me/-resolve-root-error does not work with :enum

[tomasd]

This snippet always fails in 0.6.2:

(-> [:map
     [:a [:enum "a" "b"]]]
    (m/explain {:a nil})
    (me/humanize {:resolve me/-resolve-root-error}))
Execution error (ExceptionInfo) at malli.core/-fail! (core.cljc:119).
:malli.core/invalid-schema {:schema "a"}

It works with -resolve-direct-error:

(-> [:map
     [:a [:enum "a" "b"]]]
    (m/explain {:a nil})
    (me/humanize ))
=> {:a ["should be either a or b"]}

[tomasd]

The problem is in this line https://github.com/metosin/malli/blob/master/src/malli/error.cljc#L247 :

(error-message {:schema (mu/get-in schema p)} options)

when evaluating errors from above

{:schema [:map [:a [:enum "a" "b"]]],
 :value {:a nil},
 :errors (#Error{:path [:a 0], :in [:a], :schema [:enum "a" "b"]})}

using path [:a 0] gives this result:

(mu/get-in [:map [:a [:enum "a" "b"]]] [:a 0])
=> "a"

(error-message {:schema (mu/get-in schema p)} options) => (error-message {:schema "a"} options)

I was able to fix it in the mu/get-in handling :enum's path explicitly:

(defn get-in
  "Like [[clojure.core/get-in]], but for LensSchemas."
  ([?schema ks]
   (get-in ?schema ks nil nil))
  ([?schema ks default]
   (get-in ?schema ks default nil))
  ([?schema [k & ks] default options]
   (let [schema (m/schema (or ?schema :map) options)]
     (cond
       (not k)
       schema

       ;; handle enum [0] path
       (= (m/type schema) :enum)
       schema

       :else
       (let [sentinel #?(:clj (Object.), :cljs (js-obj))
             schema (get schema k sentinel)]
         (cond
           (identical? schema sentinel) default
           ks (get-in schema ks default)
           :else schema))))))

But I'm not sure if this is the right way. If so I can provide a PR.

[ikitommi]

the correct fix might be to ask if the retuned value is m/-schema? and only then try to pull error out of it. So all code inside the me/-resolve-root-error. PR most welcome.

[ikitommi]

fixed in master