runtime(netrw): deprecate and remove netrwFileHandlers#Invoke()

closes: #15895

Co-authored-by: Konfekt <Konfekt@users.noreply.github.com>
Signed-off-by: Luca Saccarola <github.e41mv@aleeas.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/autoload/netrw.vim b/runtime/autoload/netrw.vim
index d09299a..0adcc65 100644
--- a/runtime/autoload/netrw.vim
+++ b/runtime/autoload/netrw.vim
@@ -4,8 +4,8 @@
 " Date:		  May 03, 2023
 " Version:	173a
 " Last Change: {{{1
-" 	2023 Nov 21 by Vim Project: ignore wildignore when expanding $COMSPEC	(v173a)
-" 	2023 Nov 22 by Vim Project: fix handling of very long filename on longlist style	(v173a)
+"   2023 Nov 21 by Vim Project: ignore wildignore when expanding $COMSPEC	(v173a)
+"   2023 Nov 22 by Vim Project: fix handling of very long filename on longlist style	(v173a)
 "   2024 Feb 19 by Vim Project: (announce adoption)
 "   2024 Feb 29 by Vim Project: handle symlinks in tree mode correctly
 "   2024 Apr 03 by Vim Project: detect filetypes for remote edited files
@@ -26,6 +26,7 @@
 "   2024 Sep 15 by Vim Project: more strict confirmation dialog (#15680)
 "   2024 Sep 19 by Vim Project: mf-selection highlight uses wrong pattern (#15700)
 "   2024 Sep 21 by Vim Project: remove extraneous closing bracket (#15718)
+"   2024 Oct 21 by Vim Project: remove netrwFileHandlers (#15895)
 "   }}}
 " Former Maintainer:	Charles E Campbell
 " GetLatestVimScripts: 1075 1 :AutoInstall: netrw.vim
@@ -5448,11 +5449,7 @@
 
   " execute the file handler
 "  call Decho("execute the file handler (if any)",'~'.expand("<slnum>"))
-  if exists("g:netrw_browsex_viewer") && g:netrw_browsex_viewer == '-'
-"   call Decho("(netrw#BrowseX) g:netrw_browsex_viewer<".g:netrw_browsex_viewer.">",'~'.expand("<slnum>"))
-   let ret= netrwFileHandlers#Invoke(exten,fname)
-
-  elseif exists("g:netrw_browsex_viewer") && executable(viewer)
+  if exists("g:netrw_browsex_viewer") && executable(viewer)
 "   call Decho("(netrw#BrowseX) g:netrw_browsex_viewer<".g:netrw_browsex_viewer.">",'~'.expand("<slnum>"))
    call s:NetrwExe("sil !".viewer." ".viewopt.s:ShellEscape(fname,1).redir)
    let ret= v:shell_error
@@ -5518,17 +5515,13 @@
 "   call Decho("(netrw#BrowseX) macunix and open",'~'.expand("<slnum>"))
    call s:NetrwExe("sil !open ".s:ShellEscape(fname,1)." ".redir)
    let ret= v:shell_error
-
   else
-   " netrwFileHandlers#Invoke() always returns 0
-"   call Decho("(netrw#BrowseX) use netrwFileHandlers",'~'.expand("<slnum>"))
-   let ret= netrwFileHandlers#Invoke(exten,fname)
+   call netrw#ErrorMsg(s:ERROR, "Couldn't find a program to open '".a:fname."'", 0)
+   let ret=0
   endif
 
-  " if unsuccessful, attempt netrwFileHandlers#Invoke()
   if ret
-"   call Decho("(netrw#BrowseX) ret=".ret," indicates unsuccessful thus far",'~'.expand("<slnum>"))
-   let ret= netrwFileHandlers#Invoke(exten,fname)
+   call netrw#ErrorMsg(s:ERROR, "Failed to open '".a:fname."'", 0)
   endif
 
   " restoring redraw! after external file handlers
diff --git a/runtime/autoload/netrwFileHandlers.vim b/runtime/autoload/netrwFileHandlers.vim
deleted file mode 100644
index 2b6f8f7..0000000
--- a/runtime/autoload/netrwFileHandlers.vim
+++ /dev/null
@@ -1,363 +0,0 @@
-" netrwFileHandlers: contains various extension-based file handlers for
-"                    netrw's browsers' x command ("eXecute launcher")
-" Maintainer: This runtime file is looking for a new maintainer.
-" Original Author: Charles E. Campbell
-" Date:		Sep 18, 2020
-" Version:	11
-" Copyright:    Copyright (C) 1999-2012 Charles E. Campbell {{{1
-"               Permission is hereby granted to use and distribute this code,
-"               with or without modifications, provided that this copyright
-"               notice is copied with it. Like anything else that's free,
-"               netrwFileHandlers.vim is provided *as is* and comes with no
-"               warranty of any kind, either expressed or implied. In no
-"               event will the copyright holder be liable for any damages
-"               resulting from the use of this software.
-"
-" Rom 6:23 (WEB) For the wages of sin is death, but the free gift of God {{{1
-"                is eternal life in Christ Jesus our Lord.
-
-" ---------------------------------------------------------------------
-" Load Once: {{{1
-if exists("g:loaded_netrwFileHandlers") || &cp
- finish
-endif
-let g:loaded_netrwFileHandlers= "v11"
-if v:version < 702
- echohl WarningMsg
- echo "***warning*** this version of netrwFileHandlers needs vim 7.2"
- echohl Normal
- finish
-endif
-let s:keepcpo= &cpo
-set cpo&vim
-
-" ---------------------------------------------------------------------
-" netrwFileHandlers#Invoke: {{{1
-fun! netrwFileHandlers#Invoke(exten,fname)
-"  call Dfunc("netrwFileHandlers#Invoke(exten<".a:exten."> fname<".a:fname.">)")
-  let exten= a:exten
-  " list of supported special characters.  Consider rcs,v --- that can be
-  " supported with a NFH_rcsCOMMAv() handler
-  if exten =~ '[@:,$!=\-+%?;~]'
-   let specials= {
-\   '@' : 'AT',
-\   ':' : 'COLON',
-\   ',' : 'COMMA',
-\   '$' : 'DOLLAR',
-\   '!' : 'EXCLAMATION',
-\   '=' : 'EQUAL',
-\   '-' : 'MINUS',
-\   '+' : 'PLUS',
-\   '%' : 'PERCENT',
-\   '?' : 'QUESTION',
-\   ';' : 'SEMICOLON',
-\   '~' : 'TILDE'}
-   let exten= substitute(a:exten,'[@:,$!=\-+%?;~]','\=specials[submatch(0)]','ge')
-"   call Decho('fname<'.fname.'> done with dictionary')
-  endif
-
-  if a:exten != "" && exists("*NFH_".exten)
-   " support user NFH_*() functions
-"   call Decho("let ret= netrwFileHandlers#NFH_".a:exten.'("'.fname.'")')
-   exe "let ret= NFH_".exten.'("'.a:fname.'")'
-  elseif a:exten != "" && exists("*s:NFH_".exten)
-   " use builtin-NFH_*() functions
-"   call Decho("let ret= netrwFileHandlers#NFH_".a:exten.'("'.fname.'")')
-   exe "let ret= s:NFH_".a:exten.'("'.a:fname.'")'
-  endif
-
-"  call Dret("netrwFileHandlers#Invoke 0 : ret=".ret)
-  return 0
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_html: handles html when the user hits "x" when the {{{1
-"                        cursor is atop a *.html file
-fun! s:NFH_html(pagefile)
-"  call Dfunc("s:NFH_html(".a:pagefile.")")
-
-  let page= substitute(a:pagefile,'^','file://','')
-
-  if executable("mozilla")
-"   call Decho("executing !mozilla ".page)
-   exe "!mozilla ".shellescape(page,1)
-  elseif executable("netscape")
-"   call Decho("executing !netscape ".page)
-   exe "!netscape ".shellescape(page,1)
-  else
-"   call Dret("s:NFH_html 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_html 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_htm: handles html when the user hits "x" when the {{{1
-"                        cursor is atop a *.htm file
-fun! s:NFH_htm(pagefile)
-"  call Dfunc("s:NFH_htm(".a:pagefile.")")
-
-  let page= substitute(a:pagefile,'^','file://','')
-
-  if executable("mozilla")
-"   call Decho("executing !mozilla ".page)
-   exe "!mozilla ".shellescape(page,1)
-  elseif executable("netscape")
-"   call Decho("executing !netscape ".page)
-   exe "!netscape ".shellescape(page,1)
-  else
-"   call Dret("s:NFH_htm 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_htm 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_jpg: {{{1
-fun! s:NFH_jpg(jpgfile)
-"  call Dfunc("s:NFH_jpg(jpgfile<".a:jpgfile.">)")
-
-  if executable("gimp")
-   exe "silent! !gimp -s ".shellescape(a:jpgfile,1)
-  elseif executable(expand("$SystemRoot")."/SYSTEM32/MSPAINT.EXE")
-"   call Decho("silent! !".expand("$SystemRoot")."/SYSTEM32/MSPAINT ".escape(a:jpgfile," []|'"))
-   exe "!".expand("$SystemRoot")."/SYSTEM32/MSPAINT ".shellescape(a:jpgfile,1)
-  else
-"   call Dret("s:NFH_jpg 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_jpg 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_gif: {{{1
-fun! s:NFH_gif(giffile)
-"  call Dfunc("s:NFH_gif(giffile<".a:giffile.">)")
-
-  if executable("gimp")
-   exe "silent! !gimp -s ".shellescape(a:giffile,1)
-  elseif executable(expand("$SystemRoot")."/SYSTEM32/MSPAINT.EXE")
-   exe "silent! !".expand("$SystemRoot")."/SYSTEM32/MSPAINT ".shellescape(a:giffile,1)
-  else
-"   call Dret("s:NFH_gif 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_gif 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_png: {{{1
-fun! s:NFH_png(pngfile)
-"  call Dfunc("s:NFH_png(pngfile<".a:pngfile.">)")
-
-  if executable("gimp")
-   exe "silent! !gimp -s ".shellescape(a:pngfile,1)
-  elseif executable(expand("$SystemRoot")."/SYSTEM32/MSPAINT.EXE")
-   exe "silent! !".expand("$SystemRoot")."/SYSTEM32/MSPAINT ".shellescape(a:pngfile,1)
-  else
-"   call Dret("s:NFH_png 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_png 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_pnm: {{{1
-fun! s:NFH_pnm(pnmfile)
-"  call Dfunc("s:NFH_pnm(pnmfile<".a:pnmfile.">)")
-
-  if executable("gimp")
-   exe "silent! !gimp -s ".shellescape(a:pnmfile,1)
-  elseif executable(expand("$SystemRoot")."/SYSTEM32/MSPAINT.EXE")
-   exe "silent! !".expand("$SystemRoot")."/SYSTEM32/MSPAINT ".shellescape(a:pnmfile,1)
-  else
-"   call Dret("s:NFH_pnm 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_pnm 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_bmp: visualize bmp files {{{1
-fun! s:NFH_bmp(bmpfile)
-"  call Dfunc("s:NFH_bmp(bmpfile<".a:bmpfile.">)")
-
-  if executable("gimp")
-   exe "silent! !gimp -s ".a:bmpfile
-  elseif executable(expand("$SystemRoot")."/SYSTEM32/MSPAINT.EXE")
-   exe "silent! !".expand("$SystemRoot")."/SYSTEM32/MSPAINT ".shellescape(a:bmpfile,1)
-  else
-"   call Dret("s:NFH_bmp 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_bmp 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_pdf: visualize pdf files {{{1
-fun! s:NFH_pdf(pdf)
-"  call Dfunc("s:NFH_pdf(pdf<".a:pdf.">)")
-  if executable("gs")
-   exe 'silent! !gs '.shellescape(a:pdf,1)
-  elseif executable("pdftotext")
-   exe 'silent! pdftotext -nopgbrk '.shellescape(a:pdf,1)
-  else
-"  call Dret("s:NFH_pdf 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_pdf 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_doc: visualize doc files {{{1
-fun! s:NFH_doc(doc)
-"  call Dfunc("s:NFH_doc(doc<".a:doc.">)")
-
-  if executable("oowriter")
-   exe 'silent! !oowriter '.shellescape(a:doc,1)
-   redraw!
-  else
-"  call Dret("s:NFH_doc 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_doc 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_sxw: visualize sxw files {{{1
-fun! s:NFH_sxw(sxw)
-"  call Dfunc("s:NFH_sxw(sxw<".a:sxw.">)")
-
-  if executable("oowriter")
-   exe 'silent! !oowriter '.shellescape(a:sxw,1)
-   redraw!
-  else
-"   call Dret("s:NFH_sxw 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_sxw 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_xls: visualize xls files {{{1
-fun! s:NFH_xls(xls)
-"  call Dfunc("s:NFH_xls(xls<".a:xls.">)")
-
-  if executable("oocalc")
-   exe 'silent! !oocalc '.shellescape(a:xls,1)
-   redraw!
-  else
-"  call Dret("s:NFH_xls 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_xls 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_ps: handles PostScript files {{{1
-fun! s:NFH_ps(ps)
-"  call Dfunc("s:NFH_ps(ps<".a:ps.">)")
-  if executable("gs")
-"   call Decho("exe silent! !gs ".a:ps)
-   exe "silent! !gs ".shellescape(a:ps,1)
-   redraw!
-  elseif executable("ghostscript")
-"   call Decho("exe silent! !ghostscript ".a:ps)
-   exe "silent! !ghostscript ".shellescape(a:ps,1)
-   redraw!
-  elseif executable("gswin32")
-"   call Decho("exe silent! !gswin32 ".shellescape(a:ps,1))
-   exe "silent! !gswin32 ".shellescape(a:ps,1)
-   redraw!
-  else
-"   call Dret("s:NFH_ps 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_ps 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_eps: handles encapsulated PostScript files {{{1
-fun! s:NFH_eps(eps)
-"  call Dfunc("s:NFH_eps()")
-  if executable("gs")
-   exe "silent! !gs ".shellescape(a:eps,1)
-   redraw!
-  elseif executable("ghostscript")
-   exe "silent! !ghostscript ".shellescape(a:eps,1)
-   redraw!
-  elseif executable("ghostscript")
-   exe "silent! !ghostscript ".shellescape(a:eps,1)
-   redraw!
-  elseif executable("gswin32")
-   exe "silent! !gswin32 ".shellescape(a:eps,1)
-   redraw!
-  else
-"   call Dret("s:NFH_eps 0")
-   return 0
-  endif
-"  call Dret("s:NFH_eps 0")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_fig: handles xfig files {{{1
-fun! s:NFH_fig(fig)
-"  call Dfunc("s:NFH_fig()")
-  if executable("xfig")
-   exe "silent! !xfig ".a:fig
-   redraw!
-  else
-"   call Dret("s:NFH_fig 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_fig 1")
-  return 1
-endfun
-
-" ---------------------------------------------------------------------
-" s:NFH_obj: handles tgif's obj files {{{1
-fun! s:NFH_obj(obj)
-"  call Dfunc("s:NFH_obj()")
-  if has("unix") && executable("tgif")
-   exe "silent! !tgif ".a:obj
-   redraw!
-  else
-"   call Dret("s:NFH_obj 0")
-   return 0
-  endif
-
-"  call Dret("s:NFH_obj 1")
-  return 1
-endfun
-
-let &cpo= s:keepcpo
-unlet s:keepcpo
-" ---------------------------------------------------------------------
-"  Modelines: {{{1
-"  vim: fdm=marker