patch 9.1.0420: :browse oldfiles prompts even with single entry

Problem:  :browse oldfiles prompts even with single entry
Solution: Do not prompt, but edit the file directly,
          also when using :filter /pat/ browse oldfiles

closes: #14794

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index 2a5d842..5c34e86 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -5622,6 +5622,9 @@
     listitem_T	*li;
     int		nr = 0;
     char_u	*fname;
+    // for a single filtered match, remember the number
+    // so we can jump directly to it without prompting
+    int		matches = -1;
 
     if (l == NULL)
     {
@@ -5637,6 +5640,10 @@
 	fname = tv_get_string(&li->li_tv);
 	if (!message_filtered(fname))
 	{
+	    if (matches < 0)
+		matches = nr;
+	    else
+		matches = 0;
 	    msg_outnum((long)nr);
 	    msg_puts(": ");
 	    msg_outtrans(fname);
@@ -5654,7 +5661,15 @@
     if (cmdmod.cmod_flags & CMOD_BROWSE)
     {
 	quit_more = FALSE;
-	nr = prompt_for_number(FALSE);
+	// we only need to prompt if there is more than 1 match
+	if (matches > 0)
+	{
+	    nr = matches;
+	    // msg_putchar above sets needs_wait_return
+	    need_wait_return = FALSE;
+	}
+	else
+	    nr = prompt_for_number(FALSE);
 	msg_starthere();
 	if (nr > 0)
 	{
diff --git a/src/testdir/test_viminfo.vim b/src/testdir/test_viminfo.vim
index 1f4a72d..7aab271 100644
--- a/src/testdir/test_viminfo.vim
+++ b/src/testdir/test_viminfo.vim
@@ -1299,4 +1299,34 @@
   bw!
 endfunc
 
+func Test_viminfo_oldfiles_filter()
+  let v:oldfiles = []
+  let _viminfofile = &viminfofile
+  let &viminfofile=''
+  let lines = [
+	\ '# comment line',
+	\ '*encoding=utf-8',
+	\ "> /tmp/vimrc_one.vim",
+	\ "\t\"\t11\t0",
+	\ "",
+	\ "> /tmp/foobar.txt",
+	\ "\t\"\t11\t0",
+	\ "",
+	\ ]
+  call writefile(lines, 'Xviminfo1', 'D')
+  rviminfo! Xviminfo1
+  new
+  " filter returns a single item
+  let a = execute('filter /vim/ oldfiles')->split('\n')
+  call assert_equal(1, len(a))
+  " filter returns more than a single match
+  let a = execute('filter #tmp# oldfiles')->split('\n')
+  call assert_equal(2, len(a))
+  " don't get prompted for the file, but directly open it
+  filter /vim/ browse oldfiles
+  call assert_equal("/tmp/vimrc_one.vim", expand("%"))
+  bw
+  let &viminfofile = _viminfofile
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index 34f474d..aafbddc 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    420,
+/**/
     419,
 /**/
     418,