vim-patch:9.0.0884: mouse shape remains in op-pending mode after failed change (#21066)

Problem:    Mouse shape remains in op-pending mode after failed change.
Solution:   Reset finish_op and restore it. (closes vim/vim#11545)

cdeb65729d

src/nvim/ops.c

@@ -2483,8 +2483,14 @@ int op_change(oparg_T *oap)
     fix_indent();
   }
 
+  // Reset finish_op now, don't want it set inside edit().
+  const bool save_finish_op = finish_op;
+  finish_op = false;
+
   retval = edit(NUL, false, (linenr_T)1);
 
+  finish_op = save_finish_op;
+
   // In Visual block mode, handle copying the new text to all lines of the
   // block.
   // Don't repeat the insert when Insert mode ended with CTRL-C.
@@ -5635,8 +5641,6 @@ bool set_ref_in_opfunc(int copyID)
 static void op_function(const oparg_T *oap)
   FUNC_ATTR_NONNULL_ALL
 {
-  const TriState save_virtual_op = virtual_op;
-  const bool save_finish_op = finish_op;
   const pos_T orig_start = curbuf->b_op_start;
   const pos_T orig_end = curbuf->b_op_end;
 
@@ -5663,9 +5667,11 @@ static void op_function(const oparg_T *oap)
 
     // Reset virtual_op so that 'virtualedit' can be changed in the
     // function.
+    const TriState save_virtual_op = virtual_op;
     virtual_op = kNone;
 
     // Reset finish_op so that mode() returns the right value.
+    const bool save_finish_op = finish_op;
     finish_op = false;
 
     typval_T rettv;
@@ -6205,8 +6211,6 @@ void do_pending_operator(cmdarg_T *cap, int old_col, bool gui_yank)
         // Restore linebreak, so that when the user edits it looks as before.
         restore_lbr(lbr_saved);
 
-        // Reset finish_op now, don't want it set inside edit().
-        finish_op = false;
         if (op_change(oap)) {           // will call edit()
           cap->retval |= CA_COMMAND_BUSY;
         }

src/nvim/testdir/test_normal.vim

@@ -3713,4 +3713,37 @@ func Test_normal_count_out_of_range()
   bwipe!
 endfunc
 
+" Test that mouse shape is restored to Normal mode after failed "c" operation.
+func Test_mouse_shape_after_failed_change()
+  CheckFeature mouseshape
+  CheckCanRunGui
+
+  let lines =<< trim END
+    set mouseshape+=o:busy
+    setlocal nomodifiable
+    let g:mouse_shapes = []
+
+    func SaveMouseShape(timer)
+      let g:mouse_shapes += [getmouseshape()]
+    endfunc
+
+    func SaveAndQuit(timer)
+      call writefile(g:mouse_shapes, 'Xmouseshapes')
+      quit
+    endfunc
+
+    call timer_start(50, {_ -> feedkeys('c')})
+    call timer_start(100, 'SaveMouseShape')
+    call timer_start(150, {_ -> feedkeys('c')})
+    call timer_start(200, 'SaveMouseShape')
+    call timer_start(250, 'SaveAndQuit')
+  END
+  call writefile(lines, 'Xmouseshape.vim', 'D')
+  call RunVim([], [], "-g -S Xmouseshape.vim")
+  sleep 300m
+  call assert_equal(['busy', 'arrow'], readfile('Xmouseshapes'))
+
+  call delete('Xmouseshapes')
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

test/functional/ui/mode_spec.lua

@@ -17,6 +17,7 @@ describe('ui mode_change event', function()
       [1] = {bold=true, reverse=true},
       [2] = {bold=true},
       [3] = {reverse=true},
+      [4] = {background=Screen.colors.Red, foreground=Screen.colors.White},  -- ErrorMsg
     })
   end)
 
@@ -43,6 +44,25 @@ describe('ui mode_change event', function()
       {0:~                        }|
                                |
     ]], mode="normal"}
+
+    screen:try_resize(50, 4)
+    command('set nomodifiable')
+
+    feed('c')
+    screen:expect{grid=[[
+      ^                                                  |
+      {0:~                                                 }|
+      {0:~                                                 }|
+                                                        |
+    ]], mode="operator"}
+
+    feed('c')
+    screen:expect{grid=[[
+      ^                                                  |
+      {0:~                                                 }|
+      {0:~                                                 }|
+      {4:E21: Cannot make changes, 'modifiable' is off}     |
+    ]], mode="normal"}
   end)
 
   it('works in insert mode', function()