The test class TestInjection generated by maven-hpi-plugin fails to run the test suite with a timeout exception when updating jenkins-test-harness from 2.56 to 2.57 on Windows agent.

The same mvn install command run on a Linux agent run fine.

After investigation, the reason is that JellyTestSuite is based on HudsonTestCase, and HudsonTestCase does not work on the Windows agent with a jetty above 9.4.6.v20170531.

Between jenkins-test-harness-2:56 and jenkins-test-harness:2.57 jetty version has changed from 9.4.5.v20170502 to 9.4.22.v20191022.

Setting jetty version to 9.4.6.v20170531 in maven dependencies with jenkins-test-harness:2.57 (and above) solve the issue.

JellyTestSuiteBuilder should be updated to use JenkinsRule and not the deprecated HudsonTestCase.

https://github.com/jenkinsci/jenkins-test-harness/blob/0e0ec3c9ccbe6314d488faa248e2f50f312f3cad/src/main/java/org/jvnet/hudson/test/JellyTestSuiteBuilder.java#L138

Link to maven-hpi-plugin code that generate the TestInjection class:
https://github.com/jenkinsci/maven-hpi-plugin/blob/master/src/main/java/org/jenkinsci/maven/plugins/hpi/TestInsertionMojo.java