From 78500af546ea3c92f016c729e173c66fccbe46ed Mon Sep 17 00:00:00 2001
From: CPunisher <1343316114@qq.com>
Date: Fri, 25 Oct 2024 11:53:48 +0800
Subject: [PATCH] fix(typescript): Check whether the method is abstract when
 checking `is_overload` (#9678)

**Related issue:**

 - Closes https://github.com/swc-project/swc/issues/9656
---
 .changeset/fair-maps-move.md                 |  6 ++++++
 crates/swc_typescript/src/fast_dts/mod.rs    |  2 +-
 crates/swc_typescript/tests/fast_dts_deno.rs | 20 ++++++++++++++++++++
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/fair-maps-move.md

diff --git a/.changeset/fair-maps-move.md b/.changeset/fair-maps-move.md
new file mode 100644
index 00000000000..317919d90c7
--- /dev/null
+++ b/.changeset/fair-maps-move.md
@@ -0,0 +1,6 @@
+---
+swc_core: patch
+swc_typescript: patch
+---
+
+fix(typescript): Check whether the method is abstract when checking `is_overload`
diff --git a/crates/swc_typescript/src/fast_dts/mod.rs b/crates/swc_typescript/src/fast_dts/mod.rs
index 3403619bd3d..3e61548518f 100644
--- a/crates/swc_typescript/src/fast_dts/mod.rs
+++ b/crates/swc_typescript/src/fast_dts/mod.rs
@@ -758,7 +758,7 @@ impl FastDts {
                     }
                 }
                 ClassMember::Method(method) => {
-                    let is_overload = method.function.body.is_none();
+                    let is_overload = method.function.body.is_none() && !method.is_abstract;
                     if !prev_is_overload || is_overload {
                         prev_is_overload = is_overload;
                         true
diff --git a/crates/swc_typescript/tests/fast_dts_deno.rs b/crates/swc_typescript/tests/fast_dts_deno.rs
index a35dfd279eb..76eb1ca4009 100644
--- a/crates/swc_typescript/tests/fast_dts_deno.rs
+++ b/crates/swc_typescript/tests/fast_dts_deno.rs
@@ -218,6 +218,26 @@ fn dts_class_decl_prop_infer_test() {
     );
 }
 
+#[test]
+fn dts_class_abstract_method_test() {
+    transform_dts_test(
+        r#"export abstract class Manager {
+    protected abstract A(): void;
+    protected B(): void {
+        console.log("B");
+    }
+    protected C(): void {
+        console.log("B");
+    }
+}"#,
+        r#"export declare abstract class Manager {
+    protected abstract A(): void;
+    protected B(): void;
+    protected C(): void;
+}"#,
+    );
+}
+
 #[test]
 fn dts_var_decl_test() {
     transform_dts_test(