From a98970219ddc90b6f599203f6bb24da79fc6bbeb Mon Sep 17 00:00:00 2001
From: zeertzjq <zeertzjq@outlook.com>
Date: Thu, 24 Nov 2022 19:05:53 +0800
Subject: [PATCH] vim-patch:8.2.4062: match highlighting of tab too short

Problem:    Match highlighting of tab too short.
Solution:   Do not stop match highlighting if on a Tab. (Christian Brabandt,
            closes vim/vim#9507, closes vim/vim#9500)

https://github.com/vim/vim/commit/0bbca540f7377889e2154aa5731f6eeffcb5c0cc

Co-authored-by: Bram Moolenaar <Bram@vim.org>
---
 src/nvim/drawline.c                   |  5 +++--
 src/nvim/testdir/test_match.vim       | 18 ++++++++++++++++++
 test/functional/legacy/match_spec.lua | 26 ++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/src/nvim/drawline.c b/src/nvim/drawline.c
index b926f2da83..f0637549f7 100644
--- a/src/nvim/drawline.c
+++ b/src/nvim/drawline.c
@@ -1844,9 +1844,10 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
               n_extra = 0;
             }
           }
-          if (on_last_col) {
+          if (on_last_col && c != TAB) {
             // Do not continue search/match highlighting over the
-            // line break.
+            // line break, but for TABs the highlighting should
+            // include the complete width of the character
             search_attr = 0;
           }
 
diff --git a/src/nvim/testdir/test_match.vim b/src/nvim/testdir/test_match.vim
index 3c63314253..600b6132a9 100644
--- a/src/nvim/testdir/test_match.vim
+++ b/src/nvim/testdir/test_match.vim
@@ -421,4 +421,22 @@ func Test_matchdelete_redraw()
   bw!
 endfunc
 
+func Test_match_tab_with_linebreak()
+  CheckRunVimInTerminal
+
+  let lines =<< trim END
+    set linebreak
+    call setline(1, "\tix")
+    call matchadd('ErrorMsg', '\t')
+  END
+  call writefile(lines, 'XscriptMatchTabLinebreak')
+  let buf = RunVimInTerminal('-S XscriptMatchTabLinebreak', #{rows: 10})
+  call TermWait(buf)
+  call VerifyScreenDump(buf, 'Test_match_tab_linebreak', {})
+
+  call StopVimInTerminal(buf)
+  call delete('XscriptMatchTabLinebreak')
+endfunc
+
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/test/functional/legacy/match_spec.lua b/test/functional/legacy/match_spec.lua
index 51cd60864e..b6e45c396c 100644
--- a/test/functional/legacy/match_spec.lua
+++ b/test/functional/legacy/match_spec.lua
@@ -97,4 +97,30 @@ describe('match highlighting', function()
       :s/0^                                                                       |
     ]])
   end)
+
+  it('on a Tab vim-patch:8.2.4062', function()
+    local screen = Screen.new(75, 10)
+    screen:set_default_attr_ids({
+      [0] = {bold = true, foreground = Screen.colors.Blue},  -- NonText
+      [1] = {background = Screen.colors.Red, foreground = Screen.colors.White},  -- ErrorMsg
+    })
+    screen:attach()
+    exec([[
+      set linebreak
+      call setline(1, "\tix")
+      call matchadd('ErrorMsg', '\t')
+    ]])
+    screen:expect([[
+      {1:       ^ }ix                                                                 |
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+      {0:~                                                                          }|
+                                                                                 |
+    ]])
+  end)
 end)