diff --git a/crates/h10/src/decl_info/tests.rs b/crates/h10/src/decl_info/tests.rs
index e50fc7f..5de941b 100644
--- a/crates/h10/src/decl_info/tests.rs
+++ b/crates/h10/src/decl_info/tests.rs
@@ -3,7 +3,7 @@ use crate::ast::TopDecl;
 use crate::parser::parse_module;
 
 #[test]
-fn id() {
+fn simple_value() {
     let pgm = "id x = x";
     let mut decl_infos = program_decl_infos(pgm);
     assert_eq!(decl_infos.len(), 1);
@@ -25,6 +25,61 @@ fn id() {
     assert_eq!(to_sorted_vec(&used_values), empty_id_vec());
 }
 
+#[test]
+fn simple_type() {
+    let pgm = "data X = A | B";
+    let mut decl_infos = program_decl_infos(pgm);
+    assert_eq!(decl_infos.len(), 1);
+
+    let DeclInfo {
+        defines: Defs {
+            tys: def_tys,
+            values: def_values,
+        },
+        uses: Uses {
+            tys: used_tys,
+            values: used_values,
+        },
+    } = decl_infos.remove(0);
+
+    assert_eq!(to_sorted_vec(&def_tys), vec!["X"]);
+    assert_eq!(to_sorted_vec(&def_values), vec!["A", "B"]);
+    assert_eq!(to_sorted_vec(&used_tys), empty_id_vec());
+    assert_eq!(to_sorted_vec(&used_values), empty_id_vec());
+}
+
+#[test]
+fn simple_pattern() {
+    #[rustfmt::skip]
+    let lines = [
+        "f (a : b) = 1 + f b",
+        "f [] = 0",
+    ];
+    let pgm = lines.join("\n");
+    let mut decl_infos = program_decl_infos(&pgm);
+    assert_eq!(decl_infos.len(), 2);
+
+    {
+        let DeclInfo {
+            defines:
+                Defs {
+                    tys: def_tys,
+                    values: def_values,
+                },
+            uses:
+                Uses {
+                    tys: used_tys,
+                    values: used_values,
+                },
+        } = decl_infos.remove(0);
+
+        assert_eq!(to_sorted_vec(&def_tys), empty_id_vec());
+        assert_eq!(to_sorted_vec(&def_values), vec!["f"]);
+        assert_eq!(to_sorted_vec(&used_tys), empty_id_vec());
+        assert_eq!(to_sorted_vec(&used_values), vec!["+", ":"]);
+    }
+}
+
 fn to_sorted_vec(set: &Set<String>) -> Vec<&str> {
     let mut values: Vec<&str> = set.iter().map(|s| s.as_str()).collect();
     values.sort();