follow-up on CLJS-460 defmulti ignores optional :hierarchy argument

Author: zajac

src/main/cljs/cljs/core.cljs

@@ -9965,17 +9965,17 @@ reduces them without incurring seq initialization"
      false)))
 
 (defn- dominates
-  [x y prefer-table]
-  (or (prefers* x y prefer-table) (isa? x y)))
+  [x y prefer-table hierarchy]
+  (or (prefers* x y prefer-table) (isa? hierarchy x y)))
 
 (defn- find-and-cache-best-method
   [name dispatch-val hierarchy method-table prefer-table method-cache cached-hierarchy]
   (let [best-entry (reduce (fn [be [k _ :as e]]
                              (if (isa? @hierarchy dispatch-val k)
-                               (let [be2 (if (or (nil? be) (dominates k (first be) prefer-table))
+                               (let [be2 (if (or (nil? be) (dominates k (first be) prefer-table @hierarchy))
                                            e
                                            be)]
-                                 (when-not (dominates (first be2) k prefer-table)
+                                 (when-not (dominates (first be2) k prefer-table @hierarchy)
                                    (throw (js/Error.
                                            (str "Multiple methods in multimethod '" name
                                                 "' match dispatch value: " dispatch-val " -> " k

src/test/cljs/cljs/core_test.cljs

@@ -243,6 +243,14 @@
 (defmulti foo2' identity)
 (defmethod foo2' 0 [x] x)
 
+(def three-levels-h (-> (make-hierarchy)
+                        (derive :parent :gparent)
+                        (derive :child :parent)))
+
+(defmulti multi-with-h (fn [v] v) :hierarchy #'three-levels-h)
+(defmethod multi-with-h :gparent [_] :gparent)
+(defmethod multi-with-h :parent [_] :parent)
+
 (deftest test-multimethods-2
   (let [r (rect 4 13)
         c (circle 12)]
@@ -272,6 +280,7 @@
         (is (not (my-map? not-m))))
       ;; multimethod hashing
       (is (= foo2' (ffirst {foo2' 1})))
+      (is (= :parent (multi-with-h :child)))
 )))
 
 (deftest test-transducers