# Bug Report ### 🔎 Search Terms - Quick fix - code action - infer function return type <!-- What search terms did you use when trying to find an existing bug report? List them here so people in the future can find this one more easily. --> ### 🕗 Version & Regression Information TypeScript version: 4.2.0-dev.20210125 ### 💻 Code ```ts const a = async x => { return 1; } ``` Trigger the `infer function return type` fix here ### 🙁 Actual behavior This results in: ```ts const a = async x: Promise<number> => { return 1; } ``` ### 🙂 Expected behavior Instead a set of parameter parens needs to be added in this case: ```ts const a = async (x): Promise<number> => { return 1; } ```