Unexpected E303 after updating Vim

[lkintact]

Steps to reproduce

I tried updating Vim from version 9.0.2103 to 9.1.274, and after that it started emitting an E303 error every time I open a file.
I didn't change any settings in _vimrc.

Expected behaviour

Vim should not emit the error, should create a swap file.

Version of Vim

9.1.274

Environment

OS: Windows 10
Terminal: GUI.

Logs and stack traces

No response

[chrisbra]

we didn't make any changes to swap file handling. So that is puzzling. Can you check if it works with gvim --clean?

[lkintact]

With gvim --clean gVim doesn't emit the error.

[lkintact]

It probably matters: the value of the directory option in _vimrc is %HOMEDRIVE%\%HOMEPATH%\vimfiles\swap.

[lkintact]

It does matter: changing directory to C:\Users\admin1\vimfiles\swap (i.e, I expanded the variables %HOMEDRIVE% and %HOMEPATH%) solved the issue.

[lkintact]

Turns out for some reason Vim 9.1.274 doesn't expand the %HOMEPATH% variable: executing :set directory? yields directory=C:\%HOMEPATH%\vimfiles\swap.

[chrisbra]

Hm, it works for me with latest installer v9.1.282. Don't know what is going on. Have you checked your environment, that `%HOMEPATH% is actually defined?

[lkintact]

I did, %HOMEPATH% is defined. Executing :echo $HOMEPATH yields \Users\admin1.

[lkintact]

I changed directory from %HOMEDRIVE%\%HOMEPATH%\vimfiles\swap to %HOMEDRIVE%%HOMEPATH%\vimfiles\swap,
(i.e. removed the backslash) and it solved the issue.

[chrisbra]

Hm, could be caused by #14161 @zeertzjq what do you think?

[zeertzjq]

Possibly. The patch was intended to restore the behavior before 1cd871b5341bf43ee99e136844e3131014880f92, which seemed to have unintentionally changed the behavior, but it has been over 19 years since then.