Artifact configuration w/o file extension creates NullPointerException


#1

build.gradle:

apply plugin:'java'
  artifacts {
   runtime file:file('test_file'), builtBy:jar
}

output:

$ gradle
  FAILURE: Build failed with an exception.
  * Where:
Build file '/home/pcm/artifacts/build.gradle' line: 4
  * What went wrong:
A problem occurred evaluating root project 'artifacts'.
> Failed to notify action.
   > java.lang.NullPointerException (no error message)
  * Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
  BUILD FAILED
  Total time: 1.406 secs