diff --git a/test/runtests.jl b/test/runtests.jl
index fd344cb..b2c9335 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -65,6 +65,36 @@ using Test
             @test node_depth(rulenode, RuleNode(100)) == 0
         end
 
+        @testset "rulesoftype" begin
+            #=    1
+               2  3  4
+                    5  6
+                   7    9
+                          10
+            =#
+            rulenode = RuleNode(
+                1,
+                [
+                    RuleNode(2),
+                    RuleNode(3),
+                    RuleNode(
+                        4,
+                        [
+                            RuleNode(5, [RuleNode(7)]),
+                            RuleNode(6, [RuleNode(9, [RuleNode(10)])])
+                        ]
+                    )
+                ]
+            )
+            @test isempty(rulesoftype(rulenode, Set((11, 12))))
+            ruleset = Set((1, 3, 7, 9, 10, 15, 23))
+            expected = Set((1, 3, 7, 9, 10))
+            @test rulesoftype(rulenode, ruleset) == expected
+            @test rulesoftype(rulenode, Set(1)) == Set(1)
+            @test isempty(rulesoftype(rulenode, Set{Int}()))
+            @test rulesoftype(RuleNode(1), Set((1, 2))) == Set(1)
+        end
+
         @testset "rule sequence" begin
 
             #=    1