
index 3a9737fef6c5..f2901a69464a 100644
--- a/crates/swc_ecma_codegen/src/lib.rs
+++ b/crates/swc_ecma_codegen/src/lib.rs
@@ -1599,6 +1599,10 @@ where
             }
         }
 
+        if n.is_optional {
+            punct!("?");
+        }
+
         if let Some(type_params) = &n.function.type_params {
             emit!(type_params);
         }
diff --git a/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/input.js b/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/input.js
index 8ae861559ba8..51baf161b6b8 100644
--- a/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/input.js
+++ b/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/input.js
@@ -1,5 +1,5 @@
 class MyClass extends Base {
     public override method(param: number): string {
     }
-    public abstract override log(msg: string): void;
+    public abstract override log?<TValue>(msg: string): TValue;
 }
diff --git a/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.js b/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.js
index afa69c78aceb..d2efd95d7ba3 100644
--- a/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.js
+++ b/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.js
@@ -1,4 +1,4 @@
 class MyClass extends Base {
     public override method(param: number): string {}
-    public abstract override log(msg: string): void;
+    public abstract override log?<TValue>(msg: string): TValue;
 }
diff --git a/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.min.js b/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.min.js
index c59261408b32..69933daf3dbc 100644
--- a/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.min.js
+++ b/crates/swc_ecma_codegen/tests/fixture/typescript/class_method/output.min.js
@@ -1 +1 @@
-class MyClass extends Base{public override method(param:number):string{}public abstract override log(msg:string):void}
+class MyClass extends Base{public override method(param:number):string{}public abstract override log?<TValue>(msg:string):TValue}
diff --git a/crates/swc_ecma_transforms_typescript/src/strip_type.rs b/crates/swc_ecma_transforms_typescript/src/strip_type.rs
index 12c7e96ca93a..a6d0a6429263 100644
--- a/crates/swc_ecma_transforms_typescript/src/strip_type.rs
+++ b/crates/swc_ecma_transforms_typescript/src/strip_type.rs
@@ -84,6 +84,7 @@ impl VisitMut for StripType {
         n.accessibility = None;
         n.is_override = false;
         n.is_abstract = false;
+        n.is_optional = false;
         n.visit_mut_children_with(self);
     }