Use the correct buffer when running in an autocmd

In an autocmd (e.g., BufNew), `%` may not be the buffer being processed.
Use `<afile>` and `<abuf>` in those cases instead.

Author: cxw42

plugin/editorconfig.vim

@@ -91,23 +91,24 @@ let s:initialized = 0
 " }}}1
 
 " shellslash handling {{{1
-function! s:DisableShellSlash() " {{{2
+function! s:DisableShellSlash(bufnr) " {{{2
     " disable shellslash for proper escaping of Windows paths
 
     " In Windows, 'shellslash' also changes the behavior of 'shellescape'.
     " It makes 'shellescape' behave like in UNIX environment. So ':setl
     " noshellslash' before evaluating 'shellescape' and restore the
     " settings afterwards when 'shell' does not contain 'sh' somewhere.
-    if has('win32') && empty(matchstr(&shell, 'sh'))
-        let s:old_shellslash = &l:shellslash
-        setlocal noshellslash
+    let l:shell = getbufvar(a:bufnr, '&shell')
+    if has('win32') && empty(matchstr(l:shell, 'sh'))
+        let s:old_shellslash = getbufvar(a:bufnr, '&shellslash')
+        setbufvar(a:bufnr, '&shellslash', 0)
     endif
 endfunction " }}}2
 
-function! s:ResetShellSlash() " {{{2
+function! s:ResetShellSlash(bufnr) " {{{2
     " reset shellslash to the user-set value, if any
     if exists('s:old_shellslash')
-        let &l:shellslash = s:old_shellslash
+        setbufvar(a:bufnr, '&shellslash', s:old_shellslash)
         unlet! s:old_shellslash
     endif
 endfunction " }}}2
@@ -204,9 +205,20 @@ function! s:GetFilenames(path, filename) " {{{1
     return l:path_list
 endfunction " }}}1
 
-function! s:UseConfigFiles() abort " Apply config to the current buffer {{{1
-    call setbufvar('%', 'editorconfig_tried', 1)
-    let l:buffer_name = expand('%:p')
+function! s:UseConfigFiles(from_autocmd) abort " Apply config to the current buffer {{{1
+    " from_autocmd is truthy if called from an autocmd, falsy otherwise.
+
+    " Get the properties of the buffer we are working on
+    if a:from_autocmd
+        let l:bufnr = str2nr(expand('<abuf>'))
+        let l:buffer_name = expand('<afile>:p')
+        let l:buffer_path = expand('<afile>:p:h')
+    else
+        let l:bufnr = bufnr('%')
+        let l:buffer_name = expand('%:p')
+        let l:buffer_path = expand('%:p:h')
+    endif
+    call setbufvar(l:bufnr, 'editorconfig_tried', 1)
 
     " Only process normal buffers (do not treat help files as '.txt' files)
     " When starting Vim with a directory, the buftype might not yet be set:
@@ -226,7 +238,7 @@ function! s:UseConfigFiles() abort " Apply config to the current buffer {{{1
         endif
     endif
 
-    if getbufvar('%', 'EditorConfig_disable', 0)
+    if getbufvar(l:bufnr, 'EditorConfig_disable', 0)
         if g:EditorConfig_verbose
             echo 'EditorConfig disabled --- skipping buffer "' . l:buffer_name . '"'
         endif
@@ -245,7 +257,7 @@ function! s:UseConfigFiles() abort " Apply config to the current buffer {{{1
     endfor
 
     " Check if any .editorconfig does exist
-    let l:conf_files = s:GetFilenames(expand('%:p:h'), '.editorconfig')
+    let l:conf_files = s:GetFilenames(l:buffer_path, '.editorconfig')
     let l:conf_found = 0
     for conf_file in conf_files
         if filereadable(conf_file)
@@ -269,12 +281,12 @@ function! s:UseConfigFiles() abort " Apply config to the current buffer {{{1
     endif
 
     if s:editorconfig_core_mode ==? 'vim_core'
-        if s:UseConfigFiles_VimCore(l:buffer_name) == 0
-            call setbufvar('%', 'editorconfig_applied', 1)
+        if s:UseConfigFiles_VimCore(l:bufnr, l:buffer_name) == 0
+            call setbufvar(l:bufnr, 'editorconfig_applied', 1)
         endif
     elseif s:editorconfig_core_mode ==? 'external_command'
-        call s:UseConfigFiles_ExternalCommand(l:buffer_name)
-        call setbufvar('%', 'editorconfig_applied', 1)
+        call s:UseConfigFiles_ExternalCommand(l:bufnr, l:buffer_name)
+        call setbufvar(l:bufnr, 'editorconfig_applied', 1)
     else
         echohl Error |
                     \ echo "Unknown EditorConfig Core: " .
@@ -290,8 +302,8 @@ function! s:EditorConfigEnable(should_enable)
     augroup editorconfig
         autocmd!
         if a:should_enable
-            autocmd BufNewFile,BufReadPost,BufFilePost * call s:UseConfigFiles()
-            autocmd VimEnter,BufNew * call s:UseConfigFiles()
+            autocmd BufNewFile,BufReadPost,BufFilePost * call s:UseConfigFiles(1)
+            autocmd VimEnter,BufNew * call s:UseConfigFiles(1)
         endif
     augroup END
 endfunction
@@ -302,7 +314,7 @@ endfunction
 command! EditorConfigEnable call s:EditorConfigEnable(1)
 command! EditorConfigDisable call s:EditorConfigEnable(0)
 
-command! EditorConfigReload call s:UseConfigFiles() " Reload EditorConfig files
+command! EditorConfigReload call s:UseConfigFiles(0) " Reload EditorConfig files
 " }}}2
 
 " On startup, enable the autocommands
@@ -312,29 +324,29 @@ call s:EditorConfigEnable(1)
 
 " UseConfigFiles function for different modes {{{1
 
-function! s:UseConfigFiles_VimCore(target)
+function! s:UseConfigFiles_VimCore(bufnr, target)
 " Use the vimscript EditorConfig core
     try
         let l:config = editorconfig_core#handler#get_configurations(
             \ { 'target': a:target } )
-        call s:ApplyConfig(l:config)
+        call s:ApplyConfig(a:bufnr, l:config)
         return 0    " success
     catch
         return 1    " failure
     endtry
 endfunction
 
-function! s:UseConfigFiles_ExternalCommand(target)
+function! s:UseConfigFiles_ExternalCommand(bufnr, target)
 " Use external EditorConfig core (e.g., the C core)
 
-    call s:DisableShellSlash()
+    call s:DisableShellSlash(a:bufnr)
     let l:exec_path = shellescape(s:editorconfig_exec_path)
-    call s:ResetShellSlash()
+    call s:ResetShellSlash(a:bufnr)
 
-    call s:SpawnExternalParser(l:exec_path, a:target)
+    call s:SpawnExternalParser(a:bufnr, l:exec_path, a:target)
 endfunction
 
-function! s:SpawnExternalParser(cmd, target) " {{{2
+function! s:SpawnExternalParser(bufnr, cmd, target) " {{{2
 " Spawn external EditorConfig. Used by s:UseConfigFiles_ExternalCommand()
 
     let l:cmd = a:cmd
@@ -345,9 +357,9 @@ function! s:SpawnExternalParser(cmd, target) " {{{2
 
     let l:config = {}
 
-    call s:DisableShellSlash()
+    call s:DisableShellSlash(a:bufnr)
     let l:cmd = l:cmd . ' ' . shellescape(a:target)
-    call s:ResetShellSlash()
+    call s:ResetShellSlash(a:bufnr)
 
     let l:parsing_result = split(system(l:cmd), '\v[\r\n]+')
 
@@ -386,96 +398,102 @@ function! s:SpawnExternalParser(cmd, target) " {{{2
         let l:config[l:eq_left] = l:eq_right
     endfor
 
-    call s:ApplyConfig(l:config)
+    call s:ApplyConfig(a:bufnr, l:config)
 endfunction " }}}2
 
 " }}}1
 
-function! s:ApplyConfig(config) abort " Set the buffer options {{{1
+function! s:ApplyConfig(bufnr, config) abort " Set the buffer options {{{1
     if g:EditorConfig_verbose
         echo 'Options: ' . string(a:config)
     endif
 
     if s:IsRuleActive('indent_style', a:config)
         if a:config["indent_style"] == "tab"
-            setl noexpandtab
+            call setbufvar(a:bufnr, '&expandtab', 0)
         elseif a:config["indent_style"] == "space"
-            setl expandtab
+            call setbufvar(a:bufnr, '&expandtab', 1)
         endif
     endif
 
     if s:IsRuleActive('tab_width', a:config)
-        let &l:tabstop = str2nr(a:config["tab_width"])
+        let l:tabstop = str2nr(a:config["tab_width"])
+        call setbufvar(a:bufnr, '&tabstop', l:tabstop)
+    else
+        " Grab the current ts so we can use it below
+        let l:tabstop = getbufvar(a:bufnr, '&tabstop')
     endif
 
     if s:IsRuleActive('indent_size', a:config)
         " if indent_size is 'tab', set shiftwidth to tabstop;
         " if indent_size is a positive integer, set shiftwidth to the integer
         " value
         if a:config["indent_size"] == "tab"
-            let &l:shiftwidth = &l:tabstop
+            call setbufvar(a:bufnr, '&shiftwidth', l:tabstop)
             if type(g:EditorConfig_softtabstop_tab) != type([])
-                let &l:softtabstop = g:EditorConfig_softtabstop_tab > 0 ?
-                            \ &l:shiftwidth : g:EditorConfig_softtabstop_tab
+                call setbufvar(a:bufnr, '&softtabstop',
+                            \ g:EditorConfig_softtabstop_tab > 0 ?
+                            \ l:tabstop : g:EditorConfig_softtabstop_tab)
             endif
         else
             let l:indent_size = str2nr(a:config["indent_size"])
             if l:indent_size > 0
-                let &l:shiftwidth = l:indent_size
+                call setbufvar(a:bufnr, '&shiftwidth', l:indent_size)
                 if type(g:EditorConfig_softtabstop_space) != type([])
-                    let &l:softtabstop = g:EditorConfig_softtabstop_space > 0 ?
-                            \ &l:shiftwidth : g:EditorConfig_softtabstop_space
+                    call setbufvar(a:bufnr, '&softtabstop',
+                            \ g:EditorConfig_softtabstop_space > 0 ?
+                            \ l:indent_size : g:EditorConfig_softtabstop_space)
                 endif
             endif
         endif
 
     endif
 
     if s:IsRuleActive('end_of_line', a:config) &&
-                \ &l:modifiable
+                \ getbufvar(a:bufnr, '&modifiable')
         if a:config["end_of_line"] == "lf"
-            setl fileformat=unix
+            call setbufvar(a:bufnr, '&fileformat', 'unix')
         elseif a:config["end_of_line"] == "crlf"
-            setl fileformat=dos
+            call setbufvar(a:bufnr, '&fileformat', 'dos')
         elseif a:config["end_of_line"] == "cr"
-            setl fileformat=mac
+            call setbufvar(a:bufnr, '&fileformat', 'mac')
         endif
     endif
 
     if s:IsRuleActive('charset', a:config) &&
-                \ &l:modifiable
+                \ getbufvar(a:bufnr, '&modifiable')
         if a:config["charset"] == "utf-8"
-            setl fileencoding=utf-8
-            setl nobomb
+            call setbufvar(a:bufnr, '&fileencoding', 'utf-8')
+            call setbufvar(a:bufnr, '&bomb', 0)
         elseif a:config["charset"] == "utf-8-bom"
-            setl fileencoding=utf-8
-            setl bomb
+            call setbufvar(a:bufnr, '&fileencoding', 'utf-8')
+            call setbufvar(a:bufnr, '&bomb', 1)
         elseif a:config["charset"] == "latin1"
-            setl fileencoding=latin1
-            setl nobomb
+            call setbufvar(a:bufnr, '&fileencoding', 'latin1')
+            call setbufvar(a:bufnr, '&bomb', 0)
         elseif a:config["charset"] == "utf-16be"
-            setl fileencoding=utf-16be
-            setl bomb
+            call setbufvar(a:bufnr, '&fileencoding', 'utf-16be')
+            call setbufvar(a:bufnr, '&bomb', 1)
         elseif a:config["charset"] == "utf-16le"
-            setl fileencoding=utf-16le
-            setl bomb
+            call setbufvar(a:bufnr, '&fileencoding', 'utf-16le')
+            call setbufvar(a:bufnr, '&bomb', 1)
         endif
     endif
 
     augroup editorconfig_trim_trailing_whitespace
         autocmd! BufWritePre <buffer>
         if s:IsRuleActive('trim_trailing_whitespace', a:config) &&
                     \ get(a:config, 'trim_trailing_whitespace', 'false') ==# 'true'
-            autocmd BufWritePre <buffer> call s:TrimTrailingWhitespace()
+            execute 'autocmd BufWritePre <buffer=' . a:bufnr . '> call s:TrimTrailingWhitespace()'
         endif
     augroup END
 
     if s:IsRuleActive('insert_final_newline', a:config)
         if exists('+fixendofline')
             if a:config["insert_final_newline"] == "false"
-                setl nofixendofline
+                call setbufvar(a:bufnr, '&fixendofline', 0)
             else
-                setl fixendofline
+                call setbufvar(a:bufnr, '&fixendofline', 1)
             endif
         elseif  exists(':SetNoEOL') == 2
             if a:config["insert_final_newline"] == "false"
@@ -490,23 +508,39 @@ function! s:ApplyConfig(config) abort " Set the buffer options {{{1
         let l:max_line_length = str2nr(a:config['max_line_length'])
 
         if l:max_line_length >= 0
-            let &l:textwidth = l:max_line_length
+            call setbufvar(a:bufnr, '&textwidth', l:max_line_length)
             if g:EditorConfig_preserve_formatoptions == 0
-                setlocal formatoptions+=tc
+                " setlocal formatoptions+=tc
+                let l:fo = getbufvar(a:bufnr, '&formatoptions')
+                if l:fo !~# 't'
+                    let l:fo .= 't'
+                endif
+                if l:fo !~# 'c'
+                    let l:fo .= 'c'
+                endif
+                call setbufvar(a:bufnr, '&formatoptions', l:fo)
             endif
         endif
 
         if exists('+colorcolumn')
             if l:max_line_length > 0
                 if g:EditorConfig_max_line_indicator == 'line'
-                    setlocal colorcolumn+=+1
+                    " setlocal colorcolumn+=+1
+                    let l:cocol = getbufvar(a:bufnr, '&colorcolumn')
+                    if !empty(l:cocol)
+                        let l:cocol .= ','
+                    endif
+                    let l:cocol .= '+1'
+                    call setbufvar(a:bufnr, '&colorcolumn', l:cocol)
                 elseif g:EditorConfig_max_line_indicator == 'fill' &&
-                            \ l:max_line_length < &l:columns
+                            \ l:max_line_length < getbufvar(a:bufnr, '&columns')
                     " Fill only if the columns of screen is large enough
-                    let &l:colorcolumn = join(
-                                \ range(l:max_line_length+1,&l:columns),',')
+                    call setbufvar(a:bufnr, '&colorcolumn',
+                            \ join(range(l:max_line_length+1,
+                            \           getbufvar(a:bufnr, '&columns')),
+                            \       ','))
                 elseif g:EditorConfig_max_line_indicator == 'exceeding'
-                    let &l:colorcolumn = ''
+                    call setbufvar(a:bufnr, '&colorcolumn', '')
                     for l:match in getmatches()
                         if get(l:match, 'group', '') == 'ColorColumn'
                             call matchdelete(get(l:match, 'id'))
@@ -534,7 +568,8 @@ endfunction
 " }}}1
 
 function! s:TrimTrailingWhitespace() " {{{1
-    if &l:modifiable
+    " Called from within a buffer-specific autocmd, so we can use '%'
+    if getbufvar('%', '&modifiable')
         " don't lose user position when trimming trailing whitespace
         let s:view = winsaveview()
         try