Merge pull request #37422 from zeertzjq/vim-9.1.0059

vim-patch:9.1.{0059,0117,0671,1043,partial:1110}: WinNewPre

runtime/doc/autocmd.txt

@@ -1232,6 +1232,20 @@ WinLeave			Before leaving a window.  If the window to be
 				WinLeave autocommands (but not for ":new").
 				Not used for ":qa" or ":q" when exiting Vim.
 				Before WinClosed.
+							*WinNewPre*
+WinNewPre			Before creating a new window.  Triggered
+				before commands that modify window layout by
+				creating a split.
+				Not done when creating tab pages and for the
+				first window, as the window structure is not
+				initialized yet and so is generally not safe.
+				It is not allowed to modify window layout
+				while executing commands for the WinNewPre
+				event.
+				Most useful to store current window layout
+				and compare it with the new layout after the
+				Window has been created.
+
 							*WinNew*
 WinNew				When a new window was created.  Not done for
 				the first window, when Vim has just started.

runtime/doc/options.txt

@@ -2580,7 +2580,8 @@ A jump table for the options with a short description can be found at |Q_op|.
 		|VimResized|,
 		|VimResume|,
 		|VimSuspend|,
-		|WinNew|
+		|WinNew|,
+		|WinNewPre|
 
 				*'expandtab'* *'et'* *'noexpandtab'* *'noet'*
 'expandtab' 'et'	boolean	(default off)

runtime/lua/vim/_meta/api_keysets.lua

@@ -218,6 +218,7 @@ error('Cannot require a meta file')
 --- |'WinEnter'
 --- |'WinLeave'
 --- |'WinNew'
+--- |'WinNewPre'
 --- |'WinResized'
 --- |'WinScrolled'
 

runtime/lua/vim/_meta/options.lua

@@ -2258,7 +2258,8 @@ vim.go.ei = vim.go.eventignore
 --- 	`VimResized`,
 --- 	`VimResume`,
 --- 	`VimSuspend`,
---- 	`WinNew`
+--- 	`WinNew`,
+--- 	`WinNewPre`
 ---
 --- @type string
 vim.o.eventignorewin = ""

src/nvim/auevents.lua

@@ -138,7 +138,8 @@ return {
     WinClosed = true, -- after closing a window
     WinEnter = true, -- after entering a window
     WinLeave = true, -- before leaving a window
-    WinNew = false, -- when entering a new window
+    WinNewPre = false, -- before creating a new window
+    WinNew = false, -- after creating a new window
     WinResized = true, -- after a window was resized
     WinScrolled = true, -- after a window was scrolled or resized
   },

src/nvim/window.c

@@ -1127,6 +1127,10 @@ win_T *win_split_ins(int size, int flags, win_T *new_wp, int dir, frame_T *to_fl
     return NULL;
   }
 
+  if (new_wp == NULL) {
+    trigger_winnewpre();
+  }
+
   win_T *oldwin;
   if (flags & WSP_TOP) {
     oldwin = firstwin;
@@ -3069,6 +3073,13 @@ int win_close(win_T *win, bool free_buf, bool force)
   return OK;
 }
 
+static void trigger_winnewpre(void)
+{
+  window_layout_lock();
+  apply_autocmds(EVENT_WINNEWPRE, NULL, NULL, false, NULL);
+  window_layout_unlock();
+}
+
 static void do_autocmd_winclosed(win_T *win)
   FUNC_ATTR_NONNULL_ALL
 {
@@ -4351,6 +4362,10 @@ void free_tabpage(tabpage_T *tp)
 ///
 /// It will edit the current buffer, like after :split.
 ///
+/// Does not trigger WinNewPre, since the window structures
+/// are not completely setup yet and could cause dereferencing
+/// NULL pointers
+///
 /// @param after Put new tabpage after tabpage "after", or after the current
 ///              tabpage in case of 0.
 /// @param filename Will be passed to apply_autocmds().

test/old/testdir/test_autocmd.vim

@@ -276,7 +276,9 @@ endfunc
 func Test_win_tab_autocmd()
   let g:record = []
 
+  defer CleanUpTestAuGroup()
   augroup testing
+    au WinNewPre * call add(g:record, 'WinNewPre')
     au WinNew * call add(g:record, 'WinNew')
     au WinClosed * call add(g:record, 'WinClosed')
     au WinEnter * call add(g:record, 'WinEnter')
@@ -293,7 +295,7 @@ func Test_win_tab_autocmd()
   close
 
   call assert_equal([
-	\ 'WinLeave', 'WinNew', 'WinEnter',
+	\ 'WinNewPre', 'WinLeave', 'WinNew', 'WinEnter',
 	\ 'WinLeave', 'TabLeave', 'WinNew', 'WinEnter', 'TabNew', 'TabEnter',
 	\ 'WinLeave', 'TabLeave', 'WinClosed', 'TabClosed', 'WinEnter', 'TabEnter',
 	\ 'WinLeave', 'WinClosed', 'WinEnter'
@@ -310,10 +312,81 @@ func Test_win_tab_autocmd()
 	\ 'WinClosed', 'TabClosed'
 	\ ], g:record)
 
+  let g:record = []
+  copen
+  help
+  tabnext
+  vnew
+
+  call assert_equal([
+	\ 'WinNewPre', 'WinLeave', 'WinNew', 'WinEnter',
+	\ 'WinNewPre', 'WinLeave', 'WinNew', 'WinEnter',
+	\ 'WinNewPre', 'WinLeave', 'WinNew', 'WinEnter'
+	\ ], g:record)
+
+  unlet g:record
+endfunc
+
+func Test_WinNewPre()
+  " Test that the old window layout can be accessed before a new window is created.
+  let g:layouts_pre = []
+  let g:layouts_post = []
+  augroup testing
+    au WinNewPre * call add(g:layouts_pre, winlayout())
+    au WinNew * call add(g:layouts_post, winlayout())
+  augroup END
+  defer CleanUpTestAuGroup()
+  split
+  call assert_notequal(g:layouts_pre[0], g:layouts_post[0])
+  split
+  call assert_equal(g:layouts_pre[1], g:layouts_post[0])
+  call assert_notequal(g:layouts_pre[1], g:layouts_post[1])
+  " not triggered for tabnew
+  tabnew
+  call assert_equal(2, len(g:layouts_pre))
+  unlet g:layouts_pre
+  unlet g:layouts_post
+
+  " Test modifying window layout during WinNewPre throws.
+  let g:caught = 0
   augroup testing
     au!
+    au WinNewPre * split
   augroup END
-  unlet g:record
+  try
+    vnew
+  catch
+    let g:caught += 1
+  endtry
+  augroup testing
+    au!
+    au WinNewPre * tabnew
+  augroup END
+  try
+    vnew
+  catch
+    let g:caught += 1
+  endtry
+  augroup testing
+    au!
+    au WinNewPre * close
+  augroup END
+  try
+    vnew
+  catch
+    let g:caught += 1
+  endtry
+  augroup testing
+    au!
+    au WinNewPre * tabclose
+  augroup END
+  try
+    vnew
+  catch
+    let g:caught += 1
+  endtry
+  call assert_equal(4, g:caught)
+  unlet g:caught
 endfunc
 
 func Test_WinResized()
@@ -2820,7 +2893,8 @@ endfunc
 
 func Test_autocmd_nested()
   let g:did_nested = 0
-  augroup Testing
+  defer CleanUpTestAuGroup()
+  augroup testing
     au WinNew * edit somefile
     au BufNew * let g:did_nested = 1
   augroup END
@@ -2830,7 +2904,7 @@ func Test_autocmd_nested()
   bwipe! somefile
 
   " old nested argument still works
-  augroup Testing
+  augroup testing
     au!
     au WinNew * nested edit somefile
     au BufNew * let g:did_nested = 1
@@ -4378,6 +4452,38 @@ func Test_BufEnter_botline()
   set hidden&vim
 endfunc
 
+" those commands caused null pointer access, see #15464
+func Test_WinNewPre_crash()
+  defer CleanUpTestAuGroup()
+  let _cmdheight=&cmdheight
+  augroup testing
+    au!
+    autocmd WinNewPre * redraw
+  augroup END
+  tabnew
+  tabclose
+  augroup testing
+    au!
+    autocmd WinNewPre * wincmd t
+  augroup END
+  tabnew
+  tabclose
+  augroup testing
+    au!
+    autocmd WinNewPre * wincmd b
+  augroup END
+  tabnew
+  tabclose
+  augroup testing
+    au!
+    autocmd WinNewPre * set cmdheight+=1
+  augroup END
+  tabnew
+  tabclose
+  let &cmdheight=_cmdheight
+endfunc
+
+
 " This was using freed memory
 func Test_autocmd_BufWinLeave_with_vsp()
   new

test/old/testdir/test_crash.vim

@@ -191,52 +191,49 @@ func Test_crash1_3()
   let buf = RunVimInTerminal('sh', #{cmd: 'sh'})
 
   let file = 'crash/poc_ex_substitute'
-  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'\<cr>"
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 150)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/poc_uaf_exec_instructions'
-  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'\<cr>"
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 150)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/poc_uaf_check_argument_types'
-  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'\<cr>"
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 150)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/double_free'
-  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'\<cr>"
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 50)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/dialog_changed_uaf'
-  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'\<cr>"
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 150)
+  call s:RunCommandAndWait(buf, args)
+
+  let file = 'crash/nullpointer'
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'"
+  let args = printf(cmn_args, vim, file)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/heap_overflow3'
   let cmn_args = "%s -u NONE -i NONE -n -X -m -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 150)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/heap_overflow_glob2regpat'
   let cmn_args = "%s -u NONE -i NONE -n -X -m -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 50)
+  call s:RunCommandAndWait(buf, args)
 
   let file = 'crash/nullptr_regexp_nfa'
   let cmn_args = "%s -u NONE -i NONE -n -X -m -n -e -s -S %s -c ':qa!'"
   let args = printf(cmn_args, vim, file)
-  call term_sendkeys(buf, args)
-  call TermWait(buf, 50)
+  call s:RunCommandAndWait(buf, args)
 
   " clean up
   exe buf .. "bw!"

test/old/testdir/test_window_cmd.vim

@@ -1043,8 +1043,7 @@ func Test_win_splitmove()
   let s:triggered = []
   augroup WinSplitMove
     au!
-    " Nvim: WinNewPre not ported yet. Also needs full port of v9.1.0117 to pass.
-    " au WinNewPre * let s:triggered += ['WinNewPre']
+    au WinNewPre * let s:triggered += ['WinNewPre']
     au WinNew * let s:triggered += ['WinNew', win_getid()]
     au WinClosed * let s:triggered += ['WinClosed', str2nr(expand('<afile>'))]
   augroup END