When a `clojure.test/is` form inside of a `clojure.test/deftest` form is evaluated while executing tests, and an exception is thrown, Clojure/Java prints the expected and actual values, where the actual value includes a stack trace for the exception thrown. This is useful information for developers to isolate the reason for the exception being thrown during the failed test.

ClojureScript 1.10.520 prints the actual value as the exception object, e.g. like so: `#object[Error Error: my custom exception #2]`, but never prints a stack trace.

A tiny sample project demonstrating the difference in behavior between Clojure/Java and ClojureScript can be found here: https://github.com/jafingerhut/cljs-3162-sample-project