One approach to fixing lazy parsing of registries via from-ast

src/malli/core.cljc

@@ -2568,10 +2568,12 @@
      (map? ?ast) (if-let [s (-lookup (:type ?ast) options)]
                    (let [r (when-let [r (:registry ?ast)] (-delayed-registry r from-ast))
                          options (cond-> options r (-update :registry #(mr/composite-registry r (or % (-registry options)))))
-                         ast (cond-> ?ast r (-update :properties #(assoc % :registry (-property-registry r options identity))))]
-                     (cond (and (into-schema? s) (-ast? s)) (-from-ast s ast options)
-                           (into-schema? s) (-into-schema s (:properties ast) (-vmap #(from-ast % options) (:children ast)) options)
-                           :else s))
+                         ast (cond-> ?ast r (-update :properties #(assoc % :registry r)))]
+                     (if (into-schema? s)
+                       (if (-ast? s)
+                         (-from-ast s ast options)
+                         (-into-schema s (:properties ast) (-vmap #(from-ast % options) (:children ast)) options))
+                       s))
                    (-fail! ::invalid-ast {:ast ?ast}))
      :else (-fail! ::invalid-ast {:ast ?ast}))))
 

test/malli/core_test.cljc

@@ -3581,3 +3581,27 @@
   (is (not (m/validate [:sequential {:min 11} :int] (eduction identity (range 10)))))
   (is (not (m/validate [:seqable {:min 11} :int] (eduction identity (range 10)))))
   (is (nil? (m/explain [:sequential {:min 9} :int] (eduction identity (range 10))))))
+
+(deftest from-ast-delayed-registry-test
+  (let [form [:int {:registry {::foo :int}}]
+        forced? (volatile! false)
+        original-delayed-registry m/-delayed-registry
+        ;;TODO refactor by providing custom IntoSchema constructor
+        s (with-redefs [m/-delayed-registry
+                        (fn [m f]
+                          (-> (original-delayed-registry m f)
+                              (update-vals (fn [v]
+                                             (reify m/IntoSchema
+                                               (m/-into-schema [_ properties children options]
+                                                 (vreset! forced? true)
+                                                 (m/-into-schema v properties children options)))))))]
+            (m/from-ast (m/ast form)))
+        _ (is (not @forced?))
+        form' (m/form s)
+        _ (is @forced?)]
+    (is (= form form'))))
+
+(comment
+  (m/from-ast (m/ast [:int {:registry {::foo :int}}]))
+  (m/form (m/from-ast (m/ast [:int {:registry {::foo :int}}])))
+)