vim-asyncomplete-gitcommit-mirror/autoload/asyncomplete/sources/gitcommit.vim

function! asyncomplete#sources#gitcommit#completor(opt, ctx) abort
    let l:col = a:ctx['col']
    let l:typed = a:ctx['typed']

    let l:kw = matchstr(l:typed, '\v\S+$')
    let l:kwlen = len(l:kw)

    let l:startcol = l:col - l:kwlen

    let l:matches = [
        \ "do", "if", "in", "for", "let", "new", "try", "var", "case", "else", "enum", "eval", "null", "this", "true",
        \ "void", "with", "await", "break", "catch", "class", "const", "false", "super", "throw", "while", "yield",
        \ "delete", "export", "import", "public", "return", "static", "switch", "typeof", "default", "extends",
        \ "finally", "package", "private", "continue", "debugger", "function", "arguments", "interface", "protected",
        \ "implements", "instanceof"
        \ ]

    call asyncomplete#complete(a:opt['name'], a:ctx, l:startcol, l:matches)
endfunction