Core GIT Tests ============== This directory holds many test scripts for core GIT tools. The first part of this short document describes how to run the tests and read their output. When fixing the tools or adding enhancements, you are strongly encouraged to add tests in this directory to cover what you are trying to fix or enhance. The later part of this short document describes how your test scripts should be organized. Running Tests ------------- The easiest way to run tests is to say "make". This runs all the tests. *** t0000-basic.sh *** ok 1 - .git/objects should be empty after git init in an empty repo. ok 2 - .git/objects should have 3 subdirectories. ok 3 - success is reported like this ... ok 43 - very long name in the index handled sanely # fixed 1 known breakage(s) # still have 1 known breakage(s) # passed all remaining 42 test(s) 1..43 *** t0001-init.sh *** ok 1 - plain ok 2 - plain with GIT_WORK_TREE ok 3 - plain bare Since the tests all output TAP (see http://testanything.org) they can be run with any TAP harness. Here's an example of parallel testing powered by a recent version of prove(1): $ prove --timer --jobs 15 ./t[0-9]*.sh [19:17:33] ./t0005-signals.sh ................................... ok 36 ms [19:17:33] ./t0022-crlf-rename.sh ............................... ok 69 ms [19:17:33] ./t0024-crlf-archive.sh .............................. ok 154 ms [19:17:33] ./t0004-unwritable.sh ................................ ok 289 ms [19:17:33] ./t0002-gitfile.sh ................................... ok 480 ms ===( 102;0 25/? 6/? 5/? 16/? 1/? 4/? 2/? 1/? 3/? 1... )=== prove and other harnesses come with a lot of useful options. The --state option in particular is very useful: # Repeat until no more failures $ prove -j 15 --state=failed,save ./t[0-9]*.sh You can give DEFAULT_TEST_TARGET=prove on the make command (or define it in config.mak) to cause "make test" to run tests under prove. GIT_PROVE_OPTS can be used to pass additional options, e.g. $ make DEFAULT_TEST_TARGET=prove GIT_PROVE_OPTS='--timer --jobs 16' test You can also run each test individually from command line, like this: $ sh ./t3010-ls-files-killed-modified.sh ok 1 - git update-index --add to add various paths. ok 2 - git ls-files -k to show killed files. ok 3 - validate git ls-files -k output. ok 4 - git ls-files -m to show modified files. ok 5 - validate git ls-files -m output. # passed all 5 test(s) 1..5 You can pass --verbose (or -v), --debug (or -d), and --immediate (or -i) command line argument to the test, or by setting GIT_TEST_OPTS appropriately before running "make". --verbose:: This makes the test more verbose. Specifically, the command being run and their output if any are also output. --debug:: This may help the person who is developing a new test. It causes the command defined with test_debug to run. --immediate:: This causes the test to immediately exit upon the first failed test. --long-tests:: This causes additional long-running tests to be run (where available), for more exhaustive testing. --valgrind:: Execute all Git binaries with valgrind and exit with status 126 on errors (just like regular tests, this will only stop the test script when running under -i). Valgrind errors go to stderr, so you might want to pass the -v option, too. Since it makes no sense to run the tests with --valgrind and not see any output, this option implies --verbose. For convenience, it also implies --tee. --tee:: In addition to printing the test output to the terminal, write it to files named 't/test-results/$TEST_NAME.out'. As the names depend on the tests' file names, it is safe to run the tests with this option in parallel. --with-dashes:: By default tests are run without dashed forms of commands (like git-commit) in the PATH (it only uses wrappers from ../bin-wrappers). Use this option to include the build directory (..) in the PATH, which contains all the dashed forms of commands. This option is currently implied by other options like --valgrind and GIT_TEST_INSTALLED. --root=:: Create "trash" directories used to store all temporary data during testing under , instead of the t/ directory. Using this option with a RAM-based filesystem (such as tmpfs) can massively speed up the test suite. You can also set the GIT_TEST_INSTALLED environment variable to the bindir of an existing git installation to test that installation. You still need to have built this git sandbox, from which various test-* support programs, templates, and perl libraries are used. If your installed git is incomplete, it will silently test parts of your built version instead. When using GIT_TEST_INSTALLED, you can also set GIT_TEST_EXEC_PATH to override the location of the dashed-form subcommands (what GIT_EXEC_PATH would be used for during normal operation). GIT_TEST_EXEC_PATH defaults to `$GIT_TEST_INSTALLED/git --exec-path`. Skipping Tests -------------- In some environments, certain tests have no way of succeeding due to platform limitation, such as lack of 'unzip' program, or filesystem that do not allow arbitrary sequence of non-NUL bytes as pathnames. You should be able to say something like $ GIT_SKIP_TESTS=t9200.8 sh ./t9200-git-cvsexport-commit.sh and even: $ GIT_SKIP_TESTS='t[0-4]??? t91?? t9200.8' make to omit such tests. The value of the environment variable is a SP separated list of patterns that tells which tests to skip, and either can match the "t[0-9]{4}" part to skip the whole test, or t[0-9]{4} followed by ".$number" to say which particular test to skip. Note that some tests in the existing test suite rely on previous test item, so you cannot arbitrarily disable one and expect the remainder of test to check what the test originally was intended to check. Naming Tests ------------ The test files are named as: tNNNN-commandname-details.sh where N is a decimal digit. First digit tells the family: 0 - the absolute basics and global stuff 1 - the basic commands concerning database 2 - the basic commands concerning the working tree 3 - the other basic commands (e.g. ls-files) 4 - the diff commands 5 - the pull and exporting commands 6 - the revision tree commands (even e.g. merge-base) 7 - the porcelainish commands concerning the working tree 8 - the porcelainish commands concerning forensics 9 - the git tools Second digit tells the particular command we are testing. Third digit (optionally) tells the particular switch or group of switches we are testing. If you create files under t/ directory (i.e. here) that is not the top-level test script, never name the file to match the above pattern. The Makefile here considers all such files as the top-level test script and tries to run all of them. A care is especially needed if you are creating a common test library file, similar to test-lib.sh, because such a library file may not be suitable for standalone execution. Writing Tests ------------- The test script is written as a shell script. It should start with the standard "#!/bin/sh" with copyright notices, and an assignment to variable 'test_description', like this: #!/bin/sh # # Copyright (c) 2005 Junio C Hamano # test_description='xxx test (option --frotz) This test registers the following structure in the cache and tries to run git-ls-files with option --frotz.' Source 'test-lib.sh' -------------------- After assigning test_description, the test script should source test-lib.sh like this: . ./test-lib.sh This test harness library does the following things: - If the script is invoked with command line argument --help (or -h), it shows the test_description and exits. - Creates an empty test directory with an empty .git/objects database and chdir(2) into it. This directory is 't/trash directory.$test_name_without_dotsh', with t/ subject to change by the --root option documented above. - Defines standard test helper functions for your scripts to use. These functions are designed to make all scripts behave consistently when command line arguments --verbose (or -v), --debug (or -d), and --immediate (or -i) is given. Do's, don'ts & things to keep in mind ------------------------------------- Here are a few examples of things you probably should and shouldn't do when writing tests. Do: - Put all code inside test_expect_success and other assertions. Even code that isn't a test per se, but merely some setup code should be inside a test assertion. - Chain your test assertions Write test code like this: git merge foo && git push bar && test ... Instead of: git merge hla git push gh test ... That way all of the commands in your tests will succeed or fail. If you must ignore the return value of something, consider using a helper function (e.g. use sane_unset instead of unset, in order to avoid unportable return value for unsetting a variable that was already unset), or prepending the command with test_might_fail or test_must_fail. - Check the test coverage for your tests. See the "Test coverage" below. Don't blindly follow test coverage metrics, they're a good way to spot if you've missed something. If a new function you added doesn't have any coverage you're probably doing something wrong, but having 100% coverage doesn't necessarily mean that you tested everything. Tests that are likely to smoke out future regressions are better than tests that just inflate the coverage metrics. - When a test checks for an absolute path that a git command generated, construct the expected value using $(pwd) rather than $PWD, $TEST_DIRECTORY, or $TRASH_DIRECTORY. It makes a difference on Windows, where the shell (MSYS bash) mangles absolute path names. For details, see the commit message of 4114156ae9. Don't: - exit() within a