togglecomment.vim

" source: https://stackoverflow.com/a/24046914/2571881
let s:comment_map = {
    \   "c": '\/\/',
    \   "cpp": '\/\/',
    \   "go": '\/\/',
    \   "java": '\/\/',
    \   "javascript": '\/\/',
    \   "lua": '--',
    \   "scala": '\/\/',
    \   "php": '\/\/',
    \   "python": '#',
    \   "ruby": '#',
    \   "rust": '\/\/',
    \   "sh": '#',
    \   "desktop": '#',
    \   "fstab": '#',
    \   "conf": '#',
    \   "profile": '#',
    \   "bashrc": '#',
    \   "bash_profile": '#',
    \   "mail": '>',
    \   "eml": '>',
    \   "bat": 'REM',
    \   "ahk": ';',
    \   "vim": '"',
    \   "tex": '%',
    \ }

function! ToggleComment()
    if has_key(s:comment_map, &filetype)
        let comment_leader = s:comment_map[&filetype]
        if getline('.') =~ '^\s*$'
            " Skip empty line
            return
        endif
        if getline('.') =~ '^\s*' . comment_leader
            " Uncomment the line
            execute 'silent s/\v\s*\zs' . comment_leader . '\s*\ze//'
        else
            " Comment the line
            execute 'silent s/\v^(\s*)/\1' . comment_leader . ' /'
        endif
    else
        echo "No comment leader found for filetype"
    endif
endfunction

nnoremap <Leader>t :call ToggleComment()<CR>
vnoremap <Leader>t :call ToggleComment()<CR>

What are the bugs?

@mizlan

When uncomment the lines, the indent spaces is dismissed. For example,

static int do_something() {
struct dir* d = malloc(sizeof(*d));

// if (!d) {
// return -ENOMEM;
// }

After uncommented,

static int do_something() {
struct dir* d = malloc(sizeof(*d));

if (!d) {
return -ENOMEM;
}

Ah. I never addressed the uncomment portion of the original code in my diff.

Change the uncomment code to:

execute 'silent s/\v\s*\zs' . comment_leader . ' \ze//'

(i.e., change the match-any-whitespace to a match-space regex.