3ea6c854606056e1a7d9431dd59518d817768527
[git/git.git] / t / README
1 Core GIT Tests
2 ==============
3
4 This directory holds many test scripts for core GIT tools. The
5 first part of this short document describes how to run the tests
6 and read their output.
7
8 When fixing the tools or adding enhancements, you are strongly
9 encouraged to add tests in this directory to cover what you are
10 trying to fix or enhance. The later part of this short document
11 describes how your test scripts should be organized.
12
13
14 Running Tests
15 -------------
16
17 The easiest way to run tests is to say "make". This runs all
18 the 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
35 Since the tests all output TAP (see http://testanything.org) they can
36 be run with any TAP harness. Here's an example of parallel testing
37 powered 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
47 prove 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
53 You can give DEFAULT_TEST_TARGET=prove on the make command (or define it
54 in config.mak) to cause "make test" to run tests under prove.
55 GIT_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
59 You 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
70 You 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
72 appropriately 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
188 You can also set the GIT_TEST_INSTALLED environment variable to
189 the bindir of an existing git installation to test that installation.
190 You still need to have built this git sandbox, from which various
191 test-* support programs, templates, and perl libraries are used.
192 If your installed git is incomplete, it will silently test parts of
193 your built version instead.
194
195 When using GIT_TEST_INSTALLED, you can also set GIT_TEST_EXEC_PATH to
196 override the location of the dashed-form subcommands (what
197 GIT_EXEC_PATH would be used for during normal operation).
198 GIT_TEST_EXEC_PATH defaults to `$GIT_TEST_INSTALLED/git --exec-path`.
199
200
201 Skipping Tests
202 --------------
203
204 In some environments, certain tests have no way of succeeding
205 due to platform limitation, such as lack of 'unzip' program, or
206 filesystem that do not allow arbitrary sequence of non-NUL bytes
207 as pathnames.
208
209 You should be able to say something like
210
211 $ GIT_SKIP_TESTS=t9200.8 sh ./t9200-git-cvsexport-commit.sh
212
213 and even:
214
215 $ GIT_SKIP_TESTS='t[0-4]??? t91?? t9200.8' make
216
217 to omit such tests. The value of the environment variable is a
218 SP separated list of patterns that tells which tests to skip,
219 and either can match the "t[0-9]{4}" part to skip the whole
220 test, or t[0-9]{4} followed by ".$number" to say which
221 particular test to skip.
222
223 For an individual test suite --run could be used to specify that
224 only some tests should be run or that some tests should be
225 excluded from a run.
226
227 The argument for --run is a list of individual test numbers or
228 ranges with an optional negation prefix that define what tests in
229 a test suite to include in the run. A range is two numbers
230 separated with a dash and matches a range of tests with both ends
231 been included. You may omit the first or the second number to
232 mean "from the first test" or "up to the very last test"
233 respectively.
234
235 Optional prefix of '!' means that the test or a range of tests
236 should be excluded from the run.
237
238 If --run starts with an unprefixed number or range the initial
239 set of tests to run is empty. If the first item starts with '!'
240 all the tests are added to the initial set. After initial set is
241 determined every test number or range is added or excluded from
242 the set one by one, from left to right.
243
244 Individual numbers or ranges could be separated either by a space
245 or a comma.
246
247 For example, to run only tests up to a specific test (21), one
248 could do this:
249
250 $ sh ./t9200-git-cvsexport-commit.sh --run='1-21'
251
252 or this:
253
254 $ sh ./t9200-git-cvsexport-commit.sh --run='-21'
255
256 Common case is to run several setup tests (1, 2, 3) and then a
257 specific test (21) that relies on that setup:
258
259 $ sh ./t9200-git-cvsexport-commit.sh --run='1 2 3 21'
260
261 or:
262
263 $ sh ./t9200-git-cvsexport-commit.sh --run=1,2,3,21
264
265 or:
266
267 $ sh ./t9200-git-cvsexport-commit.sh --run='-3 21'
268
269 As noted above, the test set is built by going through the items
270 from left to right, so this:
271
272 $ sh ./t9200-git-cvsexport-commit.sh --run='1-4 !3'
273
274 will run tests 1, 2, and 4. Items that come later have higher
275 precedence. It means that this:
276
277 $ sh ./t9200-git-cvsexport-commit.sh --run='!3 1-4'
278
279 would just run tests from 1 to 4, including 3.
280
281 You may use negation with ranges. The following will run all
282 test in the test suite except from 7 up to 11:
283
284 $ sh ./t9200-git-cvsexport-commit.sh --run='!7-11'
285
286 Some tests in a test suite rely on the previous tests performing
287 certain actions, specifically some tests are designated as
288 "setup" test, so you cannot _arbitrarily_ disable one test and
289 expect the rest to function correctly.
290
291 --run is mostly useful when you want to focus on a specific test
292 and know what setup is needed for it. Or when you want to run
293 everything up to a certain test.
294
295
296 Running tests with special setups
297 ---------------------------------
298
299 The whole test suite could be run to test some special features
300 that cannot be easily covered by a few specific test cases. These
301 could be enabled by running the test suite with correct GIT_TEST_
302 environment set.
303
304 GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole
305 test suite. Accept any boolean values that are accepted by git-config.
306
307 GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon
308 pack-objects code path where there are more than 1024 packs even if
309 the actual number of packs in repository is below this limit. Accept
310 any boolean values that are accepted by git-config.
311
312 GIT_TEST_OE_SIZE=<n> exercises the uncommon pack-objects code path
313 where we do not cache object size in memory and read it from existing
314 packs on demand. This normally only happens when the object size is
315 over 2GB. This variable forces the code path on any object larger than
316 <n> bytes.
317
318 GIT_TEST_OE_DELTA_SIZE=<n> exercises the uncomon pack-objects code
319 path where deltas larger than this limit require extra memory
320 allocation for bookkeeping.
321
322 GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES=<boolean> checks that cache-tree
323 records are valid when the index is written out or after a merge. This
324 is mostly to catch missing invalidation. Default is true.
325
326 GIT_TEST_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to
327 be written after every 'git commit' command, and overrides the
328 'core.commitGraph' setting to true.
329
330 Naming Tests
331 ------------
332
333 The test files are named as:
334
335 tNNNN-commandname-details.sh
336
337 where N is a decimal digit.
338
339 First 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
352 Second digit tells the particular command we are testing.
353
354 Third digit (optionally) tells the particular switch or group of switches
355 we are testing.
356
357 If you create files under t/ directory (i.e. here) that is not
358 the top-level test script, never name the file to match the above
359 pattern. The Makefile here considers all such files as the
360 top-level test script and tries to run all of them. Care is
361 especially needed if you are creating a common test library
362 file, similar to test-lib.sh, because such a library file may
363 not be suitable for standalone execution.
364
365
366 Writing Tests
367 -------------
368
369 The test script is written as a shell script. It should start
370 with the standard "#!/bin/sh", and an
371 assignment 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
381 Source 'test-lib.sh'
382 --------------------
383
384 After assigning test_description, the test script should source
385 test-lib.sh like this:
386
387 . ./test-lib.sh
388
389 This 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
404 Do's, don'ts & things to keep in mind
405 -------------------------------------
406
407 Here are a few examples of things you probably should and shouldn't do
408 when writing tests.
409
410 Do:
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 $TRASH_DIRECTORY. It makes a difference on
452 Windows, where the shell (MSYS bash) mangles absolute path names.
453 For details, see the commit message of 4114156ae9.
454
455 Don't:
456
457 - exit() within a <script> part.
458
459 The harness will catch this as a programming error of the test.
460 Use test_done instead if you need to stop the tests early (see
461 "Skipping tests" below).
462
463 - use '! git cmd' when you want to make sure the git command exits
464 with failure in a controlled way by calling "die()". Instead,
465 use 'test_must_fail git cmd'. This will signal a failure if git
466 dies in an unexpected way (e.g. segfault).
467
468 On the other hand, don't use test_must_fail for running regular
469 platform commands; just use '! cmd'. We are not in the business
470 of verifying that the world given to us sanely works.
471
472 - use perl without spelling it as "$PERL_PATH". This is to help our
473 friends on Windows where the platform Perl often adds CR before
474 the end of line, and they bundle Git with a version of Perl that
475 does not do so, whose path is specified with $PERL_PATH. Note that we
476 provide a "perl" function which uses $PERL_PATH under the hood, so
477 you do not need to worry when simply running perl in the test scripts
478 (but you do, for example, on a shebang line or in a sub script
479 created via "write_script").
480
481 - use sh without spelling it as "$SHELL_PATH", when the script can
482 be misinterpreted by broken platform shell (e.g. Solaris).
483
484 - chdir around in tests. It is not sufficient to chdir to
485 somewhere and then chdir back to the original location later in
486 the test, as any intermediate step can fail and abort the test,
487 causing the next test to start in an unexpected directory. Do so
488 inside a subshell if necessary.
489
490 - save and verify the standard error of compound commands, i.e. group
491 commands, subshells, and shell functions (except test helper
492 functions like 'test_must_fail') like this:
493
494 ( cd dir && git cmd ) 2>error &&
495 test_cmp expect error
496
497 When running the test with '-x' tracing, then the trace of commands
498 executed in the compound command will be included in standard error
499 as well, quite possibly throwing off the subsequent checks examining
500 the output. Instead, save only the relevant git command's standard
501 error:
502
503 ( cd dir && git cmd 2>../error ) &&
504 test_cmp expect error
505
506 - Break the TAP output
507
508 The raw output from your test may be interpreted by a TAP harness. TAP
509 harnesses will ignore everything they don't know about, but don't step
510 on their toes in these areas:
511
512 - Don't print lines like "$x..$y" where $x and $y are integers.
513
514 - Don't print lines that begin with "ok" or "not ok".
515
516 TAP harnesses expect a line that begins with either "ok" and "not
517 ok" to signal a test passed or failed (and our harness already
518 produces such lines), so your script shouldn't emit such lines to
519 their output.
520
521 You can glean some further possible issues from the TAP grammar
522 (see https://metacpan.org/pod/TAP::Parser::Grammar#TAP-GRAMMAR)
523 but the best indication is to just run the tests with prove(1),
524 it'll complain if anything is amiss.
525
526 Keep in mind:
527
528 - Inside the <script> part, the standard output and standard error
529 streams are discarded, and the test harness only reports "ok" or
530 "not ok" to the end user running the tests. Under --verbose, they
531 are shown to help debugging the tests.
532
533
534 Skipping tests
535 --------------
536
537 If you need to skip tests you should do so by using the three-arg form
538 of the test_* functions (see the "Test harness library" section
539 below), e.g.:
540
541 test_expect_success PERL 'I need Perl' '
542 perl -e "hlagh() if unf_unf()"
543 '
544
545 The advantage of skipping tests like this is that platforms that don't
546 have the PERL and other optional dependencies get an indication of how
547 many tests they're missing.
548
549 If the test code is too hairy for that (i.e. does a lot of setup work
550 outside test assertions) you can also skip all remaining tests by
551 setting skip_all and immediately call test_done:
552
553 if ! test_have_prereq PERL
554 then
555 skip_all='skipping perl interface tests, perl not available'
556 test_done
557 fi
558
559 The string you give to skip_all will be used as an explanation for why
560 the test was skipped.
561
562 End with test_done
563 ------------------
564
565 Your script will be a sequence of tests, using helper functions
566 from the test harness library. At the end of the script, call
567 'test_done'.
568
569
570 Test harness library
571 --------------------
572
573 There are a handful helper functions defined in the test harness
574 library for your script to use.
575
576 - test_expect_success [<prereq>] <message> <script>
577
578 Usually takes two strings as parameters, and evaluates the
579 <script>. If it yields success, test is considered
580 successful. <message> should state what it is testing.
581
582 Example:
583
584 test_expect_success \
585 'git-write-tree should be able to write an empty tree.' \
586 'tree=$(git-write-tree)'
587
588 If you supply three parameters the first will be taken to be a
589 prerequisite; see the test_set_prereq and test_have_prereq
590 documentation below:
591
592 test_expect_success TTY 'git --paginate rev-list uses a pager' \
593 ' ... '
594
595 You can also supply a comma-separated list of prerequisites, in the
596 rare case where your test depends on more than one:
597
598 test_expect_success PERL,PYTHON 'yo dawg' \
599 ' test $(perl -E 'print eval "1 +" . qx[python -c "print 2"]') == "4" '
600
601 - test_expect_failure [<prereq>] <message> <script>
602
603 This is NOT the opposite of test_expect_success, but is used
604 to mark a test that demonstrates a known breakage. Unlike
605 the usual test_expect_success tests, which say "ok" on
606 success and "FAIL" on failure, this will say "FIXED" on
607 success and "still broken" on failure. Failures from these
608 tests won't cause -i (immediate) to stop.
609
610 Like test_expect_success this function can optionally use a three
611 argument invocation with a prerequisite as the first argument.
612
613 - test_debug <script>
614
615 This takes a single argument, <script>, and evaluates it only
616 when the test script is started with --debug command line
617 argument. This is primarily meant for use during the
618 development of a new test script.
619
620 - debug <git-command>
621
622 Run a git command inside a debugger. This is primarily meant for
623 use when debugging a failing test script.
624
625 - test_done
626
627 Your test script must have test_done at the end. Its purpose
628 is to summarize successes and failures in the test script and
629 exit with an appropriate error code.
630
631 - test_tick
632
633 Make commit and tag names consistent by setting the author and
634 committer times to defined state. Subsequent calls will
635 advance the times by a fixed amount.
636
637 - test_commit <message> [<filename> [<contents>]]
638
639 Creates a commit with the given message, committing the given
640 file with the given contents (default for both is to reuse the
641 message string), and adds a tag (again reusing the message
642 string as name). Calls test_tick to make the SHA-1s
643 reproducible.
644
645 - test_merge <message> <commit-or-tag>
646
647 Merges the given rev using the given message. Like test_commit,
648 creates a tag and calls test_tick before committing.
649
650 - test_set_prereq <prereq>
651
652 Set a test prerequisite to be used later with test_have_prereq. The
653 test-lib will set some prerequisites for you, see the
654 "Prerequisites" section below for a full list of these.
655
656 Others you can set yourself and use later with either
657 test_have_prereq directly, or the three argument invocation of
658 test_expect_success and test_expect_failure.
659
660 - test_have_prereq <prereq>
661
662 Check if we have a prerequisite previously set with test_set_prereq.
663 The most common way to use this explicitly (as opposed to the
664 implicit use when an argument is passed to test_expect_*) is to skip
665 all the tests at the start of the test script if we don't have some
666 essential prerequisite:
667
668 if ! test_have_prereq PERL
669 then
670 skip_all='skipping perl interface tests, perl not available'
671 test_done
672 fi
673
674 - test_external [<prereq>] <message> <external> <script>
675
676 Execute a <script> with an <external> interpreter (like perl). This
677 was added for tests like t9700-perl-git.sh which do most of their
678 work in an external test script.
679
680 test_external \
681 'GitwebCache::*FileCache*' \
682 perl "$TEST_DIRECTORY"/t9503/test_cache_interface.pl
683
684 If the test is outputting its own TAP you should set the
685 test_external_has_tap variable somewhere before calling the first
686 test_external* function. See t9700-perl-git.sh for an example.
687
688 # The external test will outputs its own plan
689 test_external_has_tap=1
690
691 - test_external_without_stderr [<prereq>] <message> <external> <script>
692
693 Like test_external but fail if there's any output on stderr,
694 instead of checking the exit code.
695
696 test_external_without_stderr \
697 'Perl API' \
698 perl "$TEST_DIRECTORY"/t9700/test.pl
699
700 - test_expect_code <exit-code> <command>
701
702 Run a command and ensure that it exits with the given exit code.
703 For example:
704
705 test_expect_success 'Merge with d/f conflicts' '
706 test_expect_code 1 git merge "merge msg" B master
707 '
708
709 - test_must_fail [<options>] <git-command>
710
711 Run a git command and ensure it fails in a controlled way. Use
712 this instead of "! <git-command>". When git-command dies due to a
713 segfault, test_must_fail diagnoses it as an error; "! <git-command>"
714 treats it as just another expected failure, which would let such a
715 bug go unnoticed.
716
717 Accepts the following options:
718
719 ok=<signal-name>[,<...>]:
720 Don't treat an exit caused by the given signal as error.
721 Multiple signals can be specified as a comma separated list.
722 Currently recognized signal names are: sigpipe, success.
723 (Don't use 'success', use 'test_might_fail' instead.)
724
725 - test_might_fail [<options>] <git-command>
726
727 Similar to test_must_fail, but tolerate success, too. Use this
728 instead of "<git-command> || :" to catch failures due to segv.
729
730 Accepts the same options as test_must_fail.
731
732 - test_cmp <expected> <actual>
733
734 Check whether the content of the <actual> file matches the
735 <expected> file. This behaves like "cmp" but produces more
736 helpful output when the test is run with "-v" option.
737
738 - test_cmp_rev <expected> <actual>
739
740 Check whether the <expected> rev points to the same commit as the
741 <actual> rev.
742
743 - test_line_count (= | -lt | -ge | ...) <length> <file>
744
745 Check whether a file has the length it is expected to.
746
747 - test_path_is_file <path> [<diagnosis>]
748 test_path_is_dir <path> [<diagnosis>]
749 test_path_is_missing <path> [<diagnosis>]
750
751 Check if the named path is a file, if the named path is a
752 directory, or if the named path does not exist, respectively,
753 and fail otherwise, showing the <diagnosis> text.
754
755 - test_when_finished <script>
756
757 Prepend <script> to a list of commands to run to clean up
758 at the end of the current test. If some clean-up command
759 fails, the test will not pass.
760
761 Example:
762
763 test_expect_success 'branch pointing to non-commit' '
764 git rev-parse HEAD^{tree} >.git/refs/heads/invalid &&
765 test_when_finished "git update-ref -d refs/heads/invalid" &&
766 ...
767 '
768
769 - test_write_lines <lines>
770
771 Write <lines> on standard output, one line per argument.
772 Useful to prepare multi-line files in a compact form.
773
774 Example:
775
776 test_write_lines a b c d e f g >foo
777
778 Is a more compact equivalent of:
779 cat >foo <<-EOF
780 a
781 b
782 c
783 d
784 e
785 f
786 g
787 EOF
788
789
790 - test_pause
791
792 This command is useful for writing and debugging tests and must be
793 removed before submitting. It halts the execution of the test and
794 spawns a shell in the trash directory. Exit the shell to continue
795 the test. Example:
796
797 test_expect_success 'test' '
798 git do-something >actual &&
799 test_pause &&
800 test_cmp expected actual
801 '
802
803 - test_ln_s_add <path1> <path2>
804
805 This function helps systems whose filesystem does not support symbolic
806 links. Use it to add a symbolic link entry to the index when it is not
807 important that the file system entry is a symbolic link, i.e., instead
808 of the sequence
809
810 ln -s foo bar &&
811 git add bar
812
813 Sometimes it is possible to split a test in a part that does not need
814 the symbolic link in the file system and a part that does; then only
815 the latter part need be protected by a SYMLINKS prerequisite (see below).
816
817 Prerequisites
818 -------------
819
820 These are the prerequisites that the test library predefines with
821 test_have_prereq.
822
823 See the prereq argument to the test_* functions in the "Test harness
824 library" section above and the "test_have_prereq" function for how to
825 use these, and "test_set_prereq" for how to define your own.
826
827 - PYTHON
828
829 Git wasn't compiled with NO_PYTHON=YesPlease. Wrap any tests that
830 need Python with this.
831
832 - PERL
833
834 Git wasn't compiled with NO_PERL=YesPlease.
835
836 Even without the PERL prerequisite, tests can assume there is a
837 usable perl interpreter at $PERL_PATH, though it need not be
838 particularly modern.
839
840 - POSIXPERM
841
842 The filesystem supports POSIX style permission bits.
843
844 - BSLASHPSPEC
845
846 Backslashes in pathspec are not directory separators. This is not
847 set on Windows. See 6fd1106a for details.
848
849 - EXECKEEPSPID
850
851 The process retains the same pid across exec(2). See fb9a2bea for
852 details.
853
854 - PIPE
855
856 The filesystem we're on supports creation of FIFOs (named pipes)
857 via mkfifo(1).
858
859 - SYMLINKS
860
861 The filesystem we're on supports symbolic links. E.g. a FAT
862 filesystem doesn't support these. See 704a3143 for details.
863
864 - SANITY
865
866 Test is not run by root user, and an attempt to write to an
867 unwritable file is expected to fail correctly.
868
869 - PCRE
870
871 Git was compiled with support for PCRE. Wrap any tests
872 that use git-grep --perl-regexp or git-grep -P in these.
873
874 - LIBPCRE1
875
876 Git was compiled with PCRE v1 support via
877 USE_LIBPCRE1=YesPlease. Wrap any PCRE using tests that for some
878 reason need v1 of the PCRE library instead of v2 in these.
879
880 - LIBPCRE2
881
882 Git was compiled with PCRE v2 support via
883 USE_LIBPCRE2=YesPlease. Wrap any PCRE using tests that for some
884 reason need v2 of the PCRE library instead of v1 in these.
885
886 - CASE_INSENSITIVE_FS
887
888 Test is run on a case insensitive file system.
889
890 - UTF8_NFD_TO_NFC
891
892 Test is run on a filesystem which converts decomposed utf-8 (nfd)
893 to precomposed utf-8 (nfc).
894
895 - PTHREADS
896
897 Git wasn't compiled with NO_PTHREADS=YesPlease.
898
899 Tips for Writing Tests
900 ----------------------
901
902 As with any programming projects, existing programs are the best
903 source of the information. However, do _not_ emulate
904 t0000-basic.sh when writing your tests. The test is special in
905 that it tries to validate the very core of GIT. For example, it
906 knows that there will be 256 subdirectories under .git/objects/,
907 and it knows that the object ID of an empty tree is a certain
908 40-byte string. This is deliberately done so in t0000-basic.sh
909 because the things the very basic core test tries to achieve is
910 to serve as a basis for people who are changing the GIT internal
911 drastically. For these people, after making certain changes,
912 not seeing failures from the basic test _is_ a failure. And
913 such drastic changes to the core GIT that even changes these
914 otherwise supposedly stable object IDs should be accompanied by
915 an update to t0000-basic.sh.
916
917 However, other tests that simply rely on basic parts of the core
918 GIT working properly should not have that level of intimate
919 knowledge of the core GIT internals. If all the test scripts
920 hardcoded the object IDs like t0000-basic.sh does, that defeats
921 the purpose of t0000-basic.sh, which is to isolate that level of
922 validation in one place. Your test also ends up needing
923 updating when such a change to the internal happens, so do _not_
924 do it and leave the low level of validation to t0000-basic.sh.
925
926 Test coverage
927 -------------
928
929 You can use the coverage tests to find code paths that are not being
930 used or properly exercised yet.
931
932 To do that, run the coverage target at the top-level (not in the t/
933 directory):
934
935 make coverage
936
937 That'll compile Git with GCC's coverage arguments, and generate a test
938 report with gcov after the tests finish. Running the coverage tests
939 can take a while, since running the tests in parallel is incompatible
940 with GCC's coverage mode.
941
942 After the tests have run you can generate a list of untested
943 functions:
944
945 make coverage-untested-functions
946
947 You can also generate a detailed per-file HTML report using the
948 Devel::Cover module. To install it do:
949
950 # On Debian or Ubuntu:
951 sudo aptitude install libdevel-cover-perl
952
953 # From the CPAN with cpanminus
954 curl -L http://cpanmin.us | perl - --sudo --self-upgrade
955 cpanm --sudo Devel::Cover
956
957 Then, at the top-level:
958
959 make cover_db_html
960
961 That'll generate a detailed cover report in the "cover_db_html"
962 directory, which you can then copy to a webserver, or inspect locally
963 in a browser.