Short line length and member constraint leads to invalid code

[Smaug123]

Issue created from fantomas-online

Code

type Bar = | Bar of int
and Foo<'ret> = abstract Barrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr<'a> : 'a -> 'ret when 'a : comparison

Error

Fantomas was able to format the code but the result appears to be invalid F# code.
Please open an issue.

Formatted result:

type Bar =
    Bar of
        int

and Foo<'ret> =
    abstract Barrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr<'a> :
        'a -> 'ret
    when 'a: comparison

Problem description

This happens when the line is too long to accommodate the when 'a : comparison.
(This isn't blocking for G-Research; we'll just .fantomasignore it until it's fixed.)

Extra information

• [/] The formatted result breaks by code.
• The formatted result gives compiler warnings.
• I or my company would be willing to help fix this.

Options

Fantomas Master at 01/23/2021 17:11:48 - 6d75fff

    { config with
                MaxLineLength = 10 }

_{Did you know that you can ignore files when formatting from fantomas-tool or the FAKE targets by using a .fantomasignore file?}