In Autotest, the src/third_party/autotest/files/utils/run_pylint.py script returns 0 (success) and doesn't emit any error output if the argument file to be examined doesn't exist.

To reproduce:
Navigate to the autotest/files directory.
Execute ./utils/run_pylint.py SomePathAndFileThatDoesNotExist
Note that no output or errors are printed.
Execute echo $? 
Note that it returns 0 (success).

Expected behavior:
If directed to analyze a file that does not exist, an error should be returned.