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Diffstat (limited to 't/README')
| -rw-r--r-- | t/README | 341 |
1 files changed, 293 insertions, 48 deletions
@@ -1,7 +1,7 @@ -Core GIT Tests +Core Git Tests ============== -This directory holds many test scripts for core GIT tools. The +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. @@ -69,7 +69,8 @@ You can also run each test individually from command line, like this: 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". +appropriately before running "make". Short options can be bundled, i.e. +'-d -v' is the same as '-dv'. -v:: --verbose:: @@ -154,6 +155,7 @@ appropriately before running "make". As the names depend on the tests' file names, it is safe to run the tests with this option in parallel. +-V:: --verbose-log:: Write verbose output to the same logfile as `--tee`, but do _not_ write it to stdout. Unlike `--tee --verbose`, this option @@ -169,6 +171,15 @@ appropriately before running "make". implied by other options like --valgrind and GIT_TEST_INSTALLED. +--no-bin-wrappers:: + By default, the test suite uses the wrappers in + `../bin-wrappers/` to execute `git` and friends. With this option, + `../git` and friends are run directly. This is not recommended + in general, as the wrappers contain safeguards to ensure that no + files from an installed Git are used, but can speed up test runs + especially on platforms where running shell scripts is expensive + (most notably, Windows). + --root=<directory>:: Create "trash" directories used to store all temporary data during testing under <directory>, instead of the t/ directory. @@ -185,6 +196,29 @@ appropriately before running "make". this feature by setting the GIT_TEST_CHAIN_LINT environment variable to "1" or "0", respectively. +--stress:: + Run the test script repeatedly in multiple parallel jobs until + one of them fails. Useful for reproducing rare failures in + flaky tests. The number of parallel jobs is, in order of + precedence: the value of the GIT_TEST_STRESS_LOAD + environment variable, or twice the number of available + processors (as shown by the 'getconf' utility), or 8. + Implies `--verbose -x --immediate` to get the most information + about the failure. Note that the verbose output of each test + job is saved to 't/test-results/$TEST_NAME.stress-<nr>.out', + and only the output of the failed test job is shown on the + terminal. The names of the trash directories get a + '.stress-<nr>' suffix, and the trash directory of the failed + test job is renamed to end with a '.stress-failed' suffix. + +--stress-jobs=<N>:: + Override the number of parallel jobs. Implies `--stress`. + +--stress-limit=<N>:: + When combined with --stress run the test script repeatedly + this many times in each of the parallel jobs or until one of + them fails, whichever comes first. Implies `--stress`. + 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 @@ -224,16 +258,21 @@ For an individual test suite --run could be used to specify that only some tests should be run or that some tests should be excluded from a run. -The argument for --run is a list of individual test numbers or -ranges with an optional negation prefix that define what tests in -a test suite to include in the run. A range is two numbers -separated with a dash and matches a range of tests with both ends -been included. You may omit the first or the second number to -mean "from the first test" or "up to the very last test" -respectively. - -Optional prefix of '!' means that the test or a range of tests -should be excluded from the run. +The argument for --run, <test-selector>, is a list of description +substrings or globs or individual test numbers or ranges with an +optional negation prefix (of '!') that define what tests in a test +suite to include (or exclude, if negated) in the run. A range is two +numbers separated with a dash and matches a range of tests with both +ends been included. You may omit the first or the second number to +mean "from the first test" or "up to the very last test" respectively. + +The argument to --run is split on commas into separate strings, +numbers, and ranges, and picks all tests that match any of the +individual selection criteria. If the substring of the description +text that you want to match includes a comma, use the glob character +'?' instead. For example --run='rebase,merge?cherry-pick' would match +on all tests that match either the glob *rebase* or the glob +*merge?cherry-pick*. If --run starts with an unprefixed number or range the initial set of tests to run is empty. If the first item starts with '!' @@ -241,9 +280,6 @@ all the tests are added to the initial set. After initial set is determined every test number or range is added or excluded from the set one by one, from left to right. -Individual numbers or ranges could be separated either by a space -or a comma. - For example, to run only tests up to a specific test (21), one could do this: @@ -256,7 +292,7 @@ or this: Common case is to run several setup tests (1, 2, 3) and then a specific test (21) that relies on that setup: - $ sh ./t9200-git-cvsexport-commit.sh --run='1 2 3 21' + $ sh ./t9200-git-cvsexport-commit.sh --run='1,2,3,21' or: @@ -264,17 +300,17 @@ or: or: - $ sh ./t9200-git-cvsexport-commit.sh --run='-3 21' + $ sh ./t9200-git-cvsexport-commit.sh --run='-3,21' As noted above, the test set is built by going through the items from left to right, so this: - $ sh ./t9200-git-cvsexport-commit.sh --run='1-4 !3' + $ sh ./t9200-git-cvsexport-commit.sh --run='1-4,!3' will run tests 1, 2, and 4. Items that come later have higher precedence. It means that this: - $ sh ./t9200-git-cvsexport-commit.sh --run='!3 1-4' + $ sh ./t9200-git-cvsexport-commit.sh --run='!3,1-4' would just run tests from 1 to 4, including 3. @@ -283,6 +319,18 @@ test in the test suite except from 7 up to 11: $ sh ./t9200-git-cvsexport-commit.sh --run='!7-11' +Sometimes there may be multiple tests with e.g. "setup" in their name +that are needed and rather than figuring out the number for all of them +we can just use "setup" as a substring/glob to match against the test +description: + + $ sh ./t0050-filesystem.sh --run=setup,9-11 + +or one could select both the setup tests and the rename ones (assuming all +relevant tests had those words in their descriptions): + + $ sh ./t0050-filesystem.sh --run=setup,rename + Some tests in a test suite rely on the previous tests performing certain actions, specifically some tests are designated as "setup" test, so you cannot _arbitrarily_ disable one test and @@ -301,9 +349,27 @@ that cannot be easily covered by a few specific test cases. These could be enabled by running the test suite with correct GIT_TEST_ environment set. +GIT_TEST_FAIL_PREREQS=<boolean> fails all prerequisites. This is +useful for discovering issues with the tests where say a later test +implicitly depends on an optional earlier test. + +There's a "FAIL_PREREQS" prerequisite that can be used to test for +whether this mode is active, and e.g. skip some tests that are hard to +refactor to deal with it. The "SYMLINKS" prerequisite is currently +excluded as so much relies on it, but this might change in the future. + +GIT_TEST_GETTEXT_POISON=<boolean> turns all strings marked for +translation into gibberish if true. Used for spotting those tests that +need to be marked with a C_LOCALE_OUTPUT prerequisite when adding more +strings for translation. See "Testing marked strings" in po/README for +details. + GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole test suite. Accept any boolean values that are accepted by git-config. +GIT_TEST_PROTOCOL_VERSION=<n>, when set, makes 'protocol.version' +default to n. + GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon pack-objects code path where there are more than 1024 packs even if the actual number of packs in repository is below this limit. Accept @@ -315,6 +381,64 @@ packs on demand. This normally only happens when the object size is over 2GB. This variable forces the code path on any object larger than <n> bytes. +GIT_TEST_OE_DELTA_SIZE=<n> exercises the uncommon pack-objects code +path where deltas larger than this limit require extra memory +allocation for bookkeeping. + +GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES=<boolean> checks that cache-tree +records are valid when the index is written out or after a merge. This +is mostly to catch missing invalidation. Default is true. + +GIT_TEST_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to +be written after every 'git commit' command, and overrides the +'core.commitGraph' setting to true. + +GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS=<boolean>, when true, forces +commit-graph write to compute and write changed path Bloom filters for +every 'git commit-graph write', as if the `--changed-paths` option was +passed in. + +GIT_TEST_FSMONITOR=$PWD/t7519/fsmonitor-all exercises the fsmonitor +code path for utilizing a file system monitor to speed up detecting +new or changed files. + +GIT_TEST_INDEX_VERSION=<n> exercises the index read/write code path +for the index version specified. Can be set to any valid version +(currently 2, 3, or 4). + +GIT_TEST_PACK_SPARSE=<boolean> if disabled will default the pack-objects +builtin to use the non-sparse object walk. This can still be overridden by +the --sparse command-line argument. + +GIT_TEST_PRELOAD_INDEX=<boolean> exercises the preload-index code path +by overriding the minimum number of cache entries required per thread. + +GIT_TEST_ADD_I_USE_BUILTIN=<boolean>, when true, enables the +built-in version of git add -i. See 'add.interactive.useBuiltin' in +git-config(1). + +GIT_TEST_INDEX_THREADS=<n> enables exercising the multi-threaded loading +of the index for the whole test suite by bypassing the default number of +cache entries and thread minimums. Setting this to 1 will make the +index loading single threaded. + +GIT_TEST_MULTI_PACK_INDEX=<boolean>, when true, forces the multi-pack- +index to be written after every 'git repack' command, and overrides the +'core.multiPackIndex' setting to true. + +GIT_TEST_SIDEBAND_ALL=<boolean>, when true, overrides the +'uploadpack.allowSidebandAll' setting to true, and when false, forces +fetch-pack to not request sideband-all (even if the server advertises +sideband-all). + +GIT_TEST_DISALLOW_ABBREVIATED_OPTIONS=<boolean>, when true (which is +the default when running tests), errors out when an abbreviated option +is used. + +GIT_TEST_DEFAULT_HASH=<hash-algo> specifies which hash algorithm to +use in the test scripts. Recognized values for <hash-algo> are "sha1" +and "sha256". + Naming Tests ------------ @@ -382,20 +506,21 @@ This test harness library does the following things: - Creates an empty test directory with an empty .git/objects database and chdir(2) into it. This directory is 't/trash directory.$test_name_without_dotsh', with t/ subject to change by - the --root option documented above. + the --root option documented above, and a '.stress-<N>' suffix + appended by the --stress option. - 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 -------------------------------------- +Do's & don'ts +------------- Here are a few examples of things you probably should and shouldn't do when writing tests. -Do: +Here are the "do's:" - Put all code inside test_expect_success and other assertions. @@ -440,16 +565,56 @@ Do: Windows, where the shell (MSYS bash) mangles absolute path names. For details, see the commit message of 4114156ae9. -Don't: + - Remember that inside the <script> part, the standard output and + standard error streams are discarded, and the test harness only + reports "ok" or "not ok" to the end user running the tests. Under + --verbose, they are shown to help debug the tests. + + - Be careful when you loop + + You may need to verify multiple things in a loop, but the + following does not work correctly: + + test_expect_success 'test three things' ' + for i in one two three + do + test_something "$i" + done && + test_something_else + ' + + Because the status of the loop itself is the exit status of the + test_something in the last round, the loop does not fail when + "test_something" for "one" or "two" fails. This is not what you + want. + + Instead, you can break out of the loop immediately when you see a + failure. Because all test_expect_* snippets are executed inside + a function, "return 1" can be used to fail the test immediately + upon a failure: + + test_expect_success 'test three things' ' + for i in one two three + do + test_something "$i" || return 1 + done && + test_something_else + ' - - exit() within a <script> part. + Note that we still &&-chain the loop to propagate failures from + earlier commands. + + +And here are the "don'ts:" + + - Don't exit() within a <script> part. The harness will catch this as a programming error of the test. Use test_done instead if you need to stop the tests early (see "Skipping tests" below). - - use '! git cmd' when you want to make sure the git command exits - with failure in a controlled way by calling "die()". Instead, + - Don't use '! git cmd' when you want to make sure the git command + exits with failure in a controlled way by calling "die()". Instead, use 'test_must_fail git cmd'. This will signal a failure if git dies in an unexpected way (e.g. segfault). @@ -457,8 +622,35 @@ Don't: platform commands; just use '! cmd'. We are not in the business of verifying that the world given to us sanely works. - - use perl without spelling it as "$PERL_PATH". This is to help our - friends on Windows where the platform Perl often adds CR before + - Don't feed the output of a git command to a pipe, as in: + + git -C repo ls-files | + xargs -n 1 basename | + grep foo + + which will discard git's exit code and may mask a crash. In the + above example, all exit codes are ignored except grep's. + + Instead, write the output of that command to a temporary + file with ">" or assign it to a variable with "x=$(git ...)" rather + than pipe it. + + - Don't use command substitution in a way that discards git's exit + code. When assigning to a variable, the exit code is not discarded, + e.g.: + + x=$(git cat-file -p $sha) && + ... + + is OK because a crash in "git cat-file" will cause the "&&" chain + to fail, but: + + test "refs/heads/foo" = "$(git symbolic-ref HEAD)" + + is not OK and a crash in git could go undetected. + + - Don't use perl without spelling it as "$PERL_PATH". This is to help + our friends on Windows where the platform Perl often adds CR before the end of line, and they bundle Git with a version of Perl that does not do so, whose path is specified with $PERL_PATH. Note that we provide a "perl" function which uses $PERL_PATH under the hood, so @@ -466,17 +658,17 @@ Don't: (but you do, for example, on a shebang line or in a sub script created via "write_script"). - - use sh without spelling it as "$SHELL_PATH", when the script can - be misinterpreted by broken platform shell (e.g. Solaris). + - Don't use sh without spelling it as "$SHELL_PATH", when the script + can be misinterpreted by broken platform shell (e.g. Solaris). - - chdir around in tests. It is not sufficient to chdir to + - Don't chdir around in tests. It is not sufficient to chdir to somewhere and then chdir back to the original location later in the test, as any intermediate step can fail and abort the test, causing the next test to start in an unexpected directory. Do so inside a subshell if necessary. - - save and verify the standard error of compound commands, i.e. group - commands, subshells, and shell functions (except test helper + - Don't save and verify the standard error of compound commands, i.e. + group commands, subshells, and shell functions (except test helper functions like 'test_must_fail') like this: ( cd dir && git cmd ) 2>error && @@ -491,7 +683,7 @@ Don't: ( cd dir && git cmd 2>../error ) && test_cmp expect error - - Break the TAP output + - Don't break the TAP output The raw output from your test may be interpreted by a TAP harness. TAP harnesses will ignore everything they don't know about, but don't step @@ -511,13 +703,6 @@ Don't: but the best indication is to just run the tests with prove(1), it'll complain if anything is amiss. -Keep in mind: - - - Inside the <script> part, the standard output and standard error - streams are discarded, and the test harness only reports "ok" or - "not ok" to the end user running the tests. Under --verbose, they - are shown to help debugging the tests. - Skipping tests -------------- @@ -754,6 +939,26 @@ library for your script to use. ... ' + - test_atexit <script> + + Prepend <script> to a list of commands to run unconditionally to + clean up before the test script exits, e.g. to stop a daemon: + + test_expect_success 'test git daemon' ' + git daemon & + daemon_pid=$! && + test_atexit 'kill $daemon_pid' && + hello world + ' + + The commands will be executed before the trash directory is removed, + i.e. the atexit commands will still be able to access any pidfiles or + socket files. + + Note that these commands will be run even when a test script run + with '--immediate' fails. Be careful with your atexit commands to + minimize any changes to the failed state. + - test_write_lines <lines> Write <lines> on standard output, one line per argument. @@ -802,6 +1007,46 @@ library for your script to use. the symbolic link in the file system and a part that does; then only the latter part need be protected by a SYMLINKS prerequisite (see below). + - test_oid_init + + This function loads facts and useful object IDs related to the hash + algorithm(s) in use from the files in t/oid-info. + + - test_oid_cache + + This function reads per-hash algorithm information from standard + input (usually a heredoc) in the format described in + t/oid-info/README. This is useful for test-specific values, such as + object IDs, which must vary based on the hash algorithm. + + Certain fixed values, such as hash sizes and common placeholder + object IDs, can be loaded with test_oid_init (described above). + + - test_oid <key> + + This function looks up a value for the hash algorithm in use, based + on the key given. The value must have been loaded using + test_oid_init or test_oid_cache. Providing an unknown key is an + error. + + - yes [<string>] + + This is often seen in modern UNIX but some platforms lack it, so + the test harness overrides the platform implementation with a + more limited one. Use this only when feeding a handful lines of + output to the downstream---unlike the real version, it generates + only up to 99 lines. + + - test_bool_env <env-variable-name> <default-value> + + Given the name of an environment variable with a bool value, + normalize its value to a 0 (true) or 1 (false or empty string) + return code. Return with code corresponding to the given default + value if the variable is unset. + Abort the test script if either the value of the variable or the + default are not valid bool values. + + Prerequisites ------------- @@ -890,21 +1135,21 @@ Tips for Writing Tests As with any programming projects, existing programs are the best source of the information. However, do _not_ emulate t0000-basic.sh when writing your tests. The test is special in -that it tries to validate the very core of GIT. For example, it +that it tries to validate the very core of Git. For example, it knows that there will be 256 subdirectories under .git/objects/, and it knows that the object ID of an empty tree is a certain 40-byte string. This is deliberately done so in t0000-basic.sh because the things the very basic core test tries to achieve is -to serve as a basis for people who are changing the GIT internal +to serve as a basis for people who are changing the Git internals drastically. For these people, after making certain changes, not seeing failures from the basic test _is_ a failure. And -such drastic changes to the core GIT that even changes these +such drastic changes to the core Git that even changes these otherwise supposedly stable object IDs should be accompanied by an update to t0000-basic.sh. However, other tests that simply rely on basic parts of the core -GIT working properly should not have that level of intimate -knowledge of the core GIT internals. If all the test scripts +Git working properly should not have that level of intimate +knowledge of the core Git internals. If all the test scripts hardcoded the object IDs like t0000-basic.sh does, that defeats the purpose of t0000-basic.sh, which is to isolate that level of validation in one place. Your test also ends up needing |