vim-patch:8.1.1189: mode is not cleared when leaving Insert mode

Problem:    Mode is not cleared when leaving Insert mode.
Solution:   Clear the mode when got_int is set. (Ozaki Kiichi, closes vim/vim#4270)
abc7c7fc5a

src/nvim/edit.c

@@ -4251,7 +4251,7 @@ static bool ins_esc(long *count, int cmdchar, bool nomove)
   // Otherwise remove the mode message.
   if (reg_recording != 0 || restart_edit != NUL) {
     showmode();
-  } else if (p_smd && !skip_showmode()) {
+  } else if (p_smd && (got_int || !skip_showmode())) {
     msg("");
   }
   // Exit Insert mode

src/nvim/testdir/test_bufline.vim

@@ -19,7 +19,7 @@ func Test_setbufline_getbufline()
   let b = bufnr('%')
   wincmd w
   call assert_equal(1, setbufline(b, 5, ['x']))
-  call assert_equal(1, setbufline(1234, 1, ['x']))
+  call assert_equal(1, setbufline(bufnr('$') + 1, 1, ['x']))
   call assert_equal(0, setbufline(b, 4, ['d', 'e']))
   call assert_equal(['c'], b->getbufline(3))
   call assert_equal(['d'], getbufline(b, 4))

src/nvim/testdir/test_messages.vim

@@ -95,6 +95,37 @@ func Test_echoerr()
   call test_ignore_error('RESET')
 endfunc
 
+func Test_mode_message_at_leaving_insert_by_ctrl_c()
+  if !has('terminal') || has('gui_running')
+    return
+  endif
+
+  " Set custom statusline built by user-defined function.
+  let testfile = 'Xtest.vim'
+  call writefile([
+        \ 'func StatusLine() abort',
+        \ '  return ""',
+        \ 'endfunc',
+        \ 'set statusline=%!StatusLine()',
+        \ 'set laststatus=2',
+        \ ], testfile)
+
+  let rows = 10
+  let buf = term_start([GetVimProg(), '--clean', '-S', testfile], {'term_rows': rows})
+  call term_wait(buf, 200)
+  call assert_equal('run', job_status(term_getjob(buf)))
+
+  call term_sendkeys(buf, "i")
+  call WaitForAssert({-> assert_match('^-- INSERT --\s*$', term_getline(buf, rows))})
+  call term_sendkeys(buf, "\<C-C>")
+  call WaitForAssert({-> assert_match('^\s*$', term_getline(buf, rows))})
+
+  call term_sendkeys(buf, ":qall!\<CR>")
+  call WaitForAssert({-> assert_equal('dead', job_status(term_getjob(buf)))})
+  exe buf . 'bwipe!'
+  call delete(testfile)
+endfunc
+
 func Test_echospace()
   set noruler noshowcmd laststatus=1
   call assert_equal(&columns - 1, v:echospace)

test/functional/legacy/messages_spec.lua

@@ -337,6 +337,47 @@ describe('messages', function()
     end)
   end)
 
+  describe('mode is cleared when', function()
+    before_each(function()
+      screen = Screen.new(40, 6)
+      screen:set_default_attr_ids({
+        [1] = {bold = true, foreground = Screen.colors.Blue},  -- NonText
+        [2] = {bold = true},  -- ModeMsg
+        [3] = {bold = true, reverse=true},  -- StatusLine
+      })
+      screen:attach()
+    end)
+
+    -- oldtest: Test_mode_message_at_leaving_insert_by_ctrl_c()
+    it('leaving Insert mode with Ctrl-C vim-patch:8.1.1189', function()
+      exec([[
+        func StatusLine() abort
+          return ""
+        endfunc
+        set statusline=%!StatusLine()
+        set laststatus=2
+      ]])
+      feed('i')
+      screen:expect([[
+        ^                                        |
+        {1:~                                       }|
+        {1:~                                       }|
+        {1:~                                       }|
+        {3:                                        }|
+        {2:-- INSERT --}                            |
+      ]])
+      feed('<C-C>')
+      screen:expect([[
+        ^                                        |
+        {1:~                                       }|
+        {1:~                                       }|
+        {1:~                                       }|
+        {3:                                        }|
+                                                |
+      ]])
+    end)
+  end)
+
   -- oldtest: Test_ask_yesno()
   it('y/n prompt works', function()
     screen = Screen.new(75, 6)