Fix #112 (#116)

camsaul · Sep 8, 2022 · 6361ebe · 6361ebe
1 parent fd7a1a0
commit 6361ebe
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Showing 3 changed files with 37 additions and 10 deletions.
diff --git a/src/methodical/impl/multifn/standard.clj b/src/methodical/impl/multifn/standard.clj
@@ -79,8 +79,8 @@
   (let [dispatch-values (transduce
                          (comp cat
                                (map meta)
-                               (map :dispatch-value)
-                               (filter some?))
+                               (filter #(contains? % :dispatch-value))
+                               (map :dispatch-value))
                          conj
                          []
                          (cons primary-methods (vals aux-methods)))]

diff --git a/src/methodical/interface.clj b/src/methodical/interface.clj
@@ -39,18 +39,18 @@
   (aux-methods [method-table]
     "Get a `qualifier -> dispatch-value -> [fn]` map of all auxiliary methods associated with this method table.")
 
-  (add-primary-method [method-table dispatch-value f]
+  (add-primary-method ^methodical.interface.MethodTable [method-table dispatch-value f]
     "Set the primary method implementation for `dispatch-value`, replacing it if it already exists.")
 
-  (remove-primary-method [method-table dispatch-value]
+  (remove-primary-method ^methodical.interface.MethodTable [method-table dispatch-value]
     "Remove the primary method for `dispatch-value`.")
 
-  (add-aux-method [method-table qualifier dispatch-value f]
+  (add-aux-method ^methodical.interface.MethodTable [method-table qualifier dispatch-value f]
     "Add an auxiliary method implementation for `qualifer` (e.g. `:before`) and `dispatch-value`. Unlike primary
     methods, auxiliary methods are not limited to one method per dispatch value; thus this method does not remove
     existing methods for this dispatch value. existing ")
 
-  (remove-aux-method [method-table qualifier dispatch-val method]
+  (remove-aux-method ^methodical.interface.MethodTable [method-table qualifier dispatch-val method]
     "Remove an auxiliary method from a method table. Because multiple auxiliary methods are allowed for the same
     dispatch value, existing implementations of `MethodTable` are currently only able to remove exact matches -- for
     functions, this usually means identical objects.

diff --git a/test/methodical/impl/multifn/standard_test.clj b/test/methodical/impl/multifn/standard_test.clj
@@ -1,8 +1,11 @@
 (ns methodical.impl.multifn.standard-test
-  (:require [clojure.math.combinatorics :as combo]
-            [clojure.test :as t]
-            [methodical.core :as m]
-            [methodical.impl.multifn.standard :as standard]))
+  (:require
+   [clojure.math.combinatorics :as combo]
+   [clojure.test :as t]
+   [methodical.core :as m]
+   [methodical.impl.multifn.standard :as standard]))
+
+(set! *warn-on-reflection* true)
 
 (derive ::parrot ::bird)
 (derive ::parakeet ::parrot)
@@ -205,3 +208,27 @@
                                       :default
                                       [expected-1 expected-2])}
                    (meta (standard/standard-effective-method combo dispatcher method-table dv)))))))))
+
+(t/deftest nil-dispatch-values-test
+  (t/testing "Dispatch values for `nil` should be calculated correctly (#112)"
+    (doseq [order [[nil :default]
+                   [:default nil]]]
+      (t/testing (str "\norder = " (pr-str order))
+        (let [mf* (atom nil)
+              mf  (-> (m/multifn
+                       (m/standard-multifn-impl
+                        (m/thread-last-method-combination)
+                        (m/multi-default-dispatcher identity)
+                        (m/standard-method-table)))
+                      (m/add-primary-method :default (fn [_next-method _m] :default))
+                      (m/add-primary-method nil (fn [_next-method _m]
+                                                  (@mf* :default)
+                                                  nil)))]
+          (reset! mf* mf)
+          (doseq [x order]
+            (t/testing (str \newline (pr-str x))
+              (t/testing (str \newline `m/effective-dispatch-value)
+                (t/is (= x
+                         (m/effective-dispatch-value mf x))))
+              (t/is (= x
+                       (mf x))))))))))