From 33be08bde89cff9b9283ef933f3913dcf1e5baba Mon Sep 17 00:00:00 2001
From: Dylan Conway <35280289+dylan-conway@users.noreply.github.com>
Date: Mon, 19 May 2025 17:05:10 -0700
Subject: [PATCH] Fix RuntimeError.from return value (#19777)

Co-authored-by: claude[bot] <209825114+claude[bot]@users.noreply.github.com>
Co-authored-by: dylan-conway <dylan-conway@users.noreply.github.com>
---
 packages/bun-error/runtime-error.ts | 4 ++--
 test/js/bun/runtime-error.test.ts   | 9 +++++++++
 2 files changed, 11 insertions(+), 2 deletions(-)
 create mode 100644 test/js/bun/runtime-error.test.ts

diff --git a/packages/bun-error/runtime-error.ts b/packages/bun-error/runtime-error.ts
index 4a739edf3e..81041129d8 100644
--- a/packages/bun-error/runtime-error.ts
+++ b/packages/bun-error/runtime-error.ts
@@ -42,11 +42,11 @@ export default class RuntimeError {
   original: Error;
   stack: StackFrame[];
 
-  static from(error: Error) {
+  static from(error: Error): RuntimeError {
     const runtime = new RuntimeError();
     runtime.original = error;
     runtime.stack = this.parseStack(error);
-    return RuntimeError;
+    return runtime;
   }
 
   /**
diff --git a/test/js/bun/runtime-error.test.ts b/test/js/bun/runtime-error.test.ts
new file mode 100644
index 0000000000..36c01859de
--- /dev/null
+++ b/test/js/bun/runtime-error.test.ts
@@ -0,0 +1,9 @@
+import { expect, test } from "bun:test";
+import RuntimeError from "../../../packages/bun-error/runtime-error";
+
+test("RuntimeError.from returns instance", () => {
+  const err = new Error("boom");
+  const runtime = RuntimeError.from(err);
+  expect(runtime.original).toBe(err);
+  expect(Array.isArray(runtime.stack)).toBe(true);
+});