1Core GIT Tests 2============== 3 4This directory holds many test scripts for core GIT tools. The 5first part of this short document describes how to run the tests 6and read their output. 7 8When fixing the tools or adding enhancements, you are strongly 9encouraged to add tests in this directory to cover what you are 10trying to fix or enhance. The later part of this short document 11describes how your test scripts should be organized. 12 13 14Running Tests 15------------- 16 17The easiest way to run tests is to say "make". This runs all 18the tests. 19 20 *** t0000-basic.sh *** 21 ok 1 - .git/objects should be empty after git init in an empty repo. 22 ok 2 - .git/objects should have 3 subdirectories. 23 ok 3 - success is reported like this 24 ... 25 ok 43 - very long name in the index handled sanely 26 # fixed 1 known breakage(s) 27 # still have 1 known breakage(s) 28 # passed all remaining 42 test(s) 29 1..43 30 *** t0001-init.sh *** 31 ok 1 - plain 32 ok 2 - plain with GIT_WORK_TREE 33 ok 3 - plain bare 34 35Since the tests all output TAP (see http://testanything.org) they can 36be run with any TAP harness. Here's an example of parallel testing 37powered by a recent version of prove(1): 38 39 $ prove --timer --jobs 15 ./t[0-9]*.sh 40 [19:17:33] ./t0005-signals.sh ................................... ok 36 ms 41 [19:17:33] ./t0022-crlf-rename.sh ............................... ok 69 ms 42 [19:17:33] ./t0024-crlf-archive.sh .............................. ok 154 ms 43 [19:17:33] ./t0004-unwritable.sh ................................ ok 289 ms 44 [19:17:33] ./t0002-gitfile.sh ................................... ok 480 ms 45 ===( 102;0 25/? 6/? 5/? 16/? 1/? 4/? 2/? 1/? 3/? 1... )=== 46 47prove and other harnesses come with a lot of useful options. The 48--state option in particular is very useful: 49 50 # Repeat until no more failures 51 $ prove -j 15 --state=failed,save ./t[0-9]*.sh 52 53You can give DEFAULT_TEST_TARGET=prove on the make command (or define it 54in config.mak) to cause "make test" to run tests under prove. 55GIT_PROVE_OPTS can be used to pass additional options, e.g. 56 57 $ make DEFAULT_TEST_TARGET=prove GIT_PROVE_OPTS='--timer --jobs 16' test 58 59You can also run each test individually from command line, like this: 60 61 $ sh ./t3010-ls-files-killed-modified.sh 62 ok 1 - git update-index --add to add various paths. 63 ok 2 - git ls-files -k to show killed files. 64 ok 3 - validate git ls-files -k output. 65 ok 4 - git ls-files -m to show modified files. 66 ok 5 - validate git ls-files -m output. 67 # passed all 5 test(s) 68 1..5 69 70You can pass --verbose (or -v), --debug (or -d), and --immediate 71(or -i) command line argument to the test, or by setting GIT_TEST_OPTS 72appropriately before running "make". 73 74-v:: 75--verbose:: 76 This makes the test more verbose. Specifically, the 77 command being run and their output if any are also 78 output. 79 80--verbose-only=<pattern>:: 81 Like --verbose, but the effect is limited to tests with 82 numbers matching <pattern>. The number matched against is 83 simply the running count of the test within the file. 84 85-x:: 86 Turn on shell tracing (i.e., `set -x`) during the tests 87 themselves. Implies `--verbose`. 88 Ignored in test scripts that set the variable 'test_untraceable' 89 to a non-empty value, unless it's run with a Bash version 90 supporting BASH_XTRACEFD, i.e. v4.1 or later. 91 92-d:: 93--debug:: 94 This may help the person who is developing a new test. 95 It causes the command defined with test_debug to run. 96 The "trash" directory (used to store all temporary data 97 during testing) is not deleted even if there are no 98 failed tests so that you can inspect its contents after 99 the test finished. 100 101-i:: 102--immediate:: 103 This causes the test to immediately exit upon the first 104 failed test. Cleanup commands requested with 105 test_when_finished are not executed if the test failed, 106 in order to keep the state for inspection by the tester 107 to diagnose the bug. 108 109-l:: 110--long-tests:: 111 This causes additional long-running tests to be run (where 112 available), for more exhaustive testing. 113 114-r:: 115--run=<test-selector>:: 116 Run only the subset of tests indicated by 117 <test-selector>. See section "Skipping Tests" below for 118 <test-selector> syntax. 119 120--valgrind=<tool>:: 121 Execute all Git binaries under valgrind tool <tool> and exit 122 with status 126 on errors (just like regular tests, this will 123 only stop the test script when running under -i). 124 125 Since it makes no sense to run the tests with --valgrind and 126 not see any output, this option implies --verbose. For 127 convenience, it also implies --tee. 128 129 <tool> defaults to 'memcheck', just like valgrind itself. 130 Other particularly useful choices include 'helgrind' and 131 'drd', but you may use any tool recognized by your valgrind 132 installation. 133 134 As a special case, <tool> can be 'memcheck-fast', which uses 135 memcheck but disables --track-origins. Use this if you are 136 running tests in bulk, to see if there are _any_ memory 137 issues. 138 139 Note that memcheck is run with the option --leak-check=no, 140 as the git process is short-lived and some errors are not 141 interesting. In order to run a single command under the same 142 conditions manually, you should set GIT_VALGRIND to point to 143 the 't/valgrind/' directory and use the commands under 144 't/valgrind/bin/'. 145 146--valgrind-only=<pattern>:: 147 Like --valgrind, but the effect is limited to tests with 148 numbers matching <pattern>. The number matched against is 149 simply the running count of the test within the file. 150 151--tee:: 152 In addition to printing the test output to the terminal, 153 write it to files named 't/test-results/$TEST_NAME.out'. 154 As the names depend on the tests' file names, it is safe to 155 run the tests with this option in parallel. 156 157--verbose-log:: 158 Write verbose output to the same logfile as `--tee`, but do 159 _not_ write it to stdout. Unlike `--tee --verbose`, this option 160 is safe to use when stdout is being consumed by a TAP parser 161 like `prove`. Implies `--tee` and `--verbose`. 162 163--with-dashes:: 164 By default tests are run without dashed forms of 165 commands (like git-commit) in the PATH (it only uses 166 wrappers from ../bin-wrappers). Use this option to include 167 the build directory (..) in the PATH, which contains all 168 the dashed forms of commands. This option is currently 169 implied by other options like --valgrind and 170 GIT_TEST_INSTALLED. 171 172--root=<directory>:: 173 Create "trash" directories used to store all temporary data during 174 testing under <directory>, instead of the t/ directory. 175 Using this option with a RAM-based filesystem (such as tmpfs) 176 can massively speed up the test suite. 177 178--chain-lint:: 179--no-chain-lint:: 180 If --chain-lint is enabled, the test harness will check each 181 test to make sure that it properly "&&-chains" all commands (so 182 that a failure in the middle does not go unnoticed by the final 183 exit code of the test). This check is performed in addition to 184 running the tests themselves. You may also enable or disable 185 this feature by setting the GIT_TEST_CHAIN_LINT environment 186 variable to "1" or "0", respectively. 187 188You can also set the GIT_TEST_INSTALLED environment variable to 189the bindir of an existing git installation to test that installation. 190You still need to have built this git sandbox, from which various 191test-* support programs, templates, and perl libraries are used. 192If your installed git is incomplete, it will silently test parts of 193your built version instead. 194 195When using GIT_TEST_INSTALLED, you can also set GIT_TEST_EXEC_PATH to 196override the location of the dashed-form subcommands (what 197GIT_EXEC_PATH would be used for during normal operation). 198GIT_TEST_EXEC_PATH defaults to `$GIT_TEST_INSTALLED/git --exec-path`. 199 200 201Skipping Tests 202-------------- 203 204In some environments, certain tests have no way of succeeding 205due to platform limitation, such as lack of 'unzip' program, or 206filesystem that do not allow arbitrary sequence of non-NUL bytes 207as pathnames. 208 209You should be able to say something like 210 211 $ GIT_SKIP_TESTS=t9200.8 sh ./t9200-git-cvsexport-commit.sh 212 213and even: 214 215 $ GIT_SKIP_TESTS='t[0-4]??? t91?? t9200.8' make 216 217to omit such tests. The value of the environment variable is a 218SP separated list of patterns that tells which tests to skip, 219and either can match the "t[0-9]{4}" part to skip the whole 220test, or t[0-9]{4} followed by ".$number" to say which 221particular test to skip. 222 223For an individual test suite --run could be used to specify that 224only some tests should be run or that some tests should be 225excluded from a run. 226 227The argument for --run is a list of individual test numbers or 228ranges with an optional negation prefix that define what tests in 229a test suite to include in the run. A range is two numbers 230separated with a dash and matches a range of tests with both ends 231been included. You may omit the first or the second number to 232mean "from the first test" or "up to the very last test" 233respectively. 234 235Optional prefix of '!' means that the test or a range of tests 236should be excluded from the run. 237 238If --run starts with an unprefixed number or range the initial 239set of tests to run is empty. If the first item starts with '!' 240all the tests are added to the initial set. After initial set is 241determined every test number or range is added or excluded from 242the set one by one, from left to right. 243 244Individual numbers or ranges could be separated either by a space 245or a comma. 246 247For example, to run only tests up to a specific test (21), one 248could do this: 249 250 $ sh ./t9200-git-cvsexport-commit.sh --run='1-21' 251 252or this: 253 254 $ sh ./t9200-git-cvsexport-commit.sh --run='-21' 255 256Common case is to run several setup tests (1, 2, 3) and then a 257specific test (21) that relies on that setup: 258 259 $ sh ./t9200-git-cvsexport-commit.sh --run='1 2 3 21' 260 261or: 262 263 $ sh ./t9200-git-cvsexport-commit.sh --run=1,2,3,21 264 265or: 266 267 $ sh ./t9200-git-cvsexport-commit.sh --run='-3 21' 268 269As noted above, the test set is built by going through the items 270from left to right, so this: 271 272 $ sh ./t9200-git-cvsexport-commit.sh --run='1-4 !3' 273 274will run tests 1, 2, and 4. Items that come later have higher 275precedence. It means that this: 276 277 $ sh ./t9200-git-cvsexport-commit.sh --run='!3 1-4' 278 279would just run tests from 1 to 4, including 3. 280 281You may use negation with ranges. The following will run all 282test in the test suite except from 7 up to 11: 283 284 $ sh ./t9200-git-cvsexport-commit.sh --run='!7-11' 285 286Some tests in a test suite rely on the previous tests performing 287certain actions, specifically some tests are designated as 288"setup" test, so you cannot _arbitrarily_ disable one test and 289expect the rest to function correctly. 290 291--run is mostly useful when you want to focus on a specific test 292and know what setup is needed for it. Or when you want to run 293everything up to a certain test. 294 295 296Running tests with special setups 297--------------------------------- 298 299The whole test suite could be run to test some special features 300that cannot be easily covered by a few specific test cases. These 301could be enabled by running the test suite with correct GIT_TEST_ 302environment set. 303 304GIT_TEST_GETTEXT_POISON=<non-empty?> turns all strings marked for 305translation into gibberish if non-empty (think "test -n"). Used for 306spotting those tests that need to be marked with a C_LOCALE_OUTPUT 307prerequisite when adding more strings for translation. See "Testing 308marked strings" in po/README for details. 309 310GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole 311test suite. Accept any boolean values that are accepted by git-config. 312 313GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon 314pack-objects code path where there are more than 1024 packs even if 315the actual number of packs in repository is below this limit. Accept 316any boolean values that are accepted by git-config. 317 318GIT_TEST_OE_SIZE=<n> exercises the uncommon pack-objects code path 319where we do not cache object size in memory and read it from existing 320packs on demand. This normally only happens when the object size is 321over 2GB. This variable forces the code path on any object larger than 322<n> bytes. 323 324GIT_TEST_OE_DELTA_SIZE=<n> exercises the uncommon pack-objects code 325path where deltas larger than this limit require extra memory 326allocation for bookkeeping. 327 328GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES=<boolean> checks that cache-tree 329records are valid when the index is written out or after a merge. This 330is mostly to catch missing invalidation. Default is true. 331 332GIT_TEST_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to 333be written after every 'git commit' command, and overrides the 334'core.commitGraph' setting to true. 335 336GIT_TEST_FSMONITOR=$PWD/t7519/fsmonitor-all exercises the fsmonitor 337code path for utilizing a file system monitor to speed up detecting 338new or changed files. 339 340GIT_TEST_INDEX_VERSION=<n> exercises the index read/write code path 341for the index version specified. Can be set to any valid version 342(currently 2, 3, or 4). 343 344GIT_TEST_PRELOAD_INDEX=<boolean> exercises the preload-index code path 345by overriding the minimum number of cache entries required per thread. 346 347GIT_TEST_INDEX_THREADS=<n> enables exercising the multi-threaded loading 348of the index for the whole test suite by bypassing the default number of 349cache entries and thread minimums. Setting this to 1 will make the 350index loading single threaded. 351 352Naming Tests 353------------ 354 355The test files are named as: 356 357 tNNNN-commandname-details.sh 358 359where N is a decimal digit. 360 361First digit tells the family: 362 363 0 - the absolute basics and global stuff 364 1 - the basic commands concerning database 365 2 - the basic commands concerning the working tree 366 3 - the other basic commands (e.g. ls-files) 367 4 - the diff commands 368 5 - the pull and exporting commands 369 6 - the revision tree commands (even e.g. merge-base) 370 7 - the porcelainish commands concerning the working tree 371 8 - the porcelainish commands concerning forensics 372 9 - the git tools 373 374Second digit tells the particular command we are testing. 375 376Third digit (optionally) tells the particular switch or group of switches 377we are testing. 378 379If you create files under t/ directory (i.e. here) that is not 380the top-level test script, never name the file to match the above 381pattern. The Makefile here considers all such files as the 382top-level test script and tries to run all of them. Care is 383especially needed if you are creating a common test library 384file, similar to test-lib.sh, because such a library file may 385not be suitable for standalone execution. 386 387 388Writing Tests 389------------- 390 391The test script is written as a shell script. It should start 392with the standard "#!/bin/sh", and an 393assignment to variable 'test_description', like this: 394 395 #!/bin/sh 396 397 test_description='xxx test (option --frotz) 398 399 This test registers the following structure in the cache 400 and tries to run git-ls-files with option --frotz.' 401 402 403Source 'test-lib.sh' 404-------------------- 405 406After assigning test_description, the test script should source 407test-lib.sh like this: 408 409 . ./test-lib.sh 410 411This test harness library does the following things: 412 413 - If the script is invoked with command line argument --help 414 (or -h), it shows the test_description and exits. 415 416 - Creates an empty test directory with an empty .git/objects database 417 and chdir(2) into it. This directory is 't/trash 418 directory.$test_name_without_dotsh', with t/ subject to change by 419 the --root option documented above. 420 421 - Defines standard test helper functions for your scripts to 422 use. These functions are designed to make all scripts behave 423 consistently when command line arguments --verbose (or -v), 424 --debug (or -d), and --immediate (or -i) is given. 425 426Do's & don'ts 427------------- 428 429Here are a few examples of things you probably should and shouldn't do 430when writing tests. 431 432Here are the "do's:" 433 434 - Put all code inside test_expect_success and other assertions. 435 436 Even code that isn't a test per se, but merely some setup code 437 should be inside a test assertion. 438 439 - Chain your test assertions 440 441 Write test code like this: 442 443 git merge foo && 444 git push bar && 445 test ... 446 447 Instead of: 448 449 git merge hla 450 git push gh 451 test ... 452 453 That way all of the commands in your tests will succeed or fail. If 454 you must ignore the return value of something, consider using a 455 helper function (e.g. use sane_unset instead of unset, in order 456 to avoid unportable return value for unsetting a variable that was 457 already unset), or prepending the command with test_might_fail or 458 test_must_fail. 459 460 - Check the test coverage for your tests. See the "Test coverage" 461 below. 462 463 Don't blindly follow test coverage metrics; if a new function you added 464 doesn't have any coverage, then you're probably doing something wrong, 465 but having 100% coverage doesn't necessarily mean that you tested 466 everything. 467 468 Tests that are likely to smoke out future regressions are better 469 than tests that just inflate the coverage metrics. 470 471 - When a test checks for an absolute path that a git command generated, 472 construct the expected value using $(pwd) rather than $PWD, 473 $TEST_DIRECTORY, or $TRASH_DIRECTORY. It makes a difference on 474 Windows, where the shell (MSYS bash) mangles absolute path names. 475 For details, see the commit message of 4114156ae9. 476 477 - Remember that inside the <script> part, the standard output and 478 standard error streams are discarded, and the test harness only 479 reports "ok" or "not ok" to the end user running the tests. Under 480 --verbose, they are shown to help debug the tests. 481 482And here are the "don'ts:" 483 484 - Don't exit() within a <script> part. 485 486 The harness will catch this as a programming error of the test. 487 Use test_done instead if you need to stop the tests early (see 488 "Skipping tests" below). 489 490 - Don't use '! git cmd' when you want to make sure the git command 491 exits with failure in a controlled way by calling "die()". Instead, 492 use 'test_must_fail git cmd'. This will signal a failure if git 493 dies in an unexpected way (e.g. segfault). 494 495 On the other hand, don't use test_must_fail for running regular 496 platform commands; just use '! cmd'. We are not in the business 497 of verifying that the world given to us sanely works. 498 499 - Don't feed the output of a git command to a pipe, as in: 500 501 git -C repo ls-files | 502 xargs -n 1 basename | 503 grep foo 504 505 which will discard git's exit code and may mask a crash. In the 506 above example, all exit codes are ignored except grep's. 507 508 Instead, write the output of that command to a temporary 509 file with ">" or assign it to a variable with "x=$(git ...)" rather 510 than pipe it. 511 512 - Don't use command substitution in a way that discards git's exit 513 code. When assigning to a variable, the exit code is not discarded, 514 e.g.: 515 516 x=$(git cat-file -p $sha) && 517 ... 518 519 is OK because a crash in "git cat-file" will cause the "&&" chain 520 to fail, but: 521 522 test "refs/heads/foo" = "$(git symbolic-ref HEAD)" 523 524 is not OK and a crash in git could go undetected. 525 526 - Don't use perl without spelling it as "$PERL_PATH". This is to help 527 our friends on Windows where the platform Perl often adds CR before 528 the end of line, and they bundle Git with a version of Perl that 529 does not do so, whose path is specified with $PERL_PATH. Note that we 530 provide a "perl" function which uses $PERL_PATH under the hood, so 531 you do not need to worry when simply running perl in the test scripts 532 (but you do, for example, on a shebang line or in a sub script 533 created via "write_script"). 534 535 - Don't use sh without spelling it as "$SHELL_PATH", when the script 536 can be misinterpreted by broken platform shell (e.g. Solaris). 537 538 - Don't chdir around in tests. It is not sufficient to chdir to 539 somewhere and then chdir back to the original location later in 540 the test, as any intermediate step can fail and abort the test, 541 causing the next test to start in an unexpected directory. Do so 542 inside a subshell if necessary. 543 544 - Don't save and verify the standard error of compound commands, i.e. 545 group commands, subshells, and shell functions (except test helper 546 functions like 'test_must_fail') like this: 547 548 ( cd dir && git cmd ) 2>error && 549 test_cmp expect error 550 551 When running the test with '-x' tracing, then the trace of commands 552 executed in the compound command will be included in standard error 553 as well, quite possibly throwing off the subsequent checks examining 554 the output. Instead, save only the relevant git command's standard 555 error: 556 557 ( cd dir && git cmd 2>../error ) && 558 test_cmp expect error 559 560 - Don't break the TAP output 561 562 The raw output from your test may be interpreted by a TAP harness. TAP 563 harnesses will ignore everything they don't know about, but don't step 564 on their toes in these areas: 565 566 - Don't print lines like "$x..$y" where $x and $y are integers. 567 568 - Don't print lines that begin with "ok" or "not ok". 569 570 TAP harnesses expect a line that begins with either "ok" and "not 571 ok" to signal a test passed or failed (and our harness already 572 produces such lines), so your script shouldn't emit such lines to 573 their output. 574 575 You can glean some further possible issues from the TAP grammar 576 (see https://metacpan.org/pod/TAP::Parser::Grammar#TAP-GRAMMAR) 577 but the best indication is to just run the tests with prove(1), 578 it'll complain if anything is amiss. 579 580 581Skipping tests 582-------------- 583 584If you need to skip tests you should do so by using the three-arg form 585of the test_* functions (see the "Test harness library" section 586below), e.g.: 587 588 test_expect_success PERL 'I need Perl' ' 589 perl -e "hlagh() if unf_unf()" 590 ' 591 592The advantage of skipping tests like this is that platforms that don't 593have the PERL and other optional dependencies get an indication of how 594many tests they're missing. 595 596If the test code is too hairy for that (i.e. does a lot of setup work 597outside test assertions) you can also skip all remaining tests by 598setting skip_all and immediately call test_done: 599 600 if ! test_have_prereq PERL 601 then 602 skip_all='skipping perl interface tests, perl not available' 603 test_done 604 fi 605 606The string you give to skip_all will be used as an explanation for why 607the test was skipped. 608 609End with test_done 610------------------ 611 612Your script will be a sequence of tests, using helper functions 613from the test harness library. At the end of the script, call 614'test_done'. 615 616 617Test harness library 618-------------------- 619 620There are a handful helper functions defined in the test harness 621library for your script to use. 622 623 - test_expect_success [<prereq>] <message> <script> 624 625 Usually takes two strings as parameters, and evaluates the 626 <script>. If it yields success, test is considered 627 successful. <message> should state what it is testing. 628 629 Example: 630 631 test_expect_success \ 632 'git-write-tree should be able to write an empty tree.' \ 633 'tree=$(git-write-tree)' 634 635 If you supply three parameters the first will be taken to be a 636 prerequisite; see the test_set_prereq and test_have_prereq 637 documentation below: 638 639 test_expect_success TTY 'git --paginate rev-list uses a pager' \ 640 ' ... ' 641 642 You can also supply a comma-separated list of prerequisites, in the 643 rare case where your test depends on more than one: 644 645 test_expect_success PERL,PYTHON 'yo dawg' \ 646 ' test $(perl -E 'print eval "1 +" . qx[python -c "print 2"]') == "4" ' 647 648 - test_expect_failure [<prereq>] <message> <script> 649 650 This is NOT the opposite of test_expect_success, but is used 651 to mark a test that demonstrates a known breakage. Unlike 652 the usual test_expect_success tests, which say "ok" on 653 success and "FAIL" on failure, this will say "FIXED" on 654 success and "still broken" on failure. Failures from these 655 tests won't cause -i (immediate) to stop. 656 657 Like test_expect_success this function can optionally use a three 658 argument invocation with a prerequisite as the first argument. 659 660 - test_debug <script> 661 662 This takes a single argument, <script>, and evaluates it only 663 when the test script is started with --debug command line 664 argument. This is primarily meant for use during the 665 development of a new test script. 666 667 - debug <git-command> 668 669 Run a git command inside a debugger. This is primarily meant for 670 use when debugging a failing test script. 671 672 - test_done 673 674 Your test script must have test_done at the end. Its purpose 675 is to summarize successes and failures in the test script and 676 exit with an appropriate error code. 677 678 - test_tick 679 680 Make commit and tag names consistent by setting the author and 681 committer times to defined state. Subsequent calls will 682 advance the times by a fixed amount. 683 684 - test_commit <message> [<filename> [<contents>]] 685 686 Creates a commit with the given message, committing the given 687 file with the given contents (default for both is to reuse the 688 message string), and adds a tag (again reusing the message 689 string as name). Calls test_tick to make the SHA-1s 690 reproducible. 691 692 - test_merge <message> <commit-or-tag> 693 694 Merges the given rev using the given message. Like test_commit, 695 creates a tag and calls test_tick before committing. 696 697 - test_set_prereq <prereq> 698 699 Set a test prerequisite to be used later with test_have_prereq. The 700 test-lib will set some prerequisites for you, see the 701 "Prerequisites" section below for a full list of these. 702 703 Others you can set yourself and use later with either 704 test_have_prereq directly, or the three argument invocation of 705 test_expect_success and test_expect_failure. 706 707 - test_have_prereq <prereq> 708 709 Check if we have a prerequisite previously set with test_set_prereq. 710 The most common way to use this explicitly (as opposed to the 711 implicit use when an argument is passed to test_expect_*) is to skip 712 all the tests at the start of the test script if we don't have some 713 essential prerequisite: 714 715 if ! test_have_prereq PERL 716 then 717 skip_all='skipping perl interface tests, perl not available' 718 test_done 719 fi 720 721 - test_external [<prereq>] <message> <external> <script> 722 723 Execute a <script> with an <external> interpreter (like perl). This 724 was added for tests like t9700-perl-git.sh which do most of their 725 work in an external test script. 726 727 test_external \ 728 'GitwebCache::*FileCache*' \ 729 perl "$TEST_DIRECTORY"/t9503/test_cache_interface.pl 730 731 If the test is outputting its own TAP you should set the 732 test_external_has_tap variable somewhere before calling the first 733 test_external* function. See t9700-perl-git.sh for an example. 734 735 # The external test will outputs its own plan 736 test_external_has_tap=1 737 738 - test_external_without_stderr [<prereq>] <message> <external> <script> 739 740 Like test_external but fail if there's any output on stderr, 741 instead of checking the exit code. 742 743 test_external_without_stderr \ 744 'Perl API' \ 745 perl "$TEST_DIRECTORY"/t9700/test.pl 746 747 - test_expect_code <exit-code> <command> 748 749 Run a command and ensure that it exits with the given exit code. 750 For example: 751 752 test_expect_success 'Merge with d/f conflicts' ' 753 test_expect_code 1 git merge "merge msg" B master 754 ' 755 756 - test_must_fail [<options>] <git-command> 757 758 Run a git command and ensure it fails in a controlled way. Use 759 this instead of "! <git-command>". When git-command dies due to a 760 segfault, test_must_fail diagnoses it as an error; "! <git-command>" 761 treats it as just another expected failure, which would let such a 762 bug go unnoticed. 763 764 Accepts the following options: 765 766 ok=<signal-name>[,<...>]: 767 Don't treat an exit caused by the given signal as error. 768 Multiple signals can be specified as a comma separated list. 769 Currently recognized signal names are: sigpipe, success. 770 (Don't use 'success', use 'test_might_fail' instead.) 771 772 - test_might_fail [<options>] <git-command> 773 774 Similar to test_must_fail, but tolerate success, too. Use this 775 instead of "<git-command> || :" to catch failures due to segv. 776 777 Accepts the same options as test_must_fail. 778 779 - test_cmp <expected> <actual> 780 781 Check whether the content of the <actual> file matches the 782 <expected> file. This behaves like "cmp" but produces more 783 helpful output when the test is run with "-v" option. 784 785 - test_cmp_rev <expected> <actual> 786 787 Check whether the <expected> rev points to the same commit as the 788 <actual> rev. 789 790 - test_line_count (= | -lt | -ge | ...) <length> <file> 791 792 Check whether a file has the length it is expected to. 793 794 - test_path_is_file <path> [<diagnosis>] 795 test_path_is_dir <path> [<diagnosis>] 796 test_path_is_missing <path> [<diagnosis>] 797 798 Check if the named path is a file, if the named path is a 799 directory, or if the named path does not exist, respectively, 800 and fail otherwise, showing the <diagnosis> text. 801 802 - test_when_finished <script> 803 804 Prepend <script> to a list of commands to run to clean up 805 at the end of the current test. If some clean-up command 806 fails, the test will not pass. 807 808 Example: 809 810 test_expect_success 'branch pointing to non-commit' ' 811 git rev-parse HEAD^{tree} >.git/refs/heads/invalid && 812 test_when_finished "git update-ref -d refs/heads/invalid" && 813 ... 814 ' 815 816 - test_write_lines <lines> 817 818 Write <lines> on standard output, one line per argument. 819 Useful to prepare multi-line files in a compact form. 820 821 Example: 822 823 test_write_lines a b c d e f g >foo 824 825 Is a more compact equivalent of: 826 cat >foo <<-EOF 827 a 828 b 829 c 830 d 831 e 832 f 833 g 834 EOF 835 836 837 - test_pause 838 839 This command is useful for writing and debugging tests and must be 840 removed before submitting. It halts the execution of the test and 841 spawns a shell in the trash directory. Exit the shell to continue 842 the test. Example: 843 844 test_expect_success 'test' ' 845 git do-something >actual && 846 test_pause && 847 test_cmp expected actual 848 ' 849 850 - test_ln_s_add <path1> <path2> 851 852 This function helps systems whose filesystem does not support symbolic 853 links. Use it to add a symbolic link entry to the index when it is not 854 important that the file system entry is a symbolic link, i.e., instead 855 of the sequence 856 857 ln -s foo bar && 858 git add bar 859 860 Sometimes it is possible to split a test in a part that does not need 861 the symbolic link in the file system and a part that does; then only 862 the latter part need be protected by a SYMLINKS prerequisite (see below). 863 864 - test_oid_init 865 866 This function loads facts and useful object IDs related to the hash 867 algorithm(s) in use from the files in t/oid-info. 868 869 - test_oid_cache 870 871 This function reads per-hash algorithm information from standard 872 input (usually a heredoc) in the format described in 873 t/oid-info/README. This is useful for test-specific values, such as 874 object IDs, which must vary based on the hash algorithm. 875 876 Certain fixed values, such as hash sizes and common placeholder 877 object IDs, can be loaded with test_oid_init (described above). 878 879 - test_oid <key> 880 881 This function looks up a value for the hash algorithm in use, based 882 on the key given. The value must have been loaded using 883 test_oid_init or test_oid_cache. Providing an unknown key is an 884 error. 885 886Prerequisites 887------------- 888 889These are the prerequisites that the test library predefines with 890test_have_prereq. 891 892See the prereq argument to the test_* functions in the "Test harness 893library" section above and the "test_have_prereq" function for how to 894use these, and "test_set_prereq" for how to define your own. 895 896 - PYTHON 897 898 Git wasn't compiled with NO_PYTHON=YesPlease. Wrap any tests that 899 need Python with this. 900 901 - PERL 902 903 Git wasn't compiled with NO_PERL=YesPlease. 904 905 Even without the PERL prerequisite, tests can assume there is a 906 usable perl interpreter at $PERL_PATH, though it need not be 907 particularly modern. 908 909 - POSIXPERM 910 911 The filesystem supports POSIX style permission bits. 912 913 - BSLASHPSPEC 914 915 Backslashes in pathspec are not directory separators. This is not 916 set on Windows. See 6fd1106a for details. 917 918 - EXECKEEPSPID 919 920 The process retains the same pid across exec(2). See fb9a2bea for 921 details. 922 923 - PIPE 924 925 The filesystem we're on supports creation of FIFOs (named pipes) 926 via mkfifo(1). 927 928 - SYMLINKS 929 930 The filesystem we're on supports symbolic links. E.g. a FAT 931 filesystem doesn't support these. See 704a3143 for details. 932 933 - SANITY 934 935 Test is not run by root user, and an attempt to write to an 936 unwritable file is expected to fail correctly. 937 938 - PCRE 939 940 Git was compiled with support for PCRE. Wrap any tests 941 that use git-grep --perl-regexp or git-grep -P in these. 942 943 - LIBPCRE1 944 945 Git was compiled with PCRE v1 support via 946 USE_LIBPCRE1=YesPlease. Wrap any PCRE using tests that for some 947 reason need v1 of the PCRE library instead of v2 in these. 948 949 - LIBPCRE2 950 951 Git was compiled with PCRE v2 support via 952 USE_LIBPCRE2=YesPlease. Wrap any PCRE using tests that for some 953 reason need v2 of the PCRE library instead of v1 in these. 954 955 - CASE_INSENSITIVE_FS 956 957 Test is run on a case insensitive file system. 958 959 - UTF8_NFD_TO_NFC 960 961 Test is run on a filesystem which converts decomposed utf-8 (nfd) 962 to precomposed utf-8 (nfc). 963 964 - PTHREADS 965 966 Git wasn't compiled with NO_PTHREADS=YesPlease. 967 968Tips for Writing Tests 969---------------------- 970 971As with any programming projects, existing programs are the best 972source of the information. However, do _not_ emulate 973t0000-basic.sh when writing your tests. The test is special in 974that it tries to validate the very core of GIT. For example, it 975knows that there will be 256 subdirectories under .git/objects/, 976and it knows that the object ID of an empty tree is a certain 97740-byte string. This is deliberately done so in t0000-basic.sh 978because the things the very basic core test tries to achieve is 979to serve as a basis for people who are changing the GIT internal 980drastically. For these people, after making certain changes, 981not seeing failures from the basic test _is_ a failure. And 982such drastic changes to the core GIT that even changes these 983otherwise supposedly stable object IDs should be accompanied by 984an update to t0000-basic.sh. 985 986However, other tests that simply rely on basic parts of the core 987GIT working properly should not have that level of intimate 988knowledge of the core GIT internals. If all the test scripts 989hardcoded the object IDs like t0000-basic.sh does, that defeats 990the purpose of t0000-basic.sh, which is to isolate that level of 991validation in one place. Your test also ends up needing 992updating when such a change to the internal happens, so do _not_ 993do it and leave the low level of validation to t0000-basic.sh. 994 995Test coverage 996------------- 997 998You can use the coverage tests to find code paths that are not being 999used or properly exercised yet.10001001To do that, run the coverage target at the top-level (not in the t/1002directory):10031004 make coverage10051006That'll compile Git with GCC's coverage arguments, and generate a test1007report with gcov after the tests finish. Running the coverage tests1008can take a while, since running the tests in parallel is incompatible1009with GCC's coverage mode.10101011After the tests have run you can generate a list of untested1012functions:10131014 make coverage-untested-functions10151016You can also generate a detailed per-file HTML report using the1017Devel::Cover module. To install it do:10181019 # On Debian or Ubuntu:1020 sudo aptitude install libdevel-cover-perl10211022 # From the CPAN with cpanminus1023 curl -L http://cpanmin.us | perl - --sudo --self-upgrade1024 cpanm --sudo Devel::Cover10251026Then, at the top-level:10271028 make cover_db_html10291030That'll generate a detailed cover report in the "cover_db_html"1031directory, which you can then copy to a webserver, or inspect locally1032in a browser.