patch 7.4.1723

Problem:    When using try/catch in 'tabline' it is still considered an
            error and the tabline will be disabled.
Solution:   Check did_emsg instead of called_emsg. (haya14busa, closes #746)

src/screen.c

@@ -10266,16 +10266,16 @@ draw_tabline(void)
     /* Use the 'tabline' option if it's set. */
     if (*p_tal != NUL)
     {
-	int	save_called_emsg = called_emsg;
+	int	saved_did_emsg = did_emsg;
 
 	/* Check for an error.  If there is one we would loop in redrawing the
 	 * screen.  Avoid that by making 'tabline' empty. */
-	called_emsg = FALSE;
+	did_emsg = FALSE;
 	win_redr_custom(NULL, FALSE);
-	if (called_emsg)
+	if (did_emsg)
 	    set_string_option_direct((char_u *)"tabline", -1,
 					   (char_u *)"", OPT_FREE, SID_ERROR);
-	called_emsg |= save_called_emsg;
+	did_emsg |= saved_did_emsg;
     }
     else
 #endif

src/testdir/test_alot.vim

@@ -24,6 +24,7 @@ source test_set.vim
 source test_sort.vim
 source test_statusline.vim
 source test_syn_attr.vim
+source test_tabline.vim
 source test_timers.vim
 source test_undolevels.vim
 source test_unlet.vim

src/testdir/test_tabline.vim

@@ -0,0 +1,43 @@
+function! TablineWithCaughtError()
+  let s:func_in_tabline_called = 1
+  try
+    call eval('unknown expression')
+  catch
+  endtry
+  return ''
+endfunction
+
+function! TablineWithError()
+  let s:func_in_tabline_called = 1
+  call eval('unknown expression')
+  return ''
+endfunction
+
+function! Test_caught_error_in_tabline()
+  let showtabline_save = &showtabline
+  set showtabline=2
+  let s:func_in_tabline_called = 0
+  let tabline = '%{TablineWithCaughtError()}'
+  let &tabline = tabline
+  redraw!
+  call assert_true(s:func_in_tabline_called)
+  call assert_equal(tabline, &tabline)
+  set tabline=
+  let &showtabline = showtabline_save
+endfunction
+
+function! Test_tabline_will_be_disabled_with_error()
+  let showtabline_save = &showtabline
+  set showtabline=2
+  let s:func_in_tabline_called = 0
+  let tabline = '%{TablineWithError()}'
+  try
+    let &tabline = tabline
+    redraw!
+  catch
+  endtry
+  call assert_true(s:func_in_tabline_called)
+  call assert_equal('', &tabline)
+  set tabline=
+  let &showtabline = showtabline_save
+endfunction

src/version.c

@@ -748,6 +748,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1723,
 /**/
     1722,
 /**/