replace deep-merge with meta-merge

project.clj

@@ -11,6 +11,8 @@
           :source-uri "https://github.com/metosin/reitit/{version}/{filepath}#L{line}"
           :metadata {:doc/format :markdown}}
 
+  :dependencies [[meta-merge "1.0.0"]]
+
   :profiles {:dev {:plugins [[jonase/eastwood "0.2.3"]
                              [lein-tach "0.3.0"]
                              [lein-doo "0.1.7"]

src/reitit/core.cljc

@@ -1,18 +1,5 @@
-(ns reitit.core)
-
-(defn- deep-merge [& values]
-  (let [[values strategy] (if (keyword? (first values))
-                            [(rest values) (first values)]
-                            [values :replace])]
-    (cond
-      (every? map? values)
-      (apply merge-with (partial deep-merge strategy) values)
-
-      (and (= strategy :into) (every? coll? values))
-      (reduce into values)
-
-      :else
-      (last values))))
+(ns reitit.core
+  (:require [meta-merge.core :refer [meta-merge]]))
 
 (defprotocol ExpandArgs
   (expand [this]))
@@ -54,16 +41,11 @@
 (defn map-meta [f routes]
   (mapv #(update % 1 f) routes))
 
-(defn merge-meta [key-strategy x]
+(defn merge-meta [x]
   (reduce
     (fn [acc [k v]]
-      (let [strategy (or (key-strategy k) :replace)]
-        (deep-merge strategy acc {k v})))
-    {}
-    x))
+      (meta-merge acc {k v}))
+    {} x))
 
-(defn resolve-routes
-  ([x]
-   (resolve-routes (constantly :replace) x))
-  ([key-strategy x]
-   (->> x (walk) (map-meta (partial merge-meta key-strategy)))))
+(defn resolve-routes [x]
+  (->> x (walk) (map-meta merge-meta)))

test/cljc/reitit/core_test.cljc

@@ -20,11 +20,11 @@
                    ["/:sub-id" {:parameters {:sub-id String}}]]
                   ["/pong"]
                   ["/admin" {:mw [:admin] :roles #{:admin}}
-                   ["/user" {:roles #{:user}}]
+                   ["/user" {:roles ^:replace #{:user}}]
                    ["/db" {:mw [:db]}]]]
           expected [["/api/ping" {:mw [:api], :handler :kikka}]
                     ["/api/user/:id/:sub-id" {:mw [:api], :parameters {:id String, :sub-id String}}]
                     ["/api/pong" {:mw [:api]}]
                     ["/api/admin/user" {:mw [:api :admin], :roles #{:user}}]
                     ["/api/admin/db" {:mw [:api :admin :db], :roles #{:admin}}]]]
-      (is (= expected (reitit/resolve-routes {:mw :into} routes))))))
+      (is (= expected (reitit/resolve-routes routes))))))