If classpath directory contains a directory it causes exception in Spark runner staging

Run the unit test  SparkPipelineStateTest.testBatchPipelineRunningState in IntelliJ IDEA on my mac, get the IllegalArgumentException in the console output. I check the source code, and find the result of PipelineResources.detectClassPathResourcesToStage contains directory, which is the cause of the exception.

See the attached file 'addJar_exception.jpg' for detail, and the result of PipelineResources.detectClassPathResourcesToStage

is showed in attached file 'files_contains_dir.jpg' during debug.