diff --git a/tests/README.md b/tests/README.md new file mode 100644 index 00000000..be3bda82 --- /dev/null +++ b/tests/README.md @@ -0,0 +1,136 @@ +# Btrfs-progs tests + +Run the tests from the top directory: + +```shell +$ make test +$ make test-fsck +$ make test-convert +``` + +or selectively from the `tests/` directory: + +```shell +$ ./fsck-tests.sh +$ ./misc-tests.sh +``` + +The verbose output of the tests is logged into a file named after the test +category, eg. `fsck-tests-results.txt`. + +## Selective testing + +The test are prefixed by a number for ordering and uniquenes. To run a +particular test use: + +```shell +$ make TEST=MASK test +``` + +where `MASK` is a glob expression that will execute only tests +that match the MASK. Here the test number comes handy: + +```shell +$ make TEST=001\* test-fsck +$ TEST=001\* ./fsck-tests.sh +``` + +will run the first test in fsck-tests subdirectory. + + +## Test structure + +*tests/fsck-tests/:* + + * tests targeted at bugs that are fixable by fsck + +*tests/convert-tests/:* + + * coverage tests of ext2/3/4 and btrfs-convert options + +*tests/fuzz-tests/:* + + * collection of fuzzed or crafted images + * tests that are supposed to run various utilities on the images and not + crash + +*tests/misc-tests/:* + + * anything that does not fit to the above, the test driver script will only + execute `./test.sh` in the test directory + +*tests/common:* + + * script with helpers + +*tests/test.img:* + + * default testing image, the file is never deleted by the scripts but + truncated to 0 bytes, so it keeps it's permissions. It's eg. possible to + host it on NFS, make it `chmod a+w` for root. + + +## Other tuning, environment variables + +### Instrumentation + +It's possible to wrap the tested commands to utilities that might do more +checking or catch failures at runtime. This can be done by setting the +`INSTRUMENT` environment variable: + +```shell +INSTRUMENT=valgrind ./fuzz-tests.sh # in tests/ +make INSTRUMENT=valgrind test-fuzz # in the top directory +``` + +The variable is prepended to the command *unquoted*, all sorts of shell tricks +are possible. + +Note: instrumentation is not applied to privileged commands (anything that uses +the root helper). + +### Verbosity + +Setting the variable `TEST_LOG=tty` will print all commands executed by some of +the wrappers (`run_check` etc), other commands are silent. + +### Permissions + +Some commands require root privileges (to mount/umount, access loop devices). +It is assumed that `sudo` will work in some way (no password, password asked +and cached). Note that instrumentation is not applied in this case, for safety +reasons. You need to modify the test script instead. + +### Cleanup + +The tests are supposed to cleanup after themselves if they pass. In case of +failure, the rest of the tests are skipped and intermediate files, mounts and +loop devices are kept. This should help to investigate the test failure but at +least the mounts and loop devices need to be cleaned before the next run. + +This is partially done by the script `clean-tests.sh`, you may want to check +the loop devices as they are managed on a per-test basis. + +## New test + +1. Pick the category for the new test or fallback to `misc-tests` if not sure. For +an easy start copy an existing `test.sh` script from some test that might be +close to the purpose of your new test. + +* Use the highest unused number in the sequence, write a short descriptive title +and join by dashes `-`. + +* Write a short description of the bug and how it's teste to the comment at the +begining of `test.sh`. + +* Write the test commands, comment anything that's not obvious. + +* Test your test. Use the `TEST` variable to jump right to your test: +```shell +$ make TEST=012\* tests-misc # from top directory +$ TEST=012\* ./misc-tests.sh # from tests/ +``` + +* The commit changelog should reference a commit that either introduced or + fixed the bug (or both). Subject line of the shall mention the name of the + new directory for ease of search, eg. `btrfs-progs: tests: add 012-subvolume-sync-must-wait`