vim-patch:8.2.0413: buffer menu does not handle special buffers properly

Problem:    Buffer menu does not handle special buffers properly.
Solution:   Keep a dictionary with buffer names to reliably keep track of
            entries.
            Also trigger BufFilePre and BufFilePost for command-line and
            terminal buffers when the name changes.
5e94a29ebb

src/nvim/buffer.c

@@ -5639,7 +5639,9 @@ void wipe_buffer(buf_T *buf, bool aucmd)
 void buf_open_scratch(handle_T bufnr, char *bufname)
 {
   (void)do_ecmd((int)bufnr, NULL, NULL, NULL, ECMD_ONE, ECMD_HIDE, NULL);
+  apply_autocmds(EVENT_BUFFILEPRE, NULL, NULL, false, curbuf);
   (void)setfname(curbuf, bufname, NULL, true);
+  apply_autocmds(EVENT_BUFFILEPOST, NULL, NULL, false, curbuf);
   set_option_value("bh", 0L, "hide", OPT_LOCAL);
   set_option_value("bt", 0L, "nofile", OPT_LOCAL);
   set_option_value("swf", 0L, NULL, OPT_LOCAL);

src/nvim/eval/funcs.c

@@ -9914,7 +9914,11 @@ static void f_termopen(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   // at this point the buffer has no terminal instance associated yet, so unset
   // the 'swapfile' option to ensure no swap file will be created
   curbuf->b_p_swf = false;
+
+  apply_autocmds(EVENT_BUFFILEPRE, NULL, NULL, false, curbuf);
   (void)setfname(curbuf, (char *)NameBuff, NULL, true);
+  apply_autocmds(EVENT_BUFFILEPOST, NULL, NULL, false, curbuf);
+
   // Save the job id and pid in b:terminal_job_{id,pid}
   Error err = ERROR_INIT;
   // deprecated: use 'channel' buffer option

src/nvim/testdir/test_alot.vim

@@ -16,7 +16,6 @@ source test_ga.vim
 source test_glob2regpat.vim
 source test_global.vim
 source test_lispwords.vim
-source test_menu.vim
 source test_move.vim
 source test_put.vim
 source test_reltime.vim

src/nvim/testdir/test_menu.vim

@@ -19,6 +19,41 @@ func Test_load_menu()
   call assert_equal('', v:errmsg)
 endfunc
 
+func Test_buffer_menu_special_buffers()
+  " Load in runtime menus
+  try
+    source $VIMRUNTIME/menu.vim
+  catch
+    call assert_report('error while loading menus: ' . v:exception)
+  endtry
+
+  let v:errmsg = ''
+  doautocmd LoadBufferMenu VimEnter
+  call assert_equal('', v:errmsg)
+
+  let orig_buffer_menus = execute("nmenu Buffers")
+
+  " Make a new command-line window, test that it does not create a new buffer
+  " menu.
+  call feedkeys("q::let cmdline_buffer_menus=execute('nmenu Buffers')\<CR>:q\<CR>", 'ntx')
+  call assert_equal(len(split(orig_buffer_menus, "\n")), len(split(cmdline_buffer_menus, "\n")))
+  call assert_equal(orig_buffer_menus, execute("nmenu Buffers"))
+
+  if has('terminal')
+    " Open a terminal window and test that it does not create a buffer menu
+    " item.
+    terminal
+    let term_buffer_menus = execute('nmenu Buffers')
+    call assert_equal(len(split(orig_buffer_menus, "\n")), len(split(term_buffer_menus, "\n")))
+    bwipe!
+    call assert_equal(orig_buffer_menus, execute("nmenu Buffers"))
+  endif
+
+  " Remove menus to clean up
+  source $VIMRUNTIME/delmenu.vim
+  call assert_equal('', v:errmsg)
+endfunc
+
 func Test_translate_menu()
   if !has('multi_lang')
     return
@@ -121,6 +156,7 @@ endfunc
 " Test for menu item completion in command line
 func Test_menu_expand()
   " Create the menu itmes for test
+  menu Dummy.Nothing lll
   for i in range(1, 4)
     let m = 'menu Xmenu.A' .. i .. '.A' .. i
     for j in range(1, 4)
@@ -146,7 +182,7 @@ func Test_menu_expand()
   " Test for <Up> to go up a menu
   call feedkeys(":emenu Xmenu.A\<Tab>\<Down>\<Up>\<Up>\<Up>" ..
         \ "\<C-A>\<C-B>\"\<CR>", 'xt')
-  call assert_equal('"emenu Buffers. Xmenu.', @:)
+  call assert_equal('"emenu Dummy. Xmenu.', @:)
 
   " Test for expanding only submenus
   call feedkeys(":popup Xmenu.\<C-A>\<C-B>\"\<CR>", 'xt')
@@ -166,6 +202,7 @@ func Test_menu_expand()
 
   set wildmenu&
   unmenu Xmenu
+  unmenu Dummy
 
   " Test for expanding popup menus with some hidden items
   menu Xmenu.foo.A1 a1
@@ -175,7 +212,6 @@ func Test_menu_expand()
   call feedkeys(":popup Xmenu.\<C-A>\<C-B>\"\<CR>", 'xt')
   call assert_equal('"popup Xmenu.foo', @:)
   unmenu Xmenu
-
 endfunc
 
 " Test for the menu_info() function