Fulcro bug or edge case

fulcro-merge-bug-or-quirk.cljs

(defn get-case-ident
  [props]
  (let [case-id? string?]
    (cond
      (-> props :nexus.case.image-annotation/id merge/nilify-not-found case-id?) [:nexus.case.image-annotation/id (:nexus.case.image-annotation/id props)]
      (-> props :nexus.case.test-case/id merge/nilify-not-found case-id?) [:nexus.case.test-case/id (:nexus.case.test-case/id props)]
      :else (log/error "Cannot derive a valid ident. Invalid props." props))))

(defsc AddState [_ _]
  {:query [:nexus.case.image-annotation/id
           :cmmn.case/state]
   :ident :nexus.case.image-annotation/id})

(defsc ImageAnnotationCase [this props]
  {:query [:nexus.case.image-annotation/id
           :cmmn.case/name
           ;; cmmn.case/state -> not queried here but under :>/bla placeholder!
           {:>/bla (comp/get-query AddState)}]
   :ident :nexus.case.image-annotation/id})

(defsc TestCase [this props]
  {:query [:nexus.case.test-case/id
           :cmmn.case/name
           :cmmn.case/state]
   :ident :nexus.case.test-case/id})

(defsc CaseUnion
  "Union query component for different Case types."
  [this props computed]
  {:query (fn [] {:nexus.case.test-case/id        (comp/get-query TestCase)
                  :nexus.case.image-annotation/id (comp/get-query ImageAnnotationCase)})
   :ident (fn [] (get-case-ident props))})

(deftest reproducing-the-problem
  (behavior "Reproduce situation where the :cmmn.case/state of the first case doesn't show up in merged props"
    (let [response [{:nexus.case.image-annotation/id "case-id-00000001"
                     :cmmn.case/name                 "Annotate Image 1"
                     :cmmn.case/state                ::merge/not-found ;; Note: I captured this by logging data-tree in pre-merge
                     :>/bla                          {:nexus.case.image-annotation/id "case-id-00000001"
                                                      :cmmn.case/state                "completed"}}
                    {:nexus.case.test-case/id "case-id-00000004"
                     :cmmn.case/name          "Test Case 1",
                     :cmmn.case/state         "active"}]]      
      (assertions
        "Show that :cmmn.case/state isn't merged"
        (merge/merge-component {} CaseUnion response) =>
        {:nexus.case.image-annotation/id {"case-id-00000001" {:nexus.case.image-annotation/id "case-id-00000001"
                                                              :cmmn.case/name                 "Annotate Image 1"
                                                              ;; :cmmn.case/state             "completed" <== EXPECTED!!
                                                              :>/bla                          [:nexus.case.image-annotation/id "case-id-00000001"]}}
         :nexus.case.test-case/id        {"case-id-00000004" {:nexus.case.test-case/id "case-id-00000004"
                                                              :cmmn.case/name          "Test Case 1"
                                                              :cmmn.case/state         "active"}}}        ))))