fix(core): fallback to safe string payload in stringifyIO when superjson fails

Author: Tyagiquamar

packages/core/src/v3/utils/ioSerialization.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it } from "vitest";
+import { stringifyIO } from "./ioSerialization.js";
+
+describe("stringifyIO", () => {
+  it("returns undefined data for undefined input", async () => {
+    const result = await stringifyIO(undefined);
+    expect(result).toEqual({ dataType: "application/json" });
+  });
+
+  it("returns plain text for string input", async () => {
+    const result = await stringifyIO("hello world");
+    expect(result).toEqual({ data: "hello world", dataType: "text/plain" });
+  });
+
+  it("serializes normal objects using super+json", async () => {
+    const result = await stringifyIO({ key: "value", num: 42 });
+    expect(result.dataType).toEqual("application/super+json");
+    expect(typeof result.data).toBe("string");
+  });
+
+  it("fallback returns string data when superjson fails", async () => {
+    // Create an object where superjson.stringify throws or handles non-standard values
+    const cyclic: any = { name: "test" };
+    cyclic.self = cyclic;
+
+    const result = await stringifyIO(cyclic);
+    expect(typeof result.data).toBe("string");
+  });
+});

packages/core/src/v3/utils/ioSerialization.ts

@@ -96,7 +96,13 @@ export async function stringifyIO(value: any): Promise<IOPacket> {
 
     return { data, dataType: "application/super+json" };
   } catch {
-    return { data: value, dataType: "application/json" };
+    try {
+      const data = JSON.stringify(value, makeSafeReplacer());
+
+      return { data, dataType: "application/json" };
+    } catch {
+      return { data: String(value), dataType: "text/plain" };
+    }
   }
 }