vim-patch:8.2.4724: current instance of last search pattern not easily spotted

Problem:    Current instance of last search pattern not easily spotted.
Solution:   Add CurSearch highlighting. (closes vim/vim#10133)
a43993897a

This fixes CurSearch highlight for multiline match.
Omit screen redrawing code because Nvim redraws CurSearch differently.

src/nvim/buffer_defs.h

@@ -1018,6 +1018,7 @@ typedef struct {
                         // match (may continue in next line)
   buf_T *buf;     // the buffer to search for a match
   linenr_T lnum;        // the line to search for a match
+  linenr_T lines;       // number of lines starting from lnum
   int attr;             // attributes to be used for a match
   int attr_cur;         // attributes currently active in win_line()
   linenr_T first_lnum;  // first lnum to search for multi-line pat

src/nvim/match.c

@@ -582,6 +582,7 @@ bool prepare_search_hl_line(win_T *wp, linenr_T lnum, colnr_T mincol, char_u **l
     }
     shl->startcol = MAXCOL;
     shl->endcol = MAXCOL;
+    shl->lines = 0;
     shl->attr_cur = 0;
     shl->is_addpos = false;
     if (cur != NULL) {
@@ -606,6 +607,11 @@ bool prepare_search_hl_line(win_T *wp, linenr_T lnum, colnr_T mincol, char_u **l
       } else {
         shl->endcol = MAXCOL;
       }
+      if (shl->rm.endpos[0].lnum != shl->rm.startpos[0].lnum) {
+        shl->lines = shl->rm.endpos[0].lnum - shl->rm.startpos[0].lnum;
+      } else {
+        shl->lines = 1;
+      }
       // Highlight one character for an empty match.
       if (shl->startcol == shl->endcol) {
         if ((*line)[shl->endcol] != NUL) {
@@ -668,10 +674,12 @@ int update_search_hl(win_T *wp, linenr_T lnum, colnr_T col, char_u **line, match
         if (shl->endcol < next_col) {
           shl->endcol = next_col;
         }
-        // Use "CurSearch" highlight for current search match
+        // Highlight the match were the cursor is using the CurSearch
+        // group.
         if (shl == search_hl
             && (HL_ATTR(HLF_LC) || wp->w_hl_ids[HLF_LC])
             && wp->w_cursor.lnum == lnum
+            && wp->w_cursor.lnum < shl->lnum + shl->lines
             && wp->w_cursor.col >= shl->startcol
             && wp->w_cursor.col < shl->endcol) {
           shl->attr_cur = win_hl_attr(wp, HLF_LC) ? win_hl_attr(wp, HLF_LC) : HL_ATTR(HLF_LC);

src/nvim/option.c

@@ -262,8 +262,8 @@ typedef struct vimoption {
 
 #define HIGHLIGHT_INIT \
   "8:SpecialKey,~:EndOfBuffer,z:TermCursor,Z:TermCursorNC,@:NonText,d:Directory,e:ErrorMsg," \
-  "i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,a:LineNrAbove,b:LineNrBelow,N:CursorLineNr," \
+  "i:IncSearch,l:Search,y:CurSearch,m:MoreMsg,M:ModeMsg,n:LineNr,a:LineNrAbove,b:LineNrBelow," \
-  "G:CursorLineSign,O:CursorLineFold" \
+  "N:CursorLineNr,G:CursorLineSign,O:CursorLineFold" \
   "r:Question,s:StatusLine,S:StatusLineNC,c:VertSplit,t:Title,v:Visual,V:VisualNOS,w:WarningMsg," \
   "W:WildMenu,f:Folded,F:FoldColumn,A:DiffAdd,C:DiffChange,D:DiffDelete,T:DiffText,>:SignColumn," \
   "-:Conceal,B:SpellBad,P:SpellCap,R:SpellRare,L:SpellLocal,+:Pmenu,=:PmenuSel,x:PmenuSbar," \

src/nvim/testdir/test_search.vim

@@ -946,6 +946,34 @@ func Test_incsearch_substitute()
   call Incsearch_cleanup()
 endfunc
 
+func Test_hlsearch_cursearch()
+  CheckScreendump
+
+  let lines =<< trim END
+    set hlsearch scrolloff=0
+    call setline(1, ['one', 'foo', 'bar', 'baz', 'foo', 'bar'])
+    hi Search ctermbg=yellow
+    hi CurSearch ctermbg=blue
+  END
+  call writefile(lines, 'Xhlsearch_cursearch')
+  let buf = RunVimInTerminal('-S Xhlsearch_cursearch', {'rows': 9, 'cols': 60})
+
+  call term_sendkeys(buf, "gg/foo\<CR>")
+  call VerifyScreenDump(buf, 'Test_hlsearch_cursearch_single_line_1', {})
+
+  call term_sendkeys(buf, "n")
+  call VerifyScreenDump(buf, 'Test_hlsearch_cursearch_single_line_2', {})
+
+  call term_sendkeys(buf, "?\<CR>")
+  call VerifyScreenDump(buf, 'Test_hlsearch_cursearch_single_line_3', {})
+
+  call term_sendkeys(buf, "gg/foo\\nbar\<CR>")
+  call VerifyScreenDump(buf, 'Test_hlsearch_cursearch_multiple_line', {})
+
+  call StopVimInTerminal(buf)
+  call delete('Xhlsearch_cursearch')
+endfunc
+
 " Similar to Test_incsearch_substitute() but with a screendump halfway.
 func Test_incsearch_substitute_dump()
   CheckOption incsearch

test/functional/ui/searchhl_spec.lua

@@ -109,54 +109,108 @@ describe('search highlighting', function()
     ]])
   end)
 
-  it('works for match under cursor', function()
+  describe('CurSearch highlight', function()
-    screen:set_default_attr_ids({
+    before_each(function()
-        [1] = {background = Screen.colors.Yellow},
+      screen:set_default_attr_ids({
-        [2] = {foreground = Screen.colors.Gray100, background = Screen.colors.Gray0},
+        [1] = {background = Screen.colors.Yellow},  -- Search
-        [3] = {foreground = Screen.colors.Red},
+        [2] = {foreground = Screen.colors.White, background = Screen.colors.Black},  -- CurSearch
-    })
+        [3] = {foreground = Screen.colors.Red},  -- WarningMsg
+      })
+      command('highlight CurSearch guibg=Black guifg=White')
+    end)
 
-    command('highlight CurSearch guibg=Black guifg=White')
+    it('works for match under cursor', function()
-    insert([[
+      insert([[
-      There is no way that a bee should be
+        There is no way that a bee should be
-      able to fly. Its wings are too small
+        able to fly. Its wings are too small
-      to get its fat little body off the
+        to get its fat little body off the
-      ground. The bee, of course, flies
+        ground. The bee, of course, flies
-      anyway because bees don't care what
+        anyway because bees don't care what
-      humans think is impossible.]])
+        humans think is impossible.]])
 
-    feed('/bee<CR>')
+      feed('/bee<CR>')
-    screen:expect{grid=[[
+      screen:expect{grid=[[
-      There is no way that a {2:^bee} should be    |
+        There is no way that a {2:^bee} should be    |
-      able to fly. Its wings are too small    |
+        able to fly. Its wings are too small    |
-      to get its fat little body off the      |
+        to get its fat little body off the      |
-      ground. The {1:bee}, of course, flies       |
+        ground. The {1:bee}, of course, flies       |
-      anyway because {1:bee}s don't care what     |
+        anyway because {1:bee}s don't care what     |
-      humans think is impossible.             |
+        humans think is impossible.             |
-      {3:search hit BOTTOM, continuing at TOP}    |
+        {3:search hit BOTTOM, continuing at TOP}    |
-    ]]}
+      ]]}
 
-    feed('nn')
+      feed('nn')
-    screen:expect{grid=[[
+      screen:expect{grid=[[
-      There is no way that a {1:bee} should be    |
+        There is no way that a {1:bee} should be    |
-      able to fly. Its wings are too small    |
+        able to fly. Its wings are too small    |
-      to get its fat little body off the      |
+        to get its fat little body off the      |
-      ground. The {1:bee}, of course, flies       |
+        ground. The {1:bee}, of course, flies       |
-      anyway because {2:^bee}s don't care what     |
+        anyway because {2:^bee}s don't care what     |
-      humans think is impossible.             |
+        humans think is impossible.             |
-      /bee                                    |
+        /bee                                    |
-    ]]}
+      ]]}
 
-    feed('N')
+      feed('N')
-    screen:expect{grid=[[
+      screen:expect{grid=[[
-      There is no way that a {1:bee} should be    |
+        There is no way that a {1:bee} should be    |
-      able to fly. Its wings are too small    |
+        able to fly. Its wings are too small    |
-      to get its fat little body off the      |
+        to get its fat little body off the      |
-      ground. The {2:^bee}, of course, flies       |
+        ground. The {2:^bee}, of course, flies       |
-      anyway because {1:bee}s don't care what     |
+        anyway because {1:bee}s don't care what     |
-      humans think is impossible.             |
+        humans think is impossible.             |
-      ?bee                                    |
+        ?bee                                    |
-    ]]}
+      ]]}
+    end)
+
+    it('works for multiline match', function()
+      insert([[
+        one
+        foo
+        bar
+        baz
+        foo
+        bar]])
+        feed('gg/foo<CR>')
+        screen:expect([[
+          one                                     |
+          {2:^foo}                                     |
+          bar                                     |
+          baz                                     |
+          {1:foo}                                     |
+          bar                                     |
+          /foo                                    |
+        ]])
+        feed('n')
+        screen:expect([[
+          one                                     |
+          {1:foo}                                     |
+          bar                                     |
+          baz                                     |
+          {2:^foo}                                     |
+          bar                                     |
+          /foo                                    |
+        ]])
+        feed('?<CR>')
+        screen:expect([[
+          one                                     |
+          {2:^foo}                                     |
+          bar                                     |
+          baz                                     |
+          {1:foo}                                     |
+          bar                                     |
+          ?foo                                    |
+        ]])
+        feed('gg/foo\\nbar<CR>')
+        screen:expect([[
+          one                                     |
+          {2:^foo}                                     |
+          {1:bar}                                     |
+          baz                                     |
+          {1:foo}                                     |
+          {1:bar}                                     |
+          /foo\nbar                               |
+        ]])
+    end)
   end)
 
   it('highlights after EOL', function()