diff --git a/test/test_heuristics.rb b/test/test_heuristics.rb
index 64e0f05b8..1f96cbf11 100755
--- a/test/test_heuristics.rb
+++ b/test/test_heuristics.rb
@@ -261,8 +261,8 @@ def test_asc_by_heuristics
   def test_asm_by_heuristics
     assert_heuristics({
       "Motorola 68K Assembly" => all_fixtures("Motorola 68K Assembly", "*.asm"),
-      # Assembly lacks a heuristic
-      nil => all_fixtures("Assembly", "*.asm")
+      "Assembly" => all_fixtures("Assembly", "*.asm"),
+      "Unix Assembly" => all_fixtures("Unix Assembly", "*.asm")
     })
   end
 
@@ -929,8 +929,8 @@ def test_rs_by_heuristics
   def test_s_by_heuristics
     assert_heuristics({
       "Motorola 68K Assembly" => all_fixtures("Motorola 68K Assembly", "*.s"),
-      # Unix Assembly lacks a heuristic
-      nil => all_fixtures("Unix Assembly", "*.s")
+      "Assembly" => all_fixtures("Assembly", "*.s"),
+      "Unix Assembly" => all_fixtures("Unix Assembly", "*.s")
     })
   end