patch 9.0.0506: line number argument for :badd does not work

Problem:    Line number argument for :badd does not work.
Solution:   Set the last cursor position in the new buffer. (closes #11161)

src/ex_cmds.c

@@ -2651,8 +2651,13 @@ do_ecmd(
 		// with the current window.
 		newbuf = buflist_new(ffname, sfname, tlnum,
 						    BLN_LISTED | BLN_NOCURWIN);
-		if (newbuf != NULL && (flags & ECMD_ALTBUF))
+		if (newbuf != NULL)
-		    curwin->w_alt_fnum = newbuf->b_fnum;
+		{
+		    if (flags & ECMD_ALTBUF)
+			curwin->w_alt_fnum = newbuf->b_fnum;
+		    if (tlnum > 0)
+			newbuf->b_last_cursor.lnum = tlnum;
+		}
 		goto theend;
 	    }
 	    buf = buflist_new(ffname, sfname, 0L,

src/testdir/test_buffer.vim

@@ -361,6 +361,13 @@ func Test_badd_options()
   close
   close
   bwipe! SomeNewBuffer
+
+  badd +3 XbaddFile
+  call writefile(range(6), 'XbaddFile', 'D')
+  buf XbaddFile
+  call assert_equal([0, 3, 1, 0], getpos('.'))
+
+  bwipe! XbaddFile
 endfunc
 
 func Test_balt()

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    506,
 /**/
     505,
 /**/