vim-patch:9.0.2031: TextChangedI may be triggered by non-insert mode change (#25656)

Problem:  `TextChangedI` can trigger on entering Insert mode if there
          was previously a change not in Insert mode.
Solution: Make it trigger only when text is actually changed in Insert
          mode.

closes: vim/vim#13265
closes: vim/vim#13338

https://github.com/vim/vim/commit/d7ae263af8f6a2da55ce3702d18c53ab1418bca7

Co-authored-by: Evgeni Chasnovski <evgeni.chasnovski@gmail.com>

3 files changed, 40 insertions, 14 deletions

diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index 4593748c25..a7a98b9557 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -143,6 +143,9 @@ static void insert_enter(InsertState *s)
   update_Insstart_orig = true;
 
   ins_compl_clear();        // clear stuff for CTRL-X mode
+  // Reset Changedtick_i, so that TextChangedI will only be triggered for stuff
+  // from insert mode
+  curbuf->b_last_changedtick_i = buf_get_changedtick(curbuf);
 
   // Trigger InsertEnter autocommands.  Do not do this for "r<CR>" or "grx".
   if (s->cmdchar != 'r' && s->cmdchar != 'v') {
@@ -356,6 +359,7 @@ static void insert_enter(InsertState *s)
     ins_apply_autocmds(EVENT_INSERTLEAVE);
   }
   did_cursorhold = false;
+  curbuf->b_last_changedtick = buf_get_changedtick(curbuf);
 }
 
 static int insert_check(VimState *state)
diff --git a/test/functional/autocmd/textchanged_spec.lua b/test/functional/autocmd/textchanged_spec.lua
index ffeb76835d..b90a0fd020 100644
--- a/test/functional/autocmd/textchanged_spec.lua
+++ b/test/functional/autocmd/textchanged_spec.lua
@@ -25,14 +25,15 @@ it('TextChangedI and TextChangedP autocommands', function()
   feed('o')
   poke_eventloop()
   feed('<esc>')
-  eq('I', eval('g:autocmd'))
+  -- TextChangedI triggers only if text is actually changed in Insert mode
+  eq('', eval('g:autocmd'))
 
   command([[let g:autocmd = '']])
   feed('S')
   poke_eventloop()
   feed('f')
   poke_eventloop()
-  eq('II', eval('g:autocmd'))
+  eq('I', eval('g:autocmd'))
   feed('<esc>')
 
   command([[let g:autocmd = '']])
@@ -42,7 +43,7 @@ it('TextChangedI and TextChangedP autocommands', function()
   poke_eventloop()
   feed('<C-N>')
   poke_eventloop()
-  eq('IIP', eval('g:autocmd'))
+  eq('IP', eval('g:autocmd'))
   feed('<esc>')
 
   command([[let g:autocmd = '']])
@@ -54,7 +55,7 @@ it('TextChangedI and TextChangedP autocommands', function()
   poke_eventloop()
   feed('<C-N>')
   poke_eventloop()
-  eq('IIPP', eval('g:autocmd'))
+  eq('IPP', eval('g:autocmd'))
   feed('<esc>')
 
   command([[let g:autocmd = '']])
@@ -68,7 +69,7 @@ it('TextChangedI and TextChangedP autocommands', function()
   poke_eventloop()
   feed('<C-N>')
   poke_eventloop()
-  eq('IIPPP', eval('g:autocmd'))
+  eq('IPPP', eval('g:autocmd'))
   feed('<esc>')
 
   command([[let g:autocmd = '']])
@@ -83,7 +84,7 @@ it('TextChangedI and TextChangedP autocommands', function()
   feed('<C-N>')
   poke_eventloop()
   feed('<C-N>')
-  eq('IIPPPP', eval('g:autocmd'))
+  eq('IPPPP', eval('g:autocmd'))
   feed('<esc>')
 
   eq({'foo', 'bar', 'foobar', 'foo'}, eval('getline(1, "$")'))
@@ -117,7 +118,7 @@ it('TextChangedI with setline()', function()
 end)
 
 -- oldtest: Test_Changed_ChangedI()
-it('TextChanged is triggerd after TextChangedI', function()
+it('TextChangedI and TextChanged', function()
   exec([[
     let [g:autocmd_i, g:autocmd_n] = ['','']
 
@@ -141,10 +142,20 @@ it('TextChanged is triggerd after TextChangedI', function()
   feed('o')
   poke_eventloop()
   feed('<esc>')
-  eq('N5', eval('g:autocmd_n'))
+  eq('', eval('g:autocmd_n'))
   eq('I5', eval('g:autocmd_i'))
 
   command([[call feedkeys("yyp", 'tnix')]])
   eq('N6', eval('g:autocmd_n'))
   eq('I5', eval('g:autocmd_i'))
+
+  -- TextChangedI should only trigger if change was done in Insert mode
+  command([[let g:autocmd_i = '']])
+  command([[call feedkeys("yypi\<esc>", 'tnix')]])
+  eq('', eval('g:autocmd_i'))
+
+  -- TextChanged should only trigger if change was done in Normal mode
+  command([[let g:autocmd_n = '']])
+  command([[call feedkeys("ibar\<esc>", 'tnix')]])
+  eq('', eval('g:autocmd_n'))
 end)
diff --git a/test/old/testdir/test_autocmd.vim b/test/old/testdir/test_autocmd.vim
index d80c505d80..447a716331 100644
--- a/test/old/testdir/test_autocmd.vim
+++ b/test/old/testdir/test_autocmd.vim
@@ -2476,27 +2476,28 @@ func Test_ChangedP()
   call cursor(3, 1)
   let g:autocmd = ''
   call feedkeys("o\<esc>", 'tnix')
-  call assert_equal('I', g:autocmd)
+  " `TextChangedI` triggers only if text is actually changed in Insert mode
+  call assert_equal('', g:autocmd)
 
   let g:autocmd = ''
   call feedkeys("Sf", 'tnix')
-  call assert_equal('II', g:autocmd)
+  call assert_equal('I', g:autocmd)
 
   let g:autocmd = ''
   call feedkeys("Sf\<C-N>", 'tnix')
-  call assert_equal('IIP', g:autocmd)
+  call assert_equal('IP', g:autocmd)
 
   let g:autocmd = ''
   call feedkeys("Sf\<C-N>\<C-N>", 'tnix')
-  call assert_equal('IIPP', g:autocmd)
+  call assert_equal('IPP', g:autocmd)
 
   let g:autocmd = ''
   call feedkeys("Sf\<C-N>\<C-N>\<C-N>", 'tnix')
-  call assert_equal('IIPPP', g:autocmd)
+  call assert_equal('IPPP', g:autocmd)
 
   let g:autocmd = ''
   call feedkeys("Sf\<C-N>\<C-N>\<C-N>\<C-N>", 'tnix')
-  call assert_equal('IIPPPP', g:autocmd)
+  call assert_equal('IPPPP', g:autocmd)
 
   call assert_equal(['foo', 'bar', 'foobar', 'foo'], getline(1, '$'))
   " TODO: how should it handle completeopt=noinsert,noselect?
@@ -3478,6 +3479,16 @@ func Test_Changed_ChangedI()
   " call assert_equal('N4', g:autocmd_n)
   call assert_equal('I3', g:autocmd_i)
 
+  " TextChangedI should only trigger if change was done in Insert mode
+  let g:autocmd_i = ''
+  call feedkeys("yypi\<esc>", 'tnix')
+  call assert_equal('', g:autocmd_i)
+
+  " TextChanged should only trigger if change was done in Normal mode
+  let g:autocmd_n = ''
+  call feedkeys("ibar\<esc>", 'tnix')
+  call assert_equal('', g:autocmd_n)
+
   " CleanUp
   call test_override("char_avail", 0)
   au! TextChanged  <buffer>