1 files changed, 22 insertions, 0 deletions
diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeInfosTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeInfosTests.java
new file mode 100644
index 00000000..3a84923d
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeInfosTests.java
@@ -0,0 +1,22 @@
+package org.shedlang.compiler.typechecker;
+
+import org.junit.jupiter.api.Test;
+import org.shedlang.compiler.types.Types;
+
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.equalTo;
+import static org.zwobble.precisely.Matchers.isSequence;
+
+public class TypeInfosTests {
+    @Test
+    public void supertypesOfTypeIncludeThatTypeAndTop() {
+        var typeInfos = TypeInfos.EMPTY;
+
+        var supertypes = typeInfos.supertypes(Types.INT);
+
+        assertThat(supertypes, isSequence(
+            equalTo(Types.INT),
+            equalTo(Types.TOP)
+        ));
+    }
+}