diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index 936a2d0..f675697 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -2150,6 +2150,10 @@
   eval mydict.len->call([], mydict)->assert_equal(4)
   call assert_fails("call call('Mylen', [], 0)", 'E715:')
   call assert_fails('call foo', 'E107:')
+
+  " This once caused a crash.
+  call call(test_null_function(), [])
+  call call(test_null_partial(), [])
 endfunc
 
 func Test_char2nr()
diff --git a/src/testdir/test_listdict.vim b/src/testdir/test_listdict.vim
index 1b0796d..601dd17 100644
--- a/src/testdir/test_listdict.vim
+++ b/src/testdir/test_listdict.vim
@@ -743,6 +743,7 @@
 
   " should not crash
   call assert_fails('echo reduce([1], test_null_function())', 'E1132:')
+  call assert_fails('echo reduce([1], test_null_partial())', 'E1132:')
 endfunc
 
 " splitting a string to a List using split()