Stack overflow when using CIDER with datahike and sail about cider HOT 5 OPEN

Must be some weird interaction with the out middleware then. (which I guessed from the stacktrace)

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Does this work if you disable the output redirection? (see https://docs.cider.mx/cider/usage/code_evaluation.html#change-the-output-destination)

(setq cider-redirect-server-output-to-repl nil)

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Yes, it does

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Condensed the reproducer to this:

(require '[sail.core :as sail]
         '[taoensso.timbre :as log])

(log/info "hello")

Datahike is unrelated, this is caused by Sail. Particularly, it is this line:

(log/merge-config!
  {:appenders {:println (log-appenders/println-appender
                          {:stream (java.io.OutputStreamWriter. System/out)})}})

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Apparently, creating such Timbre appender creates a loop in the printer graph because cider-nrepl rebinds System/out to its own wrapped printer. I haven't found yet where the loop closes and whether the action above should be allowed, but if this breaks only in CIDER, then it's probably a CIDER bug.

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