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_SPLIT_INDEX=<boolean> forces split-index mode on the whole 305test suite. Accept any boolean values that are accepted by git-config. 306 307GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon 308pack-objects code path where there are more than 1024 packs even if 309the actual number of packs in repository is below this limit. Accept 310any boolean values that are accepted by git-config. 311 312GIT_TEST_OE_SIZE=<n> exercises the uncommon pack-objects code path 313where we do not cache object size in memory and read it from existing 314packs on demand. This normally only happens when the object size is 315over 2GB. This variable forces the code path on any object larger than 316<n> bytes. 317 318GIT_TEST_OE_DELTA_SIZE=<n> exercises the uncomon pack-objects code 319path where deltas larger than this limit require extra memory 320allocation for bookkeeping. 321 322GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES=<boolean> checks that cache-tree 323records are valid when the index is written out or after a merge. This 324is mostly to catch missing invalidation. Default is true. 325 326GIT_TEST_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to 327be written after every 'git commit' command, and overrides the 328'core.commitGraph' setting to true. 329 330Naming Tests 331------------ 332 333The test files are named as: 334 335 tNNNN-commandname-details.sh 336 337where N is a decimal digit. 338 339First digit tells the family: 340 341 0 - the absolute basics and global stuff 342 1 - the basic commands concerning database 343 2 - the basic commands concerning the working tree 344 3 - the other basic commands (e.g. ls-files) 345 4 - the diff commands 346 5 - the pull and exporting commands 347 6 - the revision tree commands (even e.g. merge-base) 348 7 - the porcelainish commands concerning the working tree 349 8 - the porcelainish commands concerning forensics 350 9 - the git tools 351 352Second digit tells the particular command we are testing. 353 354Third digit (optionally) tells the particular switch or group of switches 355we are testing. 356 357If you create files under t/ directory (i.e. here) that is not 358the top-level test script, never name the file to match the above 359pattern. The Makefile here considers all such files as the 360top-level test script and tries to run all of them. Care is 361especially needed if you are creating a common test library 362file, similar to test-lib.sh, because such a library file may 363not be suitable for standalone execution. 364 365 366Writing Tests 367------------- 368 369The test script is written as a shell script. It should start 370with the standard "#!/bin/sh", and an 371assignment to variable 'test_description', like this: 372 373 #!/bin/sh 374 375 test_description='xxx test (option --frotz) 376 377 This test registers the following structure in the cache 378 and tries to run git-ls-files with option --frotz.' 379 380 381Source 'test-lib.sh' 382-------------------- 383 384After assigning test_description, the test script should source 385test-lib.sh like this: 386 387 . ./test-lib.sh 388 389This test harness library does the following things: 390 391 - If the script is invoked with command line argument --help 392 (or -h), it shows the test_description and exits. 393 394 - Creates an empty test directory with an empty .git/objects database 395 and chdir(2) into it. This directory is 't/trash 396 directory.$test_name_without_dotsh', with t/ subject to change by 397 the --root option documented above. 398 399 - Defines standard test helper functions for your scripts to 400 use. These functions are designed to make all scripts behave 401 consistently when command line arguments --verbose (or -v), 402 --debug (or -d), and --immediate (or -i) is given. 403 404Do's & don'ts 405------------- 406 407Here are a few examples of things you probably should and shouldn't do 408when writing tests. 409 410Here are the "do's:" 411 412 - Put all code inside test_expect_success and other assertions. 413 414 Even code that isn't a test per se, but merely some setup code 415 should be inside a test assertion. 416 417 - Chain your test assertions 418 419 Write test code like this: 420 421 git merge foo && 422 git push bar && 423 test ... 424 425 Instead of: 426 427 git merge hla 428 git push gh 429 test ... 430 431 That way all of the commands in your tests will succeed or fail. If 432 you must ignore the return value of something, consider using a 433 helper function (e.g. use sane_unset instead of unset, in order 434 to avoid unportable return value for unsetting a variable that was 435 already unset), or prepending the command with test_might_fail or 436 test_must_fail. 437 438 - Check the test coverage for your tests. See the "Test coverage" 439 below. 440 441 Don't blindly follow test coverage metrics; if a new function you added 442 doesn't have any coverage, then you're probably doing something wrong, 443 but having 100% coverage doesn't necessarily mean that you tested 444 everything. 445 446 Tests that are likely to smoke out future regressions are better 447 than tests that just inflate the coverage metrics. 448 449 - When a test checks for an absolute path that a git command generated, 450 construct the expected value using $(pwd) rather than $PWD, 451 $TEST_DIRECTORY, or $TRASH_DIRECTORY. It makes a difference on 452 Windows, where the shell (MSYS bash) mangles absolute path names. 453 For details, see the commit message of 4114156ae9. 454 455 - Remember that inside the <script> part, the standard output and 456 standard error streams are discarded, and the test harness only 457 reports "ok" or "not ok" to the end user running the tests. Under 458 --verbose, they are shown to help debug the tests. 459 460And here are the "don'ts:" 461 462 - Don't exit() within a <script> part. 463 464 The harness will catch this as a programming error of the test. 465 Use test_done instead if you need to stop the tests early (see 466 "Skipping tests" below). 467 468 - Don't use '! git cmd' when you want to make sure the git command 469 exits with failure in a controlled way by calling "die()". Instead, 470 use 'test_must_fail git cmd'. This will signal a failure if git 471 dies in an unexpected way (e.g. segfault). 472 473 On the other hand, don't use test_must_fail for running regular 474 platform commands; just use '! cmd'. We are not in the business 475 of verifying that the world given to us sanely works. 476 477 - Don't feed the output of a git command to a pipe, as in: 478 479 git -C repo ls-files | 480 xargs -n 1 basename | 481 grep foo 482 483 which will discard git's exit code and may mask a crash. In the 484 above example, all exit codes are ignored except grep's. 485 486 Instead, write the output of that command to a temporary 487 file with ">" or assign it to a variable with "x=$(git ...)" rather 488 than pipe it. 489 490 - Don't use command substitution in a way that discards git's exit 491 code. When assigning to a variable, the exit code is not discarded, 492 e.g.: 493 494 x=$(git cat-file -p $sha) && 495 ... 496 497 is OK because a crash in "git cat-file" will cause the "&&" chain 498 to fail, but: 499 500 test "refs/heads/foo" = "$(git symbolic-ref HEAD)" 501 502 is not OK and a crash in git could go undetected. 503 504 - Don't use perl without spelling it as "$PERL_PATH". This is to help 505 our friends on Windows where the platform Perl often adds CR before 506 the end of line, and they bundle Git with a version of Perl that 507 does not do so, whose path is specified with $PERL_PATH. Note that we 508 provide a "perl" function which uses $PERL_PATH under the hood, so 509 you do not need to worry when simply running perl in the test scripts 510 (but you do, for example, on a shebang line or in a sub script 511 created via "write_script"). 512 513 - Don't use sh without spelling it as "$SHELL_PATH", when the script 514 can be misinterpreted by broken platform shell (e.g. Solaris). 515 516 - Don't chdir around in tests. It is not sufficient to chdir to 517 somewhere and then chdir back to the original location later in 518 the test, as any intermediate step can fail and abort the test, 519 causing the next test to start in an unexpected directory. Do so 520 inside a subshell if necessary. 521 522 - Don't save and verify the standard error of compound commands, i.e. 523 group commands, subshells, and shell functions (except test helper 524 functions like 'test_must_fail') like this: 525 526 ( cd dir && git cmd ) 2>error && 527 test_cmp expect error 528 529 When running the test with '-x' tracing, then the trace of commands 530 executed in the compound command will be included in standard error 531 as well, quite possibly throwing off the subsequent checks examining 532 the output. Instead, save only the relevant git command's standard 533 error: 534 535 ( cd dir && git cmd 2>../error ) && 536 test_cmp expect error 537 538 - Don't break the TAP output 539 540 The raw output from your test may be interpreted by a TAP harness. TAP 541 harnesses will ignore everything they don't know about, but don't step 542 on their toes in these areas: 543 544 - Don't print lines like "$x..$y" where $x and $y are integers. 545 546 - Don't print lines that begin with "ok" or "not ok". 547 548 TAP harnesses expect a line that begins with either "ok" and "not 549 ok" to signal a test passed or failed (and our harness already 550 produces such lines), so your script shouldn't emit such lines to 551 their output. 552 553 You can glean some further possible issues from the TAP grammar 554 (see https://metacpan.org/pod/TAP::Parser::Grammar#TAP-GRAMMAR) 555 but the best indication is to just run the tests with prove(1), 556 it'll complain if anything is amiss. 557 558 559Skipping tests 560-------------- 561 562If you need to skip tests you should do so by using the three-arg form 563of the test_* functions (see the "Test harness library" section 564below), e.g.: 565 566 test_expect_success PERL 'I need Perl' ' 567 perl -e "hlagh() if unf_unf()" 568 ' 569 570The advantage of skipping tests like this is that platforms that don't 571have the PERL and other optional dependencies get an indication of how 572many tests they're missing. 573 574If the test code is too hairy for that (i.e. does a lot of setup work 575outside test assertions) you can also skip all remaining tests by 576setting skip_all and immediately call test_done: 577 578 if ! test_have_prereq PERL 579 then 580 skip_all='skipping perl interface tests, perl not available' 581 test_done 582 fi 583 584The string you give to skip_all will be used as an explanation for why 585the test was skipped. 586 587End with test_done 588------------------ 589 590Your script will be a sequence of tests, using helper functions 591from the test harness library. At the end of the script, call 592'test_done'. 593 594 595Test harness library 596-------------------- 597 598There are a handful helper functions defined in the test harness 599library for your script to use. 600 601 - test_expect_success [<prereq>] <message> <script> 602 603 Usually takes two strings as parameters, and evaluates the 604 <script>. If it yields success, test is considered 605 successful. <message> should state what it is testing. 606 607 Example: 608 609 test_expect_success \ 610 'git-write-tree should be able to write an empty tree.' \ 611 'tree=$(git-write-tree)' 612 613 If you supply three parameters the first will be taken to be a 614 prerequisite; see the test_set_prereq and test_have_prereq 615 documentation below: 616 617 test_expect_success TTY 'git --paginate rev-list uses a pager' \ 618 ' ... ' 619 620 You can also supply a comma-separated list of prerequisites, in the 621 rare case where your test depends on more than one: 622 623 test_expect_success PERL,PYTHON 'yo dawg' \ 624 ' test $(perl -E 'print eval "1 +" . qx[python -c "print 2"]') == "4" ' 625 626 - test_expect_failure [<prereq>] <message> <script> 627 628 This is NOT the opposite of test_expect_success, but is used 629 to mark a test that demonstrates a known breakage. Unlike 630 the usual test_expect_success tests, which say "ok" on 631 success and "FAIL" on failure, this will say "FIXED" on 632 success and "still broken" on failure. Failures from these 633 tests won't cause -i (immediate) to stop. 634 635 Like test_expect_success this function can optionally use a three 636 argument invocation with a prerequisite as the first argument. 637 638 - test_debug <script> 639 640 This takes a single argument, <script>, and evaluates it only 641 when the test script is started with --debug command line 642 argument. This is primarily meant for use during the 643 development of a new test script. 644 645 - debug <git-command> 646 647 Run a git command inside a debugger. This is primarily meant for 648 use when debugging a failing test script. 649 650 - test_done 651 652 Your test script must have test_done at the end. Its purpose 653 is to summarize successes and failures in the test script and 654 exit with an appropriate error code. 655 656 - test_tick 657 658 Make commit and tag names consistent by setting the author and 659 committer times to defined state. Subsequent calls will 660 advance the times by a fixed amount. 661 662 - test_commit <message> [<filename> [<contents>]] 663 664 Creates a commit with the given message, committing the given 665 file with the given contents (default for both is to reuse the 666 message string), and adds a tag (again reusing the message 667 string as name). Calls test_tick to make the SHA-1s 668 reproducible. 669 670 - test_merge <message> <commit-or-tag> 671 672 Merges the given rev using the given message. Like test_commit, 673 creates a tag and calls test_tick before committing. 674 675 - test_set_prereq <prereq> 676 677 Set a test prerequisite to be used later with test_have_prereq. The 678 test-lib will set some prerequisites for you, see the 679 "Prerequisites" section below for a full list of these. 680 681 Others you can set yourself and use later with either 682 test_have_prereq directly, or the three argument invocation of 683 test_expect_success and test_expect_failure. 684 685 - test_have_prereq <prereq> 686 687 Check if we have a prerequisite previously set with test_set_prereq. 688 The most common way to use this explicitly (as opposed to the 689 implicit use when an argument is passed to test_expect_*) is to skip 690 all the tests at the start of the test script if we don't have some 691 essential prerequisite: 692 693 if ! test_have_prereq PERL 694 then 695 skip_all='skipping perl interface tests, perl not available' 696 test_done 697 fi 698 699 - test_external [<prereq>] <message> <external> <script> 700 701 Execute a <script> with an <external> interpreter (like perl). This 702 was added for tests like t9700-perl-git.sh which do most of their 703 work in an external test script. 704 705 test_external \ 706 'GitwebCache::*FileCache*' \ 707 perl "$TEST_DIRECTORY"/t9503/test_cache_interface.pl 708 709 If the test is outputting its own TAP you should set the 710 test_external_has_tap variable somewhere before calling the first 711 test_external* function. See t9700-perl-git.sh for an example. 712 713 # The external test will outputs its own plan 714 test_external_has_tap=1 715 716 - test_external_without_stderr [<prereq>] <message> <external> <script> 717 718 Like test_external but fail if there's any output on stderr, 719 instead of checking the exit code. 720 721 test_external_without_stderr \ 722 'Perl API' \ 723 perl "$TEST_DIRECTORY"/t9700/test.pl 724 725 - test_expect_code <exit-code> <command> 726 727 Run a command and ensure that it exits with the given exit code. 728 For example: 729 730 test_expect_success 'Merge with d/f conflicts' ' 731 test_expect_code 1 git merge "merge msg" B master 732 ' 733 734 - test_must_fail [<options>] <git-command> 735 736 Run a git command and ensure it fails in a controlled way. Use 737 this instead of "! <git-command>". When git-command dies due to a 738 segfault, test_must_fail diagnoses it as an error; "! <git-command>" 739 treats it as just another expected failure, which would let such a 740 bug go unnoticed. 741 742 Accepts the following options: 743 744 ok=<signal-name>[,<...>]: 745 Don't treat an exit caused by the given signal as error. 746 Multiple signals can be specified as a comma separated list. 747 Currently recognized signal names are: sigpipe, success. 748 (Don't use 'success', use 'test_might_fail' instead.) 749 750 - test_might_fail [<options>] <git-command> 751 752 Similar to test_must_fail, but tolerate success, too. Use this 753 instead of "<git-command> || :" to catch failures due to segv. 754 755 Accepts the same options as test_must_fail. 756 757 - test_cmp <expected> <actual> 758 759 Check whether the content of the <actual> file matches the 760 <expected> file. This behaves like "cmp" but produces more 761 helpful output when the test is run with "-v" option. 762 763 - test_cmp_rev <expected> <actual> 764 765 Check whether the <expected> rev points to the same commit as the 766 <actual> rev. 767 768 - test_line_count (= | -lt | -ge | ...) <length> <file> 769 770 Check whether a file has the length it is expected to. 771 772 - test_path_is_file <path> [<diagnosis>] 773 test_path_is_dir <path> [<diagnosis>] 774 test_path_is_missing <path> [<diagnosis>] 775 776 Check if the named path is a file, if the named path is a 777 directory, or if the named path does not exist, respectively, 778 and fail otherwise, showing the <diagnosis> text. 779 780 - test_when_finished <script> 781 782 Prepend <script> to a list of commands to run to clean up 783 at the end of the current test. If some clean-up command 784 fails, the test will not pass. 785 786 Example: 787 788 test_expect_success 'branch pointing to non-commit' ' 789 git rev-parse HEAD^{tree} >.git/refs/heads/invalid && 790 test_when_finished "git update-ref -d refs/heads/invalid" && 791 ... 792 ' 793 794 - test_write_lines <lines> 795 796 Write <lines> on standard output, one line per argument. 797 Useful to prepare multi-line files in a compact form. 798 799 Example: 800 801 test_write_lines a b c d e f g >foo 802 803 Is a more compact equivalent of: 804 cat >foo <<-EOF 805 a 806 b 807 c 808 d 809 e 810 f 811 g 812 EOF 813 814 815 - test_pause 816 817 This command is useful for writing and debugging tests and must be 818 removed before submitting. It halts the execution of the test and 819 spawns a shell in the trash directory. Exit the shell to continue 820 the test. Example: 821 822 test_expect_success 'test' ' 823 git do-something >actual && 824 test_pause && 825 test_cmp expected actual 826 ' 827 828 - test_ln_s_add <path1> <path2> 829 830 This function helps systems whose filesystem does not support symbolic 831 links. Use it to add a symbolic link entry to the index when it is not 832 important that the file system entry is a symbolic link, i.e., instead 833 of the sequence 834 835 ln -s foo bar && 836 git add bar 837 838 Sometimes it is possible to split a test in a part that does not need 839 the symbolic link in the file system and a part that does; then only 840 the latter part need be protected by a SYMLINKS prerequisite (see below). 841 842Prerequisites 843------------- 844 845These are the prerequisites that the test library predefines with 846test_have_prereq. 847 848See the prereq argument to the test_* functions in the "Test harness 849library" section above and the "test_have_prereq" function for how to 850use these, and "test_set_prereq" for how to define your own. 851 852 - PYTHON 853 854 Git wasn't compiled with NO_PYTHON=YesPlease. Wrap any tests that 855 need Python with this. 856 857 - PERL 858 859 Git wasn't compiled with NO_PERL=YesPlease. 860 861 Even without the PERL prerequisite, tests can assume there is a 862 usable perl interpreter at $PERL_PATH, though it need not be 863 particularly modern. 864 865 - POSIXPERM 866 867 The filesystem supports POSIX style permission bits. 868 869 - BSLASHPSPEC 870 871 Backslashes in pathspec are not directory separators. This is not 872 set on Windows. See 6fd1106a for details. 873 874 - EXECKEEPSPID 875 876 The process retains the same pid across exec(2). See fb9a2bea for 877 details. 878 879 - PIPE 880 881 The filesystem we're on supports creation of FIFOs (named pipes) 882 via mkfifo(1). 883 884 - SYMLINKS 885 886 The filesystem we're on supports symbolic links. E.g. a FAT 887 filesystem doesn't support these. See 704a3143 for details. 888 889 - SANITY 890 891 Test is not run by root user, and an attempt to write to an 892 unwritable file is expected to fail correctly. 893 894 - PCRE 895 896 Git was compiled with support for PCRE. Wrap any tests 897 that use git-grep --perl-regexp or git-grep -P in these. 898 899 - LIBPCRE1 900 901 Git was compiled with PCRE v1 support via 902 USE_LIBPCRE1=YesPlease. Wrap any PCRE using tests that for some 903 reason need v1 of the PCRE library instead of v2 in these. 904 905 - LIBPCRE2 906 907 Git was compiled with PCRE v2 support via 908 USE_LIBPCRE2=YesPlease. Wrap any PCRE using tests that for some 909 reason need v2 of the PCRE library instead of v1 in these. 910 911 - CASE_INSENSITIVE_FS 912 913 Test is run on a case insensitive file system. 914 915 - UTF8_NFD_TO_NFC 916 917 Test is run on a filesystem which converts decomposed utf-8 (nfd) 918 to precomposed utf-8 (nfc). 919 920 - PTHREADS 921 922 Git wasn't compiled with NO_PTHREADS=YesPlease. 923 924Tips for Writing Tests 925---------------------- 926 927As with any programming projects, existing programs are the best 928source of the information. However, do _not_ emulate 929t0000-basic.sh when writing your tests. The test is special in 930that it tries to validate the very core of GIT. For example, it 931knows that there will be 256 subdirectories under .git/objects/, 932and it knows that the object ID of an empty tree is a certain 93340-byte string. This is deliberately done so in t0000-basic.sh 934because the things the very basic core test tries to achieve is 935to serve as a basis for people who are changing the GIT internal 936drastically. For these people, after making certain changes, 937not seeing failures from the basic test _is_ a failure. And 938such drastic changes to the core GIT that even changes these 939otherwise supposedly stable object IDs should be accompanied by 940an update to t0000-basic.sh. 941 942However, other tests that simply rely on basic parts of the core 943GIT working properly should not have that level of intimate 944knowledge of the core GIT internals. If all the test scripts 945hardcoded the object IDs like t0000-basic.sh does, that defeats 946the purpose of t0000-basic.sh, which is to isolate that level of 947validation in one place. Your test also ends up needing 948updating when such a change to the internal happens, so do _not_ 949do it and leave the low level of validation to t0000-basic.sh. 950 951Test coverage 952------------- 953 954You can use the coverage tests to find code paths that are not being 955used or properly exercised yet. 956 957To do that, run the coverage target at the top-level (not in the t/ 958directory): 959 960 make coverage 961 962That'll compile Git with GCC's coverage arguments, and generate a test 963report with gcov after the tests finish. Running the coverage tests 964can take a while, since running the tests in parallel is incompatible 965with GCC's coverage mode. 966 967After the tests have run you can generate a list of untested 968functions: 969 970 make coverage-untested-functions 971 972You can also generate a detailed per-file HTML report using the 973Devel::Cover module. To install it do: 974 975 # On Debian or Ubuntu: 976 sudo aptitude install libdevel-cover-perl 977 978 # From the CPAN with cpanminus 979 curl -L http://cpanmin.us | perl - --sudo --self-upgrade 980 cpanm --sudo Devel::Cover 981 982Then, at the top-level: 983 984 make cover_db_html 985 986That'll generate a detailed cover report in the "cover_db_html" 987directory, which you can then copy to a webserver, or inspect locally 988in a browser.