(CLJS) A "finally" in a "try" in a "go" block is skipped in f a string is thrown.
Description
Environment
org.clojure/clojure "1.8.0"
org.clojure/clojurescript "1.9.229"
org.clojure/core.async "0.3.442"
Activity
Alex Miller March 31, 2020 at 7:54 PM
Released in core.async 1.1.582
David Nolen March 31, 2020 at 6:46 PM
Kevin Downey January 10, 2019 at 12:21 AM
the patch on https://dev.clojure.org/jira/browse/ASYNC-184 solves this by replacing the (catch js/Object ...) in the macro expansion with (catch :default ...)
import January 9, 2019 at 10:46 AM
Comment made by: hubert
Sorry for the typo. The correct title should have been:
(CLJS) A "finally" in a "try" in a "go" block is skipped if a string is thrown.
Kevin Downey July 13, 2017 at 8:39 PM
The issue is likely https://github.com/clojure/core.async/blob/17112aca9b07ebba6ce760ca01d117c24c80cc9a/src/main/clojure/cljs/core/async/impl/ioc_macros.clj#L861
If that is the case you will see this behavior when anything that isn't caught with js/Object (I know that is the case for strings and numbers, not sure what else). The finally isn't being skipped, the go block state machine is completely failing to handling the thrown thing, and completely bailing
In ClojureScript a "finally" is ignored if a string is thrown and the enclosing "try" is in a "go" block.
Example code:
(ns demo
(:require-macros
[cljs.core.async.macros :refer [go]]))
;; Prints: "in a finally"
(go (try (throw (ex-info "THROWN" nil)) (finally (println "in a finally"))))
;; Prints: "in a finally"
(go (try (throw (js/Exception. "THROWN")) (finally (println "in a finally"))))
;; Prints: "in a finally"
(go (try (throw (#js {})) (finally (println "in a finally"))))
;; Prints: "in a finally"
(try (throw "THROWN") (finally (println "in a finally")))
;; Prints: nothing
(go (try (throw "THROWN") (finally (println "in a finally"))))