xref: /freebsd/contrib/kyua/doc/test-isolation.mdoc (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
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The test programs and test cases run by .Nm are all executed in a deterministic environment. This known, clean environment serves to make the test execution as reproducible as possible and also to prevent clashes between tests that may, for example, create auxiliary files with overlapping names.

p For plain test programs and for TAP test programs, the whole test program is run under a single instance of the environment described in this page. For ATF test programs (see .Xr atf 7 ) , each individual test case .Em and test cleanup routine are executed in separate environments. l -tag -width XX t Process space Each test is executed in an independent processes. Corollary: the test can do whatever it wants to the current process (such as modify global variables) without having to undo such changes. t Session and process group The test is executed in its own session and its own process group. There is no controlling terminal attached to the session.

p Should the test spawn any children, the children should maintain the same session and process group. Modifying any of these settings prevents .Nm from being able to kill any stray subprocess as part of the cleanup phase. If modifying these settings is necessary, or if any subprocess started by the test decides to use a different process group or session, it is the responsibility of the test to ensure those subprocesses are forcibly terminated during cleanup. t Work directory The test is executed in a temporary directory automatically created by the runtime engine. Corollary: the test can write to its current directory without needing to clean any files and/or directories it creates. The runtime engine takes care to recursively delete the temporary directories after the execution of a test case. Any file systems mounted within the temporary directory are also unmounted. t Home directory The .Va HOME environment variable is set to the absolute path of the work directory. t Umask The value of the umask is set to 0022. t Environment The .Va LANG , .Va LC_ALL , .Va LC_COLLATE , .Va LC_CTYPE , .Va LC_MESSAGES , .Va LC_MONETARY , .Va LC_NUMERIC and .Va LC_TIME variables are unset.

p The .Va TZ variable is set to .Sq UTC .

p The .Va TMPDIR variable is set to the absolute path of the work directory. This is to prevent the test from mistakenly using a temporary directory outside of the automatically-managed work directory, should the test use the .Xr mktemp 3 familiy of functions. t Process limits The maximum soft core size limit is raised to its corresponding hard limit. This is a simple, best-effort attempt at allowing tests to dump core for further diagnostic purposes. t Configuration varibles The test engine may pass run-time configuration variables to the test program via the environment. The name of the configuration variable is prefixed with .Sq TEST_ENV_ so that a configuration variable of the form .Sq foo=bar becomes accessible in the environment as .Sq TEST_ENV_foo=bar . .El