NullPointerException when processing dynamic argument

[lxbr]

We use filters on collections that can be composed recursively via boolean logic. In the example below the or field takes an array of StringFilters. When the array contains a StringFilter with a constant ("blue") and another one with a dynamic argument ($color) the query execution returns an error. The NPE seems to occur at https://github.com/walmartlabs/lacinia/blob/v0.38.0/src/com/walmartlabs/lacinia/parser.clj#L637 when literal-values is {:color {:equals "blue"}} and dynamic-extractor is nil.

Setup

com.walmartlabs/lacinia {:mvn/version "0.38.0"}

(require '[com.walmartlabs.lacinia.schema :as schema]
         '[com.walmartlabs.lacinia.util :as util]
         '[com.walmartlabs.lacinia :as lacinia])

(let [schema (-> '{:queries
                   {:cars {:type :CarCollection
                           :args {:filter {:type :CarCollectionFilter}}
                           :resolve :get-cars}}
                   
                   :input-objects
                   {:CarCollectionFilter
                    {:fields {:or {:type (list :CarCollectionFilter)}
                              :color {:type :StringFilter}}}
                    
                    :StringFilter
                    {:fields {:equals {:type String}}}}
                   
                   :objects
                   {:Car
                    {:fields {:color {:type String}}}
                    
                    :CarCollection
                    {:fields {:nodes {:type (list :Car)}}}}}
                 (util/attach-resolvers {:get-cars (fn [context args value]
                                                     {:nodes []})})
                 (schema/compile))
      query "query($color: String) {
               cars(filter: {or: [{color: {equals: \"blue\"}},
                                  {color: {equals: $color}}]}) {
                 nodes {
                   color
                 }
               }
             }"
      args {:color "red"}]
  (lacinia/execute schema query args nil))

Expected result

{:data #ordered/map ([:cars #ordered/map ([:nodes ()])])}

Actual result

{:errors [{:message "java.lang.NullPointerException"}]}

[hlship]

Nice write up; this is on my radar.

[hlship]

I'm looking into this; seems like a dynamic arguments extractor is ending up as nil when it shouldn't; might be related to the heavy recursion in your input fields, but it should still work.

[hlship]

Taking a step away helps and the solution was pretty obvious once I looked into it carefully.