nuwiki/autoload/vimwiki/vars.vim

" autoload/vimwiki/vars.vim — compatibility shim for plugins that depend on
" the original vimwiki API (e.g. vimwiki-sync, vim-zettel).
"
" Only the subset of `vimwiki#vars#get_wikilocal` keys that third-party
" plugins are known to call is implemented here; add entries as needed.
" Values are read from nuwiki's own config variables so users don't have
" to duplicate settings.

" Per-wiki local config values.
"
" Supported keys:
"   path            — wiki root directory (with trailing slash)
"   is_temporary_wiki — always 0 for a configured wiki
"   ext / extension — file extension (default '.wiki')
"   syntax          — syntax name (default 'vimwiki')
"
" LIMITATION: the optional second argument (upstream's wiki index) is
" ignored — values always come from the scalar `g:nuwiki_*` vars, i.e.
" the first/shorthand wiki. Third-party plugins that query a specific
" wiki by index in a multi-wiki setup will get the first wiki's values.
" The shim exists for single-wiki compatibility (vimwiki-sync, vim-zettel);
" extend here with `g:nuwiki_wikis[a:1]` lookups if multi-wiki support is
" needed.
function! vimwiki#vars#get_wikilocal(key, ...) abort
  if a:key ==# 'path'
    let l:root = expand(get(g:, 'nuwiki_wiki_root', '~/vimwiki'))
    " Ensure trailing slash to match what the original vimwiki returns.
    return l:root =~# '/$' ? l:root : l:root . '/'

  elseif a:key ==# 'is_temporary_wiki'
    return 0

  elseif a:key ==# 'ext' || a:key ==# 'extension'
    let l:ext = get(g:, 'nuwiki_file_extension', '.wiki')
    return l:ext[0] ==# '.' ? l:ext : '.' . l:ext

  elseif a:key ==# 'syntax'
    return get(g:, 'nuwiki_syntax', 'vimwiki')

  endif
  return ''
endfunction

" Global (non-wiki-specific) config values.
function! vimwiki#vars#get_global(key) abort
  return ''
endfunction