Error when directory name contains underscore

[vid512]

I've created minimal test project. This is on Windows. All files reside in directory d:\_t.

meson.build:

project('foo', 'cpp')
executable('foo', 'foo.cpp')

foo.cpp

int main() {
	return 0;
}

When I open foo.cpp in NeoVim with Mesonic installed, it throws an error while opening the file:

Error detected whiler processing BufReadPost Autocommands for "*"..script C:\Users\...\AppData\Local\nvim-data\lazy\mesonic\compiler\meson.vim[85]..function <SNR>33_SetErrorFormat[15]..<SNR>33_GetCwdRelativeToProjectDirectory:
line 1:
E877: (NFA regexp) Invalid character class 116

Note that character 116 = t. If you rename the directory to _x, the error goes away.

The error also happens with _b (character 98), but not with _a, etc...

[igankevich]

@vid512 Does it work if _t directory is not at the root of the drive?

For example: D:\some-dir\_t?

[vid512]

Same problem. Combination of directory name starting with underscore + some characters (t, b, ...) anywhere in path seems to trigger this. Also D:\some-dir\_t\somedir, D:\a\_test\b, etc. However, I couldn't replicate this with underscore in the middle of directory name, only at the beginning.

[vid512]

Problem is in function GetCwdRelativeToProjectDirectory.

https://github.com/igankevich/mesonic/blob/69a3a1e03b94d4d41f94dfe243edbe87069c22f1/compiler/meson.vim#L10-L12

The fnameescape apparently doesn't escape good enough for substitute.

I was able to get rid of the bug by changing the function to this code:

function! s:GetCwdRelativeToProjectDirectory(project_dir)
    let l:cwd = getcwd() 
    if l:cwd[0:len(a:project_dir)-1] ==# a:project_dir
        return l:cwd[len(a:project_dir)]
    else
        return l:cwd
    endif
endfunction

(Make sure to check the code for any pitfalls. I know next to nothing about vimscript.)

[igankevich]

I was able to get rid of the bug by changing the function to this code:

Thank you! I fixed this issue in https://github.com/igankevich/mesonic/commit/d6780c3af29ebfc8c631399b2692b928da9bf7bd. Better late than never I guess.