java.lang.IllegalStateException: This PooledParser was not returned to the pool properly #669
Description
An attempt to upgrade to 3.8.0 failed in jenkinsci/jenkins#8710 / https://ci.jenkins.io/job/Core/job/jenkins/job/PR-8710/ with intermittent errors of the form
Caused by: java.lang.IllegalStateException: This PooledParser was not returned to the pool properly
at org.htmlunit.WebClient$PooledCSS3Parser.markInUse(WebClient.java:3050)
at org.htmlunit.WebClient$CSS3ParserPool.get(WebClient.java:2999)
at org.htmlunit.WebClient.getCSS3Parser(WebClient.java:2961)
at org.htmlunit.html.DomNode.getSelectorList(DomNode.java:1869)
at org.htmlunit.html.DomNode.querySelectorAll(DomNode.java:1838)
at org.htmlunit.javascript.host.dom.Document.querySelectorAll(Document.java:1067)
at jdk.internal.reflect.GeneratedMethodAccessor46.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at org.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:222)
... 35 more
introduced in #664 which cannot be reproduced locally or even consistently in CI. The failures have been observed mostly on Windows (slower infrastructure) but also occasionally on Linux. The failures often disappear when the test is run a second time. We have rolled back to 3.7.0.