[BUG]: Error E315 if 'splitbelow' option is set.

[VanLaser]

When using the splitbelow option, I get strange Vim internal errors (E315), for each line, when opening a help topic.

How to reproduce (minimal vimrc - I use vim-plug as plugin manager):

set nocompatible

filetype off
call plug#begin('~/.vim/plugged')
    Plug 'aserebryakov/filestyle'
call plug#end()

filetype plugin indent on
syntax on

set splitbelow

The errors look like:

:h syntax.txt
E315: ml_get: invalid lnum: 5319
E315: ml_get: invalid lnum: 5318
...
E315: ml_get: invalid lnum: 1

I suspect the wincmd w commands are to blame, but I don't know how to change them.

Thanks for the plugin!

[aserebryakov]

How critical issue is?

[aserebryakov]

The issue is confirmed (Vim 7.4 for Windows + Pathogen).

[VanLaser]

How critical issue is?

It's not critical, in that I can disable set splitbelow. It is critical, if you consider that set splitbelow is a standard Vim option that anyone should be able to use. In any case, thanks for confirming the issue.

Perhaps - just give an option not to hook/autocmd FileStyle... operations to any buffer by default, and allow/advice users how to do it selectively instead (only for their preferred filetypes)? Hooking to VimEnter etc. by default is a little intrusive. Or: avoid 'help', unlisted, or even all read-only buffers, if that's the only place where the bug appears? (just suggestions, if useful)

[aserebryakov]

I tried to reproduce the issue on Ubuntu version. It gives another error:

E434: Can't find tag pattern

[VanLaser]

I can make it happen (E315) on both Win7 x64 and ArchLinux (Vim 7.4, included patches 1-729).

[dennis-hamester]

I have the same problem and it's actually quite annoying. Similar to VanLaser, I'm also on Arch and use vim-plug. Another observation here is, that Local Additions in the help root file is empty now.
Is there anything I can do to further help / debug this issue?

[aserebryakov]

In general, errors like E315 may mean bug in Vim itself, but anyway I will try to find workaround as soon as possible.

[aserebryakov]

@VanLaser, @dennishamester , can you please provide me the .vim and .vimrc to reproduce the issue in your environment?