Clojurians Log v2

(def Thing
    [:map 
     [:x :int]
     [:y :string]])

  (def Lookup
    [:map-of :int Thing])

  (def things (map #(array-map :x % :y (str %)) (range 10)))

  (malli.core/validate 
   Lookup
   (into {} (map (juxt :x identity)) things)) ;; true

  (def bad-things (map #(array-map :x %) (range 10)))

  (malli.core/validate 
   Lookup
   (into {} (map (juxt :x identity)) bad-things)) ;; false

  (malli.core/coerce
   Lookup
   (into {} (map (juxt :x identity)) bad-things)) ;; throws

  ;; So far so good, but

  (malli.core/coerce
   Lookup
   (into {} (map (juxt :x identity)) bad-things)
   malli.transform/strip-extra-keys-transformer
   ) ;; {} ??

strip-extra-keys-transformer should probably not touch map-of?

I think there have been some surprises related to this topic before as well

Hi Joel! Hope all is well

https://github.com/metosin/malli/issues/1118

hi, all good here 🙂

so Tommi's slightly cryptic message in that issue is that this is the current behaviour, but we should probably have something else...

you might be able to dissoc :map-of from strip-extra-keys-transformer as a workaround

🙂 yeah I got that. dropping the encoders/decoders for map-of will solve my use case, so I think I'll just inline that

what was your expectation? strip-extra-keys not doing anything to :map-of ?

yes

I'll write that down in the issue, it's a good data point

the point being that they are not removed if the val schema validates

(malli.core/coerce
   Lookup
   (into {} (map (juxt :x identity)) things)
   mt/strip-extra-keys-transformer) ;;{0 {:x 0 ...

yes

so strip-extra-keys-transformer is really strip-key-value-pairs-that-don't-match-schema

that name would indeed have been clearer 😄

and that's not quite the right name: for :map it only looks at keys, for :map-of it looks at key-value-pairs

I guess that's actually the root of the surprise here

agree