Unhandled parse error exception in config: "no conversion to symbol"

[pithyless]

version

clj-kondo/clj-kondo {:mvn/version "2023.07.13"}

platform

JVM (specifically clojure function via babashka task)

problem

Config had invalid reference to var, but it crashed with exception "no conversion to symbol".

Error reported:

Unexpected error. Please report an issue.
java.lang.IllegalArgumentException: no conversion to symbol
	at clojure.core$symbol.invokeStatic(core.clj:598)
	at clojure.core$symbol.invoke(core.clj:591)
	at clj_kondo.impl.config$eval4623$delayed_cfg__4624$fn__4626.invoke(config.clj:301)
	at clojure.lang.ArrayChunk.reduce(ArrayChunk.java:63)
	at clojure.core.protocols$fn__8244.invokeStatic(protocols.clj:136)
	at clojure.core.protocols$fn__8244.invoke(protocols.clj:124)
	at clojure.core.protocols$fn__8204$G__8199__8213.invoke(protocols.clj:19)
	at clojure.core.protocols$seq_reduce.invokeStatic(protocols.clj:31)
	at clojure.core.protocols$fn__8236.invokeStatic(protocols.clj:75)
	at clojure.core.protocols$fn__8236.invoke(protocols.clj:75)
	at clojure.core.protocols$fn__8178$G__8173__8191.invoke(protocols.clj:13)
	at clojure.core$reduce.invokeStatic(core.clj:6886)
	at clojure.core$reduce.invoke(core.clj:6868)
	at clj_kondo.impl.config$eval4623$delayed_cfg__4624.invoke(config.clj:300)
	at clojure.lang.AFn.applyToHelper(AFn.java:154)
	at clojure.lang.AFn.applyTo(AFn.java:144)
	at clojure.core$apply.invokeStatic(core.clj:667)
	at clojure.core$memoize$fn__6946.doInvoke(core.clj:6388)
	at clojure.lang.RestFn.invoke(RestFn.java:408)
	at clj_kondo.impl.config$eval4623$unresolved_symbol_excluded__4636.invoke(config.clj:318)
	at clj_kondo.impl.namespace$reg_unresolved_symbol_BANG_.invokeStatic(namespace.clj:349)
	at clj_kondo.impl.namespace$reg_unresolved_symbol_BANG_.invoke(namespace.clj:345)
	at clj_kondo.impl.linters$lint_var_usage.invokeStatic(linters.clj:290)
	at clj_kondo.impl.linters$lint_var_usage.invoke(linters.clj:209)
	at clj_kondo.core$run_BANG_.invokeStatic(core.clj:218)
	at clj_kondo.core$run_BANG_.invoke(core.clj:56)
	at clj_kondo.main$main.invokeStatic(main.clj:149)
	at clj_kondo.main$main.doInvoke(main.clj:135)
	at clojure.lang.RestFn.applyTo(RestFn.java:137)
	at clojure.core$apply.invokeStatic(core.clj:667)
	at clojure.core$apply.invoke(core.clj:662)
	at clj_kondo.main$_main$fn__16210.invoke(main.clj:186)
	at clj_kondo.main$_main.invokeStatic(main.clj:186)
	at clj_kondo.main$_main.doInvoke(main.clj:184)
	at clojure.lang.RestFn.applyTo(RestFn.java:137)
	at clojure.lang.Var.applyTo(Var.java:705)
	at clojure.core$apply.invokeStatic(core.clj:667)
	at clojure.main$main_opt.invokeStatic(main.clj:514)
	at clojure.main$main_opt.invoke(main.clj:510)
	at clojure.main$main.invokeStatic(main.clj:664)
	at clojure.main$main.doInvoke(main.clj:616)
	at clojure.lang.RestFn.applyTo(RestFn.java:137)
	at clojure.lang.Var.applyTo(Var.java:705)
	at clojure.main.main(main.java:40)

If you study the stacktrace, there are breadcrumbs to the source of the problem; but it was not obvious to me at first glance when linting a project.

config

{:linters
 {:unresolved-symbol {:exclude [(ns.symbol.without.slash [symbol])]}}}

expected behavior

Perhaps some kind of friendlier message for the user that there is a problem with the config? Even better if we can point to a specific line or section of the config.