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23.4.2 Running tests using `test.regrtest`

`test.regrtest` can be used as a script to drive Python's regression test suite. Running the script by itself automatically starts running all regression tests in the `test` package. It does this by finding all modules in the package whose name starts with "`test_`", importing them, and executing the function `test_main()` if present. The names of tests to execute may also be passed to the script. Specifying a single regression test (python regrtest.py test_spam.py) will minimize output and only print whether the test passed or failed and thus minimize output.

Running `test.regrtest` directly allows what resources are available for tests to use to be set. You do this by using the -u command-line option. Run python regrtest.py -uall to turn on all resources; specifying all as an option for -u enables all possible resources. If all but one resource is desired (a more common case), a comma-separated list of resources that are not desired may be listed after all. The command python regrtest.py -uall,-audio,-largefile will run `test.regrtest` with all resources except the audio and largefile resources. For a list of all resources and more command-line options, run python regrtest.py -h.

Some other ways to execute the regression tests depend on what platform the tests are being executed on. On Unix, you can run make test at the top-level directory where Python was built. On Windows, executing rt.bat from your PCBuild directory will run all regression tests.