diff --git a/src/func/tests.rs b/src/func/tests.rs
index 94ec8e7..14f7e18 100644
--- a/src/func/tests.rs
+++ b/src/func/tests.rs
@@ -417,3 +417,29 @@ pub fn select_of_equal_is_same<
         fa0(),
     )
 }
+
+#[test]
+fn eqr_ok() {
+    eqr("test", 0, 0).unwrap();
+}
+
+#[test]
+#[should_panic(expected = "test: 1 != 2")]
+fn eqr_panic() {
+    eqr("test", 1, 2).unwrap();
+}
+
+#[test]
+#[should_panic]
+fn eqr_err_add() {
+    (R::default() + eqr("test", 1, 2) + eqr("test", 3, 4)).unwrap();
+}
+
+#[test]
+#[should_panic]
+fn eqr_err_add_assign() {
+    let mut r = R::default();
+    r += eqr("test", 1, 2);
+    r += eqr("test", 3, 4);
+    r.unwrap();
+}