Import autoload/man.vim from 71bb4fd

This is the version of man.vim prior to
<https://github.com/neovim/neovim/pull/9023>.

I opened an issue for the degraded experience
<https://github.com/neovim/neovim/issues/9583>.

1 files changed, 400 insertions, 0 deletions

diff --git a/home/.config/nvim/autoload/man.vim b/home/.config/nvim/autoload/man.vim
new file mode 100644
index 00000000..7385862c
--- /dev/null
+++ b/home/.config/nvim/autoload/man.vim
@@ -0,0 +1,400 @@
+" Maintainer: Anmol Sethi <anmol@aubble.com>
+
+if exists('s:loaded_man')
+  finish
+endif
+let s:loaded_man = 1
+
+let s:find_arg = '-w'
+let s:localfile_arg = v:true  " Always use -l if possible. #6683
+let s:section_arg = '-s'
+
+function! s:init_section_flag()
+  call system(['env', 'MANPAGER=cat', 'man', s:section_arg, '1', 'man'])
+  if v:shell_error
+    let s:section_arg = '-S'
+  endif
+endfunction
+
+function! s:init() abort
+  call s:init_section_flag()
+  " TODO(nhooyr): Does `man -l` on SunOS list searched directories?
+  try
+    if !has('win32') && $OSTYPE !~? 'cygwin\|linux' && system('uname -s') =~? 'SunOS' && system('uname -r') =~# '^5'
+      let s:find_arg = '-l'
+    endif
+    " Check for -l support.
+    call s:get_page(s:get_path('', 'man'))
+  catch /E145:/
+    " Ignore the error in restricted mode
+  catch /command error .*/
+    let s:localfile_arg = v:false
+  endtry
+endfunction
+
+function! man#open_page(count, count1, mods, ...) abort
+  if a:0 > 2
+    call s:error('too many arguments')
+    return
+  elseif a:0 == 0
+    let ref = &filetype ==# 'man' ? expand('<cWORD>') : expand('<cword>')
+    if empty(ref)
+      call s:error('no identifier under cursor')
+      return
+    endif
+  elseif a:0 ==# 1
+    let ref = a:1
+  else
+    " Combine the name and sect into a manpage reference so that all
+    " verification/extraction can be kept in a single function.
+    " If a:2 is a reference as well, that is fine because it is the only
+    " reference that will match.
+    let ref = a:2.'('.a:1.')'
+  endif
+  try
+    let [sect, name] = man#extract_sect_and_name_ref(ref)
+    if a:count ==# a:count1
+      " v:count defaults to 0 which is a valid section, and v:count1 defaults to
+      " 1, also a valid section. If they are equal, count explicitly set.
+      let sect = string(a:count)
+    endif
+    let [sect, name, path] = s:verify_exists(sect, name)
+  catch
+    call s:error(v:exception)
+    return
+  endtry
+
+  call s:push_tag()
+  let bufname = 'man://'.name.(empty(sect)?'':'('.sect.')')
+
+  try
+    set eventignore+=BufReadCmd
+    if a:mods !~# 'tab' && s:find_man()
+      execute 'silent keepalt edit' fnameescape(bufname)
+    else
+      execute 'silent keepalt' a:mods 'split' fnameescape(bufname)
+    endif
+  finally
+    set eventignore-=BufReadCmd
+  endtry
+
+  try
+    let page = s:get_page(path)
+  catch
+    if a:mods =~# 'tab' || !s:find_man()
+      " a new window was opened
+      close
+    endif
+    call s:error(v:exception)
+    return
+  endtry
+
+  let b:man_sect = sect
+  call s:put_page(page)
+endfunction
+
+function! man#read_page(ref) abort
+  try
+    let [sect, name] = man#extract_sect_and_name_ref(a:ref)
+    let [sect, name, path] = s:verify_exists(sect, name)
+    let page = s:get_page(path)
+  catch
+    call s:error(v:exception)
+    return
+  endtry
+  let b:man_sect = sect
+  call s:put_page(page)
+endfunction
+
+" Handler for s:system() function.
+function! s:system_handler(jobid, data, event) dict abort
+  if a:event is# 'stdout' || a:event is# 'stderr'
+    let self[a:event] .= join(a:data, "\n")
+  else
+    let self.exit_code = a:data
+  endif
+endfunction
+
+" Run a system command and timeout after 30 seconds.
+function! s:system(cmd, ...) abort
+  let opts = {
+        \ 'stdout': '',
+        \ 'stderr': '',
+        \ 'exit_code': 0,
+        \ 'on_stdout': function('s:system_handler'),
+        \ 'on_stderr': function('s:system_handler'),
+        \ 'on_exit': function('s:system_handler'),
+        \ }
+  let jobid = jobstart(a:cmd, opts)
+
+  if jobid < 1
+    throw printf('command error %d: %s', jobid, join(a:cmd))
+  endif
+
+  let res = jobwait([jobid], 30000)
+  if res[0] == -1
+    try
+      call jobstop(jobid)
+      throw printf('command timed out: %s', join(a:cmd))
+    catch /^Vim(call):E900:/
+    endtry
+  elseif res[0] == -2
+    throw printf('command interrupted: %s', join(a:cmd))
+  endif
+  if opts.exit_code != 0
+    throw printf("command error (%d) %s: %s", jobid, join(a:cmd), substitute(opts.stderr, '\_s\+$', '', &gdefault ? '' : 'g'))
+  endif
+
+  return opts.stdout
+endfunction
+
+function! s:get_page(path) abort
+  " Respect $MANWIDTH or default to window width.
+  let manwidth = empty($MANWIDTH) ? winwidth(0) : $MANWIDTH
+  " Force MANPAGER=cat to ensure Vim is not recursively invoked (by man-db).
+  " http://comments.gmane.org/gmane.editors.vim.devel/29085
+  " Set MAN_KEEP_FORMATTING so Debian man doesn't discard backspaces.
+  let cmd = ['env', 'MANPAGER=cat', 'MANWIDTH='.manwidth, 'MAN_KEEP_FORMATTING=1', 'man']
+  return s:system(cmd + (s:localfile_arg ? ['-l', a:path] : [a:path]))
+endfunction
+
+function! s:put_page(page) abort
+  setlocal modifiable
+  setlocal noreadonly
+  silent keepjumps %delete _
+  silent put =a:page
+  while getline(1) =~# '^\s*$'
+    silent keepjumps 1delete _
+  endwhile
+  lua require("man").highlight_man_page()
+  setlocal filetype=man
+endfunction
+
+function! man#show_toc() abort
+  let bufname = bufname('%')
+  let info = getloclist(0, {'winid': 1})
+  if !empty(info) && getwinvar(info.winid, 'qf_toc') ==# bufname
+    lopen
+    return
+  endif
+
+  let toc = []
+  let lnum = 2
+  let last_line = line('$') - 1
+  while lnum && lnum < last_line
+    let text = getline(lnum)
+    if text =~# '^\%( \{3\}\)\=\S.*$'
+      call add(toc, {'bufnr': bufnr('%'), 'lnum': lnum, 'text': text})
+    endif
+    let lnum = nextnonblank(lnum + 1)
+  endwhile
+
+  call setloclist(0, toc, ' ')
+  call setloclist(0, [], 'a', {'title': 'Man TOC'})
+  lopen
+  let w:qf_toc = bufname
+endfunction
+
+" attempt to extract the name and sect out of 'name(sect)'
+" otherwise just return the largest string of valid characters in ref
+function! man#extract_sect_and_name_ref(ref) abort
+  if a:ref[0] ==# '-' " try ':Man -pandoc' with this disabled.
+    throw 'manpage name cannot start with ''-'''
+  endif
+  let ref = matchstr(a:ref, '[^()]\+([^()]\+)')
+  if empty(ref)
+    let name = matchstr(a:ref, '[^()]\+')
+    if empty(name)
+      throw 'manpage reference cannot contain only parentheses'
+    endif
+    return [get(b:, 'man_default_sects', ''), name]
+  endif
+  let left = split(ref, '(')
+  " see ':Man 3X curses' on why tolower.
+  " TODO(nhooyr) Not sure if this is portable across OSs
+  " but I have not seen a single uppercase section.
+  return [tolower(split(left[1], ')')[0]), left[0]]
+endfunction
+
+function! s:get_path(sect, name) abort
+  " Some man implementations (OpenBSD) return all available paths from the
+  " search command, so we get() the first one. #8341
+  if empty(a:sect)
+    return substitute(get(split(s:system(['man', s:find_arg, a:name])), 0, ''), '\n\+$', '', '')
+  endif
+  " '-s' flag handles:
+  "   - tokens like 'printf(echo)'
+  "   - sections starting with '-'
+  "   - 3pcap section (found on macOS)
+  "   - commas between sections (for section priority)
+  return substitute(get(split(s:system(['man', s:find_arg, s:section_arg, a:sect, a:name])), 0, ''), '\n\+$', '', '')
+endfunction
+
+function! s:verify_exists(sect, name) abort
+  try
+    let path = s:get_path(a:sect, a:name)
+  catch /^command error (/
+    try
+      let path = s:get_path(get(b:, 'man_default_sects', ''), a:name)
+    catch /^command error (/
+      let path = s:get_path('', a:name)
+    endtry
+  endtry
+  " Extract the section from the path, because sometimes the actual section is
+  " more specific than what we provided to `man` (try `:Man 3 App::CLI`).
+  " Also on linux, name seems to be case-insensitive. So for `:Man PRIntf`, we
+  " still want the name of the buffer to be 'printf'.
+  return s:extract_sect_and_name_path(path) + [path]
+endfunction
+
+let s:tag_stack = []
+
+function! s:push_tag() abort
+  let s:tag_stack += [{
+        \ 'buf':  bufnr('%'),
+        \ 'lnum': line('.'),
+        \ 'col':  col('.'),
+        \ }]
+endfunction
+
+function! man#pop_tag() abort
+  if !empty(s:tag_stack)
+    let tag = remove(s:tag_stack, -1)
+    execute 'silent' tag['buf'].'buffer'
+    call cursor(tag['lnum'], tag['col'])
+  endif
+endfunction
+
+" extracts the name and sect out of 'path/name.sect'
+function! s:extract_sect_and_name_path(path) abort
+  let tail = fnamemodify(a:path, ':t')
+  if a:path =~# '\.\%([glx]z\|bz2\|lzma\|Z\)$' " valid extensions
+    let tail = fnamemodify(tail, ':r')
+  endif
+  let sect = matchstr(tail, '\.\zs[^.]\+$')
+  let name = matchstr(tail, '^.\+\ze\.')
+  return [sect, name]
+endfunction
+
+function! s:find_man() abort
+  if &filetype ==# 'man'
+    return 1
+  elseif winnr('$') ==# 1
+    return 0
+  endif
+  let thiswin = winnr()
+  while 1
+    wincmd w
+    if &filetype ==# 'man'
+      return 1
+    elseif thiswin ==# winnr()
+      return 0
+    endif
+  endwhile
+endfunction
+
+function! s:error(msg) abort
+  redraw
+  echohl ErrorMsg
+  echon 'man.vim: ' a:msg
+  echohl None
+endfunction
+
+" see man#extract_sect_and_name_ref on why tolower(sect)
+function! man#complete(arg_lead, cmd_line, cursor_pos) abort
+  let args = split(a:cmd_line)
+  let cmd_offset = index(args, 'Man')
+  if cmd_offset > 0
+    " Prune all arguments up to :Man itself. Otherwise modifier commands like
+    " :tab, :vertical, etc. would lead to a wrong length.
+    let args = args[cmd_offset:]
+  endif
+  let l = len(args)
+  if l > 3
+    return
+  elseif l ==# 1
+    let name = ''
+    let sect = ''
+  elseif a:arg_lead =~# '^[^()]\+([^()]*$'
+    " cursor (|) is at ':Man printf(|' or ':Man 1 printf(|'
+    " The later is is allowed because of ':Man pri<TAB>'.
+    " It will offer 'priclass.d(1m)' even though section is specified as 1.
+    let tmp = split(a:arg_lead, '(')
+    let name = tmp[0]
+    let sect = tolower(get(tmp, 1, ''))
+    return s:complete(sect, '', name)
+  elseif args[1] !~# '^[^()]\+$'
+    " cursor (|) is at ':Man 3() |' or ':Man (3|' or ':Man 3() pri|'
+    " or ':Man 3() pri |'
+    return
+  elseif l ==# 2
+    if empty(a:arg_lead)
+      " cursor (|) is at ':Man 1 |'
+      let name = ''
+      let sect = tolower(args[1])
+    else
+      " cursor (|) is at ':Man pri|'
+      if a:arg_lead =~# '\/'
+        " if the name is a path, complete files
+        " TODO(nhooyr) why does this complete the last one automatically
+        return glob(a:arg_lead.'*', 0, 1)
+      endif
+      let name = a:arg_lead
+      let sect = ''
+    endif
+  elseif a:arg_lead !~# '^[^()]\+$'
+    " cursor (|) is at ':Man 3 printf |' or ':Man 3 (pr)i|'
+    return
+  else
+    " cursor (|) is at ':Man 3 pri|'
+    let name = a:arg_lead
+    let sect = tolower(args[1])
+  endif
+  return s:complete(sect, sect, name)
+endfunction
+
+function! s:complete(sect, psect, name) abort
+  try
+    let mandirs = join(split(s:system(['man', s:find_arg]), ':\|\n'), ',')
+  catch
+    call s:error(v:exception)
+    return
+  endtry
+  let pages = globpath(mandirs,'man?/'.a:name.'*.'.a:sect.'*', 0, 1)
+  " We remove duplicates in case the same manpage in different languages was found.
+  return uniq(sort(map(pages, 's:format_candidate(v:val, a:psect)'), 'i'))
+endfunction
+
+function! s:format_candidate(path, psect) abort
+  if a:path =~# '\.\%(pdf\|in\)$' " invalid extensions
+    return
+  endif
+  let [sect, name] = s:extract_sect_and_name_path(a:path)
+  if sect ==# a:psect
+    return name
+  elseif sect =~# a:psect.'.\+$'
+    " We include the section if the user provided section is a prefix
+    " of the actual section.
+    return name.'('.sect.')'
+  endif
+endfunction
+
+function! man#init_pager() abort
+  if getline(1) =~# '^\s*$'
+    silent keepjumps 1delete _
+  else
+    keepjumps 1
+  endif
+  lua require("man").highlight_man_page()
+  " This is not perfect. See `man glDrawArraysInstanced`. Since the title is
+  " all caps it is impossible to tell what the original capitilization was.
+  let ref = substitute(matchstr(getline(1), '^[^)]\+)'), ' ', '_', 'g')
+  try
+    let b:man_sect = man#extract_sect_and_name_ref(ref)[0]
+  catch
+    let b:man_sect = ''
+  endtry
+  execute 'silent file man://'.fnameescape(ref)
+endfunction
+
+call s:init()