ale/autoload/ale/virtualtext.vim

scriptencoding utf-8
" Author: w0rp <devw0rp@gmail.com>
" Author: Luan Santos <cfcluan@gmail.com>
" Description: Shows lint message for the current line as virtualtext, if any

" Controls the milliseconds delay before showing a message.
let g:ale_virtualtext_delay = get(g:, 'ale_virtualtext_delay', 10)
let s:cursor_timer = -1
let s:last_pos = [0, 0, 0]
let s:has_virt_text = 0
let s:emulate_virt = 0

if has('nvim-0.3.2')
    let s:ns_id = nvim_create_namespace('ale')
    let s:has_virt_text = 1
elseif has('textprop') && has('popupwin')
    let s:has_virt_text = 1
    let s:emulate_virt = !has('patch-9.0.0297')
    let s:hl_list = []

    if s:emulate_virt
        call prop_type_add('ale', {})
        let s:last_virt = -1
    endif
endif

function! ale#virtualtext#Clear(buf) abort
    if !s:has_virt_text
        return
    endif

    if has('nvim')
        call nvim_buf_clear_namespace(a:buf, s:ns_id, 0, -1)
    else
        if s:emulate_virt && s:last_virt != -1
            call prop_remove({'type': 'ale'})
            call popup_close(s:last_virt)
            let s:last_virt = -1
        elseif !empty(s:hl_list)
            call prop_remove({
            \ 'types': s:hl_list,
            \ 'all': 1,
            \ 'bufnr': a:buf})
        endif
    endif
endfunction

function! ale#virtualtext#ShowMessage(message, hl_group, buf, line) abort
    if !s:has_virt_text || !bufexists(str2nr(a:buf))
        return
    endif

    let l:prefix = get(g:, 'ale_virtualtext_prefix', '> ')
    let l:msg = l:prefix.trim(substitute(a:message, '\n', ' ', 'g'))

    if has('nvim')
        call nvim_buf_set_virtual_text(a:buf, s:ns_id, a:line-1, [[l:msg, a:hl_group]], {})
    elseif s:emulate_virt
        let l:left_pad = col('$')
        call prop_add(a:line, l:left_pad, {
        \ 'type': 'ale',
        \})
        let s:last_virt = popup_create(l:msg, {
        \ 'line': -1,
        \ 'padding': [0, 0, 0, 1],
        \ 'mask': [[1, 1, 1, 1]],
        \ 'textprop': 'ale',
        \ 'highlight': a:hl_group,
        \ 'fixed': 1,
        \ 'wrap': 0,
        \ 'zindex': 2
        \})
    else
        let type = prop_type_get(a:hl_group)

        if type == {}
            call add(s:hl_list, a:hl_group)
            call prop_type_add(a:hl_group, {'highlight': a:hl_group})
        endif

        call prop_add(a:line, 0, {
        \ 'type': a:hl_group,
        \ 'text': ' ' . l:msg,
        \ 'bufnr': a:buf
        \})
    endif
endfunction

function! s:StopCursorTimer() abort
    if s:cursor_timer != -1
        call timer_stop(s:cursor_timer)
        let s:cursor_timer = -1
    endif
endfunction

function! ale#virtualtext#GetHlGroup(type, style) abort
    if a:type is# 'E'
        if a:style is# 'style'
            return 'ALEVirtualTextStyleError'
        else
            return 'ALEVirtualTextError'
        endif
    elseif a:type is# 'W'
        if a:style is# 'style'
            return 'ALEVirtualTextStyleWarning'
        else
            return 'ALEVirtualTextWarning'
        endif
    else
        return 'ALEVirtualTextInfo'
    endif
endfunction

function! ale#virtualtext#ShowCursorWarning(...) abort
    if g:ale_virtualtext_cursor != 1
        return
    endif

    let l:buffer = bufnr('')

    if mode(1) isnot# 'n'
        return
    endif

    if ale#ShouldDoNothing(l:buffer)
        return
    endif

    let [l:info, l:loc] = ale#util#FindItemAtCursor(l:buffer)

    call ale#virtualtext#Clear(l:buffer)

    if !empty(l:loc)
        let l:msg = l:loc.text
        let l:type = get(l:loc, 'type', 'E')
        let l:style = get(l:loc, 'sub_type', '')
        let l:hl_group = ale#virtualtext#GetHlGroup(l:type, l:style)
        call ale#virtualtext#ShowMessage(l:msg, l:hl_group, l:buffer, line('.'))
    endif
endfunction

function! ale#virtualtext#ShowCursorWarningWithDelay() abort
    let l:buffer = bufnr('')

    if g:ale_virtualtext_cursor != 1
        return
    endif

    if mode(1) isnot# 'n'
        return
    endif

    call s:StopCursorTimer()

    let l:pos = getpos('.')[0:2]

    " Check the current buffer, line, and column number against the last
    " recorded position. If the position has actually changed, *then*
    " we should show something. Otherwise we can end up doing processing
    " the show message far too frequently.
    if l:pos != s:last_pos
        let l:delay = ale#Var(l:buffer, 'virtualtext_delay')

        let s:last_pos = l:pos
        let s:cursor_timer = timer_start(
        \   l:delay,
        \   function('ale#virtualtext#ShowCursorWarning')
        \)
    endif
endfunction

function! ale#virtualtext#SetTexts(buf, loclist) abort
    if !has('nvim') && s:emulate_virt
        return
    endif

    call ale#virtualtext#Clear(a:buf)

    for l in a:loclist
        if l['bufnr'] != a:buf
            continue
        endif

        let hl = ale#virtualtext#GetHlGroup(l['type'], get(l, 'sub_type', ''))
        call ale#virtualtext#ShowMessage(l['text'], hl, a:buf, l['lnum'])
    endfor
endfunction