[add] wordcount's reading time formatter

autoload/airline/extensions/wordcount/formatters/readingtime.vim

@@ -0,0 +1,47 @@
+" MIT License. Copyright (c) 2013-2020 Bailey Ling et al.
+" vim: et ts=2 sts=2 sw=2
+
+scriptencoding utf-8
+
+function! airline#extensions#wordcount#formatters#readingtime#update_fmt(...) abort
+  let s:fmt = get(g:, 'airline#extensions#wordcount#formatter#readingtime#fmt', 'About %s minutes')
+  let s:fmt_short = get(g:, 'airline#extensions#wordcount#formatter#readingtime#fmt_short', s:fmt ==# 'About %s minutes' ? '%sW' : s:fmt)
+endfunction
+
+" Reload format when statusline is rebuilt
+call airline#extensions#wordcount#formatters#readingtime#update_fmt()
+
+if index(g:airline_statusline_funcrefs, function('airline#extensions#wordcount#formatters#readingtime#update_fmt')) == -1
+  " only add it, if not already done
+  call airline#add_statusline_funcref(function('airline#extensions#wordcount#formatters#readingtime#update_fmt'))
+endif
+
+if match(get(v:, 'lang', ''), '\v\cC|en') > -1
+  let s:decimal_group = ','
+elseif match(get(v:, 'lang', ''), '\v\cde|dk|fr|pt') > -1
+  let s:decimal_group = '.'
+else
+  let s:decimal_group = ''
+endif
+
+function! airline#extensions#wordcount#formatters#readingtime#to_string(wordcount) abort
+  if airline#util#winwidth() > 85
+    if a:wordcount > 999
+      " Format number according to locale, e.g. German: 1.245 or English: 1,245
+      let wordcount = substitute(a:wordcount, '\d\@<=\(\(\d\{3\}\)\+\)$', s:decimal_group.'&', 'g')
+    else
+      let wordcount = a:wordcount
+    endif
+    let str = printf(s:fmt, ceil(wordcount / 200.0))
+  else
+    let str = printf(s:fmt_short, ceil(a:wordcount / 200.0))
+  endif
+
+  let str .= g:airline_symbols.space
+
+  if !empty(g:airline_right_alt_sep)
+    let str .= g:airline_right_alt_sep . g:airline_symbols.space
+  endif
+
+  return str
+endfunction