patch 7.4.1586
Problem:    Nesting partials doesn't work.
Solution:   Append arguments. (Ken Takata)
diff --git a/src/testdir/test_partial.vim b/src/testdir/test_partial.vim
index 21ad737..71d1837 100644
--- a/src/testdir/test_partial.vim
+++ b/src/testdir/test_partial.vim
@@ -20,9 +20,17 @@
   call Cb("zzz")
   call assert_equal("foo/bar/xxx", Cb("xxx"))
   call assert_equal("foo/bar/yyy", call(Cb, ["yyy"]))
+  let Cb2 = function(Cb)
+  call assert_equal("foo/bar/zzz", Cb2("zzz"))
+  let Cb3 = function(Cb, ["www"])
+  call assert_equal("foo/bar/www", Cb3())
 
   let Cb = function('MyFunc', [])
   call assert_equal("a/b/c", Cb("a", "b", "c"))
+  let Cb2 = function(Cb, [])
+  call assert_equal("a/b/d", Cb2("a", "b", "d"))
+  let Cb3 = function(Cb, ["a", "b"])
+  call assert_equal("a/b/e", Cb3("e"))
 
   let Sort = function('MySort', [1])
   call assert_equal([1, 2, 3], sort([3, 1, 2], Sort))