add eq tests for non-equal tags

compiler/test_gen/src/gen_compare.rs

@@ -442,4 +442,67 @@ mod gen_compare {
         assert_evals_to!("[[1]] != [[1]]", false, bool);
         assert_evals_to!("[[2]] != [[1]]", true, bool);
     }
+
+    #[test]
+    fn compare_union_same_content() {
+        assert_evals_to!(
+            indoc!(
+                r#"
+            Foo : [ A I64, B I64 ]
+
+            a : Foo
+            a = A 42
+
+            b : Foo
+            b = B 42
+
+            a == b
+            "#
+            ),
+            false,
+            bool
+        );
+    }
+
+    #[test]
+    fn compare_recursive_union_same_content() {
+        assert_evals_to!(
+            indoc!(
+                r#"
+                Expr : [ Add Expr Expr, Mul Expr Expr, Val1 I64, Val2 I64 ]
+
+                v1 : Expr 
+                v1 = Val1 42
+
+                v2 : Expr 
+                v2 = Val2 42
+
+                v1 == v2
+            "#
+            ),
+            false,
+            bool
+        );
+    }
+
+    #[test]
+    fn compare_nullable_recursive_union_same_content() {
+        assert_evals_to!(
+            indoc!(
+                r#"
+                Expr : [ Add Expr Expr, Mul Expr Expr, Val1 I64, Val2 I64, Empty ]
+
+                v1 : Expr 
+                v1 = Val1 42
+
+                v2 : Expr 
+                v2 = Val2 42
+
+                v1 == v2
+            "#
+            ),
+            false,
+            bool
+        );
+    }
 }