# Btrfs-progs tests
+A testsuite covering functionality of btrfs-progs, ie. the checker, image, mkfs
+and similar tools. There are no additional requirements on kernel features
+(other than `CONFIG_BTRFS_FS` built-in or module), the
+tests build on top of the core functionality like snapshots and device
+management. In some cases optional features are turned on by mkfs and the
+filesystem image could be mounted, such tests might fail if there's lack of
+support.
+
+## Quick start
+
Run the tests from the top directory:
```shell
## Selective testing
-The test are prefixed by a number for ordering and uniquenes. To run a
+The tests are prefixed by a number for ordering and uniqueness. To run a
particular test use:
```shell
* tests that are supposed to run various utilities on the images and not
crash
+*tests/cli-tests/:*
+
+ * tests for command line interface, option coverage, weird option combinations that should not work
+ * not necessary to do any functional testing, could be rather lightweight
+ * functional tests should go to to other test dirs
+ * the driver script will only execute `./test.sh` in the test directory
+
*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:*
+*tests/common, tests/common.convert:*
- * script with helpers
+ * script with shell helpers, separated by functionality
*tests/test.img:*
Note: instrumentation is not applied to privileged commands (anything that uses
the root helper).
-### Verbosity
+### Verbosity, test tuning
+
+* `TEST_LOG=tty` -- setting the variable will print all commands executed by
+ some of the wrappers (`run_check` etc), other commands are not printed to the
+ terminal (but the full output is in the log)
+
+* `TEST_LOG=dump` -- dump the entire testing log when a test fails
+
+* `TEST_ENABLE_OVERRIDE` -- defined either as make arguments or via
+ `tests/common.local` to enable additional arguments to some commands, using
+ the variable(s) below (default: false, enable by setting to 'true')
+
+* `TEST_ARGS_CHECK` -- user-defined arguments to `btrfs check`, before the
+ test-specific arguments
-Setting the variable `TEST_LOG=tty` will print all commands executed by some of
-the wrappers (`run_check` etc), other commands are silent.
+Multiple values can be separated by `,`.
### Permissions
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.
+### Prototyping tests, quick tests
+
+There's a script `test-console.sh` that will run shell commands in a loop and
+logs the output with the testing environment set up.
+
+### Runtime dependencies
+
+The tests use some common system utilities like `find`, `rm`, `dd`. Additionally,
+specific tests need the following packages installed: `acl`, `attr`,
+`e2fsprogs`, `reiserfsprogs`
+
+
## 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.
+close to the purpose of your new test. The environment setup includes the
+common scripts and/or prepares the test devices. Other scripts contain examples
+how to do mkfs, mount, unmount, check, etc.
-* Use the highest unused number in the sequence, write a short descriptive title
-and join by dashes `-`.
+2. Use the highest unused number in the sequence, write a short descriptive title
+and join by dashes `-`. This will become the directory name, eg. `012-subvolume-sync-must-wait`.
-* Write a short description of the bug and how it's teste to the comment at the
-begining of `test.sh`.
+3. Write a short description of the bug and how it's tested to the comment at the
+begining of `test.sh`. You don't need to add the file to git yet.
-* Write the test commands, comment anything that's not obvious.
+4. Write the test commands, comment anything that's not obvious.
-* Test your test. Use the `TEST` variable to jump right to your test:
+5. **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
+6. 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`
+
+
+### Crafted/fuzzed images
+
+Images that are create by fuzzing or specially crafted to trigger some error
+conditions should be added to the directory *fuzz-tests/images*, accompanied by
+a textual description of the source (bugzilla, mail), the reporter, brief
+description of the problem or the stack trace.
+
+If you have a fix for the problem, please submit it prior to the test image, so
+the fuzz tests always succeed when run on random checked out. This helps
+bisectability.
+
+
+# Coding style, best practices
+
+## do
+
+* quote all variables by default, any path, even the TOP could need that, and
+ we use it everywhere
+ * there are exceptions:
+ * `$SUDO_HELPER` as it might be intentionally unset
+ * the variable is obviously set to a value that does not require it
+* use `#!/bin/bash` explicitly
+* check for all external dependencies (`check_prereq_global`)
+* check for internal dependencies (`check_prereq`), though the basic set is
+ always built when the tests are started through make
+* use functions instead of repeating code
+ * generic helpers could be factored to the `common` script
+* cleanup after successful test
+* use common helpers and variables
+
+## do not
+
+* pull external dependencies if we can find a way to replace them: example is
+ `xfs_io` that's conveniently used in fstests but we'd require `xfsprogs`,
+ so use `dd` instead
+* throw away (redirect to */dev/null*) output of commands unless it's justified
+ (ie. really too much text, unnecessary slowdown) -- the test output log is
+ regenerated all the time and we need to be able to analyze test failures or
+ just observe how the tests progress
+* cleanup after failed test -- the testsuite stops on first failure and the
+ developer can eg. access the environment that the test created and do further
+ debugging
+ * this might change in the future so the tests cover as much as possible, but
+ this would require to enhance all tests with a cleanup phase
projects / platform / upstream / btrfs-progs.git / blobdiff