Leave one-line functions alone

Prettier 1.10.2 Playground link

--arrow-parens always

Input:

const sha256 = (data) => crypto.createHash("sha256").update(data).digest("hex");

Output:

const sha256 = (data) =>
  crypto
    .createHash("sha256")
    .update(data)
    .digest("hex");

Expected behavior:

The input was perfectly fine as it stood; it was a nice one-liner, exactly 80 characters long. Breaking it into multiple lines just makes it less clear. Is there a specific reason prettier behaves this way?

[merlinnot]

IMO the current output is much more clean, I wouldn’t like it to be changed. It seems as a step backwards to me.

[pvdlg]

Maybe that could be implemented similarly to Arrays and Objects:

• If the user inline them and the line is shorter than printWidth => keep inlined
• If the user write them on multiple lines => keep on multiple line
• If the user inline them and the line is longer than printWidth => break into multiple line

This way users can choose for each specific case if it make much sense to write a one-liner or not.

See playground example with objects (to clarify what I mean).