customqf enhancements

- restore initial lines / remove annotations
- wrap/tighten changing of local settings to where it is necessary
- add highlighting for neomakeBufferName (linking to qfFileName used by
  Vim itself since 8.0.1332 - not yet in Neovim)

Closes neomake#1857.

autoload/neomake/quickfix.vim

@@ -11,11 +11,17 @@ function! neomake#quickfix#enable() abort
         autocmd!
         autocmd FileType qf call neomake#quickfix#FormatQuickfix()
     augroup END
+    if &filetype ==# 'qf'
+        call neomake#quickfix#FormatQuickfix()
+    endif
 endfunction
 
 
 function! neomake#quickfix#disable() abort
     let s:is_enabled = 0
+    if &filetype ==# 'qf'
+        call neomake#quickfix#FormatQuickfix()
+    endif
 endfunction
 
 
@@ -56,13 +62,26 @@ function! neomake#quickfix#set_syntax(names) abort
     endfor
 endfunction
 
+function! s:set_qf_lines(lines) abort
+    let ul = &l:undolevels
+    setlocal modifiable nonumber undolevels=-1
+
+    call setline(1, a:lines)
+
+    let &l:undolevels = ul
+    setlocal nomodifiable nomodified
+endfunction
+
 function! s:clean_qf_annotations() abort
     if exists('b:_neomake_maker_match_id')
         silent! call matchdelete(b:_neomake_maker_match_id)
     endif
     if exists('b:_neomake_gutter_match_id')
         silent! call matchdelete(b:_neomake_gutter_match_id)
     endif
+    if exists('b:_neomake_bufname_match_id')
+        silent! call matchdelete(b:_neomake_bufname_match_id)
+    endif
     if exists('b:_neomake_cursor_match_id')
         silent! call matchdelete(b:_neomake_cursor_match_id)
     endif
@@ -74,10 +93,15 @@ function! neomake#quickfix#FormatQuickfix() abort
     if !s:is_enabled || &filetype !=# 'qf'
         if exists('b:neomake_qf')
             call neomake#signs#Clean(buf, 'file')
+            if exists('b:_neomake_qf_orig_lines')
+                call s:set_qf_lines(b:_neomake_qf_orig_lines)
+                unlet b:_neomake_qf_orig_lines
+            endif
             unlet! b:neomake_qf
             augroup neomake_qf
                 autocmd! * <buffer>
             augroup END
+            call s:clean_qf_annotations()
         endif
         return
     endif
@@ -104,9 +128,6 @@ function! neomake#quickfix#FormatQuickfix() abort
         let b:neomake_qf = 'project'
     endif
 
-    let ul = &l:undolevels
-    setlocal modifiable nonumber undolevels=-1
-
     let lines = []
     let signs = []
     let i = 0
@@ -214,9 +235,10 @@ function! neomake#quickfix#FormatQuickfix() abort
         endif
     endfor
 
-    call setline(1, lines)
-    let &l:undolevels = ul
-    setlocal nomodifiable nomodified
+    if !exists('b:_neomake_qf_orig_lines')
+        let b:_neomake_qf_orig_lines = getbufline('%', 1, '$')
+    endif
+    call s:set_qf_lines(lines)
 
     if exists('+breakindent')
         " Keeps the text aligned with the fake gutter.
@@ -242,6 +264,12 @@ function! neomake#quickfix#FormatQuickfix() abort
                     \ '\%>'.(maker_width).'c'
                     \ .'.*\%<'.(b:neomake_start_col + 2).'c',
                     \ s:match_base_priority+2)
+        if exists('b:_neomake_bufname_match_id')
+            silent! call matchdelete(b:_neomake_bufname_match_id)
+        endif
+        let b:_neomake_bufname_match_id = matchadd('neomakeBufferName',
+                    \ '.*\%<'.(maker_width + 1).'c',
+                    \ s:match_base_priority+3)
     endif
 
     augroup neomake_qf

syntax/neomake/qf.vim

@@ -5,3 +5,4 @@ let b:current_syntax = 'neomake_qf'
 highlight default link neomakeListNr LineNr
 highlight default link neomakeCursorListNr CursorLineNr
 highlight default link neomakeMakerName FoldColumn
+highlight default link neomakeBufferName qfFileName

tests/customqf.vader

@@ -361,3 +361,64 @@ Execute (custom qf gets disabled with manual setloclist()):
   finally
     call neomake#quickfix#disable()
   endtry
+
+Execute (disabling it restores initial lines (in qf window)):
+  new
+  call setloclist(0, [{
+      \ 'lnum': 1,
+      \ 'text': 'Text with marker nmcfg:{"name": "b", "short": "b"}',
+      \}])
+  lopen
+  AssertEqual getline(1), '|1| Text with marker nmcfg:{"name": "b", "short": "b"}'
+  call neomake#quickfix#enable()
+  try
+    AssertEqual getline(1), 'b 1:- Text with marker'
+    call neomake#quickfix#disable()
+    AssertEqual getline(1), '|1| Text with marker nmcfg:{"name": "b", "short": "b"}'
+    lclose
+    bwipe
+  finally
+    call neomake#quickfix#disable()
+  endtry
+
+Execute (enabling does not touch existing lists (in another window)):
+  new
+  call setloclist(0, [{
+      \ 'lnum': 1,
+      \ 'text': 'Text with marker nmcfg:{"name": "b", "short": "b"}',
+      \}])
+  lopen
+  AssertEqual getline(1), '|1| Text with marker nmcfg:{"name": "b", "short": "b"}'
+  wincmd p
+  call neomake#quickfix#enable()
+  try
+    wincmd p
+    AssertEqual getline(1), '|1| Text with marker nmcfg:{"name": "b", "short": "b"}'
+    call neomake#quickfix#disable()
+    AssertEqual getline(1), '|1| Text with marker nmcfg:{"name": "b", "short": "b"}'
+    lclose
+    bwipe
+  finally
+    call neomake#quickfix#disable()
+  endtry
+
+Execute (enabling does not touch existing lists (in another window)):
+  new
+  call setloclist(0, [{
+      \ 'lnum': 1,
+      \ 'text': 'Text with marker nmcfg:{"name": "b", "short": "b"}',
+      \}])
+  lopen
+  AssertEqual getline(1), '|1| Text with marker nmcfg:{"name": "b", "short": "b"}'
+  call neomake#quickfix#enable()
+  try
+    AssertEqual getline(1), 'b 1:- Text with marker'
+    wincmd p
+    call neomake#quickfix#disable()
+    wincmd p
+    AssertEqual getline(1), 'b 1:- Text with marker'
+    lclose
+    bwipe
+  finally
+    call neomake#quickfix#disable()
+  endtry