`oget` fails if the JS object has `:constructor` set to `null`

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
55/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Stale
Tech stack
javascript
Domain
tooling

Research direction

Start with is-prototype? in helpers.cljs, at the stack trace location, and reproduce the oget example with a JavaScript object whose constructor is null. Verify that accessing :a no longer throws when the constructor is absent, while normal prototype checks still work.

Written by the indexing model from the issue text.

Description

=> (oget #js {:constructor nil, :a 1} :a)
TypeError: Cannot read properties of null (reading 'prototype')
    at Object.oops$helpers$is_prototype_QMARK_ [as is_prototype_QMARK_] (helpers.cljs:7)
    at Object.oops$helpers$cljs_type_QMARK_ [as cljs_type_QMARK_] (helpers.cljs:19)
    at Object.oops$core$validate_object_access_dynamically [as validate_object_access_dynamically] (core.cljs:39)
    at eval (views.cljs:308)

The culprit seems to be this function:

(defn is-prototype? [o]
  (identical? (.-prototype (.-constructor o)) o))

Perhaps it should check if (.-constructor o) is not null?

Dominant language
Clojure
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Forks
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