Consider following example. I have a map with some structure, some properties are simp

Interesting. All schemas run both :decode and <code c

Documenting to myself, current order on decode: <div class="highlight highlight-so

Problematic execution order of decode/encode about malli HOT 2 OPEN

solita-nikoa commented on May 28, 2024

Problematic execution order of decode/encode

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Comments (2)

ikitommi commented on May 28, 2024

Interesting. All schemas run both :decode and :encode in children in same order. I also think this is wrong. I need to revisit the ordering, thanks for reporting.

Tested with a dirty (and invalid) fix:

diff --git a/src/malli/core.cljc b/src/malli/core.cljc
index d66b3f9..a2b3b1e 100644
--- a/src/malli/core.cljc
+++ b/src/malli/core.cljc
@@ -519,7 +519,8 @@
 (defn -parent-children-transformer [parent children transformer method options]
   (let [parent-transformer (-value-transformer transformer parent method options)
         child-transformers (into [] (keep #(-transformer % transformer method options)) children)
-        child-transformer (when (seq child-transformers) (apply -comp (rseq child-transformers)))]
+        mapper (if (= :encode method) identity rseq)
+        child-transformer (when (seq child-transformers) (apply -comp (mapper child-transformers)))]
     (-intercepting parent-transformer child-transformer)))

.. which gives "correct" order/results for this case but doesn't solve the whole problem.

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ikitommi commented on May 28, 2024

Documenting to myself, current order on decode:

(let [log (atom [])
      log! (fn [s p] (fn [x] (swap! log conj [(:i (m/properties s)) p]) x))]
  (m/decode
   [:map {:i 0}
    [:x {:i 1} [:int {:i 2}]]
    [:y {:i 3} [:string {:i 4}]]
    [:z {:i 5} [:maybe {:i 6} [:and {:i 7}
                               [:keyword {:i 8}]
                               [:or {:i 9}
                                [:string {:i 10}]
                                [:qualified-keyword {:i 11}]]]]]]
   {:x 1
    :y "kikka"
    :z :kikka/kukka}
   (mt/transformer
    {:default-decoder {:compile (fn [schema _]
                                  {:enter (log! schema :enter)
                                   :leave (log! schema :leave)})}}))
  @log)
;[[0 :enter]
; [1 :enter]
; [2 :enter]
; [2 :leave]
; [1 :leave]
; [3 :enter]
; [4 :enter]
; [4 :leave]
; [3 :leave]
; [5 :enter]
; [6 :enter]
; [7 :enter]
; [8 :enter]
; [8 :leave]
; [9 :enter]
; [10 :enter]
; [10 :leave]
; [11 :enter]
; [11 :leave]
; [9 :leave]
; [7 :leave]
; [6 :leave]
; [5 :leave]
; [0 :leave]]