commit-graph: define GIT_TEST_COMMIT_GRAPH
[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_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to
323 be written after every 'git commit' command, and overrides the
324 'core.commitGraph' setting to true.
325
326 Naming Tests
327 ------------
328
329 The test files are named as:
330
331 tNNNN-commandname-details.sh
332
333 where N is a decimal digit.
334
335 First digit tells the family:
336
337 0 - the absolute basics and global stuff
338 1 - the basic commands concerning database
339 2 - the basic commands concerning the working tree
340 3 - the other basic commands (e.g. ls-files)
341 4 - the diff commands
342 5 - the pull and exporting commands
343 6 - the revision tree commands (even e.g. merge-base)
344 7 - the porcelainish commands concerning the working tree
345 8 - the porcelainish commands concerning forensics
346 9 - the git tools
347
348 Second digit tells the particular command we are testing.
349
350 Third digit (optionally) tells the particular switch or group of switches
351 we are testing.
352
353 If you create files under t/ directory (i.e. here) that is not
354 the top-level test script, never name the file to match the above
355 pattern. The Makefile here considers all such files as the
356 top-level test script and tries to run all of them. Care is
357 especially needed if you are creating a common test library
358 file, similar to test-lib.sh, because such a library file may
359 not be suitable for standalone execution.
360
361
362 Writing Tests
363 -------------
364
365 The test script is written as a shell script. It should start
366 with the standard "#!/bin/sh", and an
367 assignment to variable 'test_description', like this:
368
369 #!/bin/sh
370
371 test_description='xxx test (option --frotz)
372
373 This test registers the following structure in the cache
374 and tries to run git-ls-files with option --frotz.'
375
376
377 Source 'test-lib.sh'
378 --------------------
379
380 After assigning test_description, the test script should source
381 test-lib.sh like this:
382
383 . ./test-lib.sh
384
385 This test harness library does the following things:
386
387 - If the script is invoked with command line argument --help
388 (or -h), it shows the test_description and exits.
389
390 - Creates an empty test directory with an empty .git/objects database
391 and chdir(2) into it. This directory is 't/trash
392 directory.$test_name_without_dotsh', with t/ subject to change by
393 the --root option documented above.
394
395 - Defines standard test helper functions for your scripts to
396 use. These functions are designed to make all scripts behave
397 consistently when command line arguments --verbose (or -v),
398 --debug (or -d), and --immediate (or -i) is given.
399
400 Do's, don'ts & things to keep in mind
401 -------------------------------------
402
403 Here are a few examples of things you probably should and shouldn't do
404 when writing tests.
405
406 Do:
407
408 - Put all code inside test_expect_success and other assertions.
409
410 Even code that isn't a test per se, but merely some setup code
411 should be inside a test assertion.
412
413 - Chain your test assertions
414
415 Write test code like this:
416
417 git merge foo &&
418 git push bar &&
419 test ...
420
421 Instead of:
422
423 git merge hla
424 git push gh
425 test ...
426
427 That way all of the commands in your tests will succeed or fail. If
428 you must ignore the return value of something, consider using a
429 helper function (e.g. use sane_unset instead of unset, in order
430 to avoid unportable return value for unsetting a variable that was
431 already unset), or prepending the command with test_might_fail or
432 test_must_fail.
433
434 - Check the test coverage for your tests. See the "Test coverage"
435 below.
436
437 Don't blindly follow test coverage metrics; if a new function you added
438 doesn't have any coverage, then you're probably doing something wrong,
439 but having 100% coverage doesn't necessarily mean that you tested
440 everything.
441
442 Tests that are likely to smoke out future regressions are better
443 than tests that just inflate the coverage metrics.
444
445 - When a test checks for an absolute path that a git command generated,
446 construct the expected value using $(pwd) rather than $PWD,
447 $TEST_DIRECTORY, or $TRASH_DIRECTORY. It makes a difference on
448 Windows, where the shell (MSYS bash) mangles absolute path names.
449 For details, see the commit message of 4114156ae9.
450
451 Don't:
452
453 - exit() within a <script> part.
454
455 The harness will catch this as a programming error of the test.
456 Use test_done instead if you need to stop the tests early (see
457 "Skipping tests" below).
458
459 - use '! git cmd' when you want to make sure the git command exits
460 with failure in a controlled way by calling "die()". Instead,
461 use 'test_must_fail git cmd'. This will signal a failure if git
462 dies in an unexpected way (e.g. segfault).
463
464 On the other hand, don't use test_must_fail for running regular
465 platform commands; just use '! cmd'. We are not in the business
466 of verifying that the world given to us sanely works.
467
468 - use perl without spelling it as "$PERL_PATH". This is to help our
469 friends on Windows where the platform Perl often adds CR before
470 the end of line, and they bundle Git with a version of Perl that
471 does not do so, whose path is specified with $PERL_PATH. Note that we
472 provide a "perl" function which uses $PERL_PATH under the hood, so
473 you do not need to worry when simply running perl in the test scripts
474 (but you do, for example, on a shebang line or in a sub script
475 created via "write_script").
476
477 - use sh without spelling it as "$SHELL_PATH", when the script can
478 be misinterpreted by broken platform shell (e.g. Solaris).
479
480 - chdir around in tests. It is not sufficient to chdir to
481 somewhere and then chdir back to the original location later in
482 the test, as any intermediate step can fail and abort the test,
483 causing the next test to start in an unexpected directory. Do so
484 inside a subshell if necessary.
485
486 - save and verify the standard error of compound commands, i.e. group
487 commands, subshells, and shell functions (except test helper
488 functions like 'test_must_fail') like this:
489
490 ( cd dir && git cmd ) 2>error &&
491 test_cmp expect error
492
493 When running the test with '-x' tracing, then the trace of commands
494 executed in the compound command will be included in standard error
495 as well, quite possibly throwing off the subsequent checks examining
496 the output. Instead, save only the relevant git command's standard
497 error:
498
499 ( cd dir && git cmd 2>../error ) &&
500 test_cmp expect error
501
502 - Break the TAP output
503
504 The raw output from your test may be interpreted by a TAP harness. TAP
505 harnesses will ignore everything they don't know about, but don't step
506 on their toes in these areas:
507
508 - Don't print lines like "$x..$y" where $x and $y are integers.
509
510 - Don't print lines that begin with "ok" or "not ok".
511
512 TAP harnesses expect a line that begins with either "ok" and "not
513 ok" to signal a test passed or failed (and our harness already
514 produces such lines), so your script shouldn't emit such lines to
515 their output.
516
517 You can glean some further possible issues from the TAP grammar
518 (see https://metacpan.org/pod/TAP::Parser::Grammar#TAP-GRAMMAR)
519 but the best indication is to just run the tests with prove(1),
520 it'll complain if anything is amiss.
521
522 Keep in mind:
523
524 - Inside the <script> part, the standard output and standard error
525 streams are discarded, and the test harness only reports "ok" or
526 "not ok" to the end user running the tests. Under --verbose, they
527 are shown to help debugging the tests.
528
529
530 Skipping tests
531 --------------
532
533 If you need to skip tests you should do so by using the three-arg form
534 of the test_* functions (see the "Test harness library" section
535 below), e.g.:
536
537 test_expect_success PERL 'I need Perl' '
538 perl -e "hlagh() if unf_unf()"
539 '
540
541 The advantage of skipping tests like this is that platforms that don't
542 have the PERL and other optional dependencies get an indication of how
543 many tests they're missing.
544
545 If the test code is too hairy for that (i.e. does a lot of setup work
546 outside test assertions) you can also skip all remaining tests by
547 setting skip_all and immediately call test_done:
548
549 if ! test_have_prereq PERL
550 then
551 skip_all='skipping perl interface tests, perl not available'
552 test_done
553 fi
554
555 The string you give to skip_all will be used as an explanation for why
556 the test was skipped.
557
558 End with test_done
559 ------------------
560
561 Your script will be a sequence of tests, using helper functions
562 from the test harness library. At the end of the script, call
563 'test_done'.
564
565
566 Test harness library
567 --------------------
568
569 There are a handful helper functions defined in the test harness
570 library for your script to use.
571
572 - test_expect_success [<prereq>] <message> <script>
573
574 Usually takes two strings as parameters, and evaluates the
575 <script>. If it yields success, test is considered
576 successful. <message> should state what it is testing.
577
578 Example:
579
580 test_expect_success \
581 'git-write-tree should be able to write an empty tree.' \
582 'tree=$(git-write-tree)'
583
584 If you supply three parameters the first will be taken to be a
585 prerequisite; see the test_set_prereq and test_have_prereq
586 documentation below:
587
588 test_expect_success TTY 'git --paginate rev-list uses a pager' \
589 ' ... '
590
591 You can also supply a comma-separated list of prerequisites, in the
592 rare case where your test depends on more than one:
593
594 test_expect_success PERL,PYTHON 'yo dawg' \
595 ' test $(perl -E 'print eval "1 +" . qx[python -c "print 2"]') == "4" '
596
597 - test_expect_failure [<prereq>] <message> <script>
598
599 This is NOT the opposite of test_expect_success, but is used
600 to mark a test that demonstrates a known breakage. Unlike
601 the usual test_expect_success tests, which say "ok" on
602 success and "FAIL" on failure, this will say "FIXED" on
603 success and "still broken" on failure. Failures from these
604 tests won't cause -i (immediate) to stop.
605
606 Like test_expect_success this function can optionally use a three
607 argument invocation with a prerequisite as the first argument.
608
609 - test_debug <script>
610
611 This takes a single argument, <script>, and evaluates it only
612 when the test script is started with --debug command line
613 argument. This is primarily meant for use during the
614 development of a new test script.
615
616 - debug <git-command>
617
618 Run a git command inside a debugger. This is primarily meant for
619 use when debugging a failing test script.
620
621 - test_done
622
623 Your test script must have test_done at the end. Its purpose
624 is to summarize successes and failures in the test script and
625 exit with an appropriate error code.
626
627 - test_tick
628
629 Make commit and tag names consistent by setting the author and
630 committer times to defined state. Subsequent calls will
631 advance the times by a fixed amount.
632
633 - test_commit <message> [<filename> [<contents>]]
634
635 Creates a commit with the given message, committing the given
636 file with the given contents (default for both is to reuse the
637 message string), and adds a tag (again reusing the message
638 string as name). Calls test_tick to make the SHA-1s
639 reproducible.
640
641 - test_merge <message> <commit-or-tag>
642
643 Merges the given rev using the given message. Like test_commit,
644 creates a tag and calls test_tick before committing.
645
646 - test_set_prereq <prereq>
647
648 Set a test prerequisite to be used later with test_have_prereq. The
649 test-lib will set some prerequisites for you, see the
650 "Prerequisites" section below for a full list of these.
651
652 Others you can set yourself and use later with either
653 test_have_prereq directly, or the three argument invocation of
654 test_expect_success and test_expect_failure.
655
656 - test_have_prereq <prereq>
657
658 Check if we have a prerequisite previously set with test_set_prereq.
659 The most common way to use this explicitly (as opposed to the
660 implicit use when an argument is passed to test_expect_*) is to skip
661 all the tests at the start of the test script if we don't have some
662 essential prerequisite:
663
664 if ! test_have_prereq PERL
665 then
666 skip_all='skipping perl interface tests, perl not available'
667 test_done
668 fi
669
670 - test_external [<prereq>] <message> <external> <script>
671
672 Execute a <script> with an <external> interpreter (like perl). This
673 was added for tests like t9700-perl-git.sh which do most of their
674 work in an external test script.
675
676 test_external \
677 'GitwebCache::*FileCache*' \
678 perl "$TEST_DIRECTORY"/t9503/test_cache_interface.pl
679
680 If the test is outputting its own TAP you should set the
681 test_external_has_tap variable somewhere before calling the first
682 test_external* function. See t9700-perl-git.sh for an example.
683
684 # The external test will outputs its own plan
685 test_external_has_tap=1
686
687 - test_external_without_stderr [<prereq>] <message> <external> <script>
688
689 Like test_external but fail if there's any output on stderr,
690 instead of checking the exit code.
691
692 test_external_without_stderr \
693 'Perl API' \
694 perl "$TEST_DIRECTORY"/t9700/test.pl
695
696 - test_expect_code <exit-code> <command>
697
698 Run a command and ensure that it exits with the given exit code.
699 For example:
700
701 test_expect_success 'Merge with d/f conflicts' '
702 test_expect_code 1 git merge "merge msg" B master
703 '
704
705 - test_must_fail [<options>] <git-command>
706
707 Run a git command and ensure it fails in a controlled way. Use
708 this instead of "! <git-command>". When git-command dies due to a
709 segfault, test_must_fail diagnoses it as an error; "! <git-command>"
710 treats it as just another expected failure, which would let such a
711 bug go unnoticed.
712
713 Accepts the following options:
714
715 ok=<signal-name>[,<...>]:
716 Don't treat an exit caused by the given signal as error.
717 Multiple signals can be specified as a comma separated list.
718 Currently recognized signal names are: sigpipe, success.
719 (Don't use 'success', use 'test_might_fail' instead.)
720
721 - test_might_fail [<options>] <git-command>
722
723 Similar to test_must_fail, but tolerate success, too. Use this
724 instead of "<git-command> || :" to catch failures due to segv.
725
726 Accepts the same options as test_must_fail.
727
728 - test_cmp <expected> <actual>
729
730 Check whether the content of the <actual> file matches the
731 <expected> file. This behaves like "cmp" but produces more
732 helpful output when the test is run with "-v" option.
733
734 - test_cmp_rev <expected> <actual>
735
736 Check whether the <expected> rev points to the same commit as the
737 <actual> rev.
738
739 - test_line_count (= | -lt | -ge | ...) <length> <file>
740
741 Check whether a file has the length it is expected to.
742
743 - test_path_is_file <path> [<diagnosis>]
744 test_path_is_dir <path> [<diagnosis>]
745 test_path_is_missing <path> [<diagnosis>]
746
747 Check if the named path is a file, if the named path is a
748 directory, or if the named path does not exist, respectively,
749 and fail otherwise, showing the <diagnosis> text.
750
751 - test_when_finished <script>
752
753 Prepend <script> to a list of commands to run to clean up
754 at the end of the current test. If some clean-up command
755 fails, the test will not pass.
756
757 Example:
758
759 test_expect_success 'branch pointing to non-commit' '
760 git rev-parse HEAD^{tree} >.git/refs/heads/invalid &&
761 test_when_finished "git update-ref -d refs/heads/invalid" &&
762 ...
763 '
764
765 - test_write_lines <lines>
766
767 Write <lines> on standard output, one line per argument.
768 Useful to prepare multi-line files in a compact form.
769
770 Example:
771
772 test_write_lines a b c d e f g >foo
773
774 Is a more compact equivalent of:
775 cat >foo <<-EOF
776 a
777 b
778 c
779 d
780 e
781 f
782 g
783 EOF
784
785
786 - test_pause
787
788 This command is useful for writing and debugging tests and must be
789 removed before submitting. It halts the execution of the test and
790 spawns a shell in the trash directory. Exit the shell to continue
791 the test. Example:
792
793 test_expect_success 'test' '
794 git do-something >actual &&
795 test_pause &&
796 test_cmp expected actual
797 '
798
799 - test_ln_s_add <path1> <path2>
800
801 This function helps systems whose filesystem does not support symbolic
802 links. Use it to add a symbolic link entry to the index when it is not
803 important that the file system entry is a symbolic link, i.e., instead
804 of the sequence
805
806 ln -s foo bar &&
807 git add bar
808
809 Sometimes it is possible to split a test in a part that does not need
810 the symbolic link in the file system and a part that does; then only
811 the latter part need be protected by a SYMLINKS prerequisite (see below).
812
813 Prerequisites
814 -------------
815
816 These are the prerequisites that the test library predefines with
817 test_have_prereq.
818
819 See the prereq argument to the test_* functions in the "Test harness
820 library" section above and the "test_have_prereq" function for how to
821 use these, and "test_set_prereq" for how to define your own.
822
823 - PYTHON
824
825 Git wasn't compiled with NO_PYTHON=YesPlease. Wrap any tests that
826 need Python with this.
827
828 - PERL
829
830 Git wasn't compiled with NO_PERL=YesPlease.
831
832 Even without the PERL prerequisite, tests can assume there is a
833 usable perl interpreter at $PERL_PATH, though it need not be
834 particularly modern.
835
836 - POSIXPERM
837
838 The filesystem supports POSIX style permission bits.
839
840 - BSLASHPSPEC
841
842 Backslashes in pathspec are not directory separators. This is not
843 set on Windows. See 6fd1106a for details.
844
845 - EXECKEEPSPID
846
847 The process retains the same pid across exec(2). See fb9a2bea for
848 details.
849
850 - PIPE
851
852 The filesystem we're on supports creation of FIFOs (named pipes)
853 via mkfifo(1).
854
855 - SYMLINKS
856
857 The filesystem we're on supports symbolic links. E.g. a FAT
858 filesystem doesn't support these. See 704a3143 for details.
859
860 - SANITY
861
862 Test is not run by root user, and an attempt to write to an
863 unwritable file is expected to fail correctly.
864
865 - PCRE
866
867 Git was compiled with support for PCRE. Wrap any tests
868 that use git-grep --perl-regexp or git-grep -P in these.
869
870 - LIBPCRE1
871
872 Git was compiled with PCRE v1 support via
873 USE_LIBPCRE1=YesPlease. Wrap any PCRE using tests that for some
874 reason need v1 of the PCRE library instead of v2 in these.
875
876 - LIBPCRE2
877
878 Git was compiled with PCRE v2 support via
879 USE_LIBPCRE2=YesPlease. Wrap any PCRE using tests that for some
880 reason need v2 of the PCRE library instead of v1 in these.
881
882 - CASE_INSENSITIVE_FS
883
884 Test is run on a case insensitive file system.
885
886 - UTF8_NFD_TO_NFC
887
888 Test is run on a filesystem which converts decomposed utf-8 (nfd)
889 to precomposed utf-8 (nfc).
890
891 - PTHREADS
892
893 Git wasn't compiled with NO_PTHREADS=YesPlease.
894
895 Tips for Writing Tests
896 ----------------------
897
898 As with any programming projects, existing programs are the best
899 source of the information. However, do _not_ emulate
900 t0000-basic.sh when writing your tests. The test is special in
901 that it tries to validate the very core of GIT. For example, it
902 knows that there will be 256 subdirectories under .git/objects/,
903 and it knows that the object ID of an empty tree is a certain
904 40-byte string. This is deliberately done so in t0000-basic.sh
905 because the things the very basic core test tries to achieve is
906 to serve as a basis for people who are changing the GIT internal
907 drastically. For these people, after making certain changes,
908 not seeing failures from the basic test _is_ a failure. And
909 such drastic changes to the core GIT that even changes these
910 otherwise supposedly stable object IDs should be accompanied by
911 an update to t0000-basic.sh.
912
913 However, other tests that simply rely on basic parts of the core
914 GIT working properly should not have that level of intimate
915 knowledge of the core GIT internals. If all the test scripts
916 hardcoded the object IDs like t0000-basic.sh does, that defeats
917 the purpose of t0000-basic.sh, which is to isolate that level of
918 validation in one place. Your test also ends up needing
919 updating when such a change to the internal happens, so do _not_
920 do it and leave the low level of validation to t0000-basic.sh.
921
922 Test coverage
923 -------------
924
925 You can use the coverage tests to find code paths that are not being
926 used or properly exercised yet.
927
928 To do that, run the coverage target at the top-level (not in the t/
929 directory):
930
931 make coverage
932
933 That'll compile Git with GCC's coverage arguments, and generate a test
934 report with gcov after the tests finish. Running the coverage tests
935 can take a while, since running the tests in parallel is incompatible
936 with GCC's coverage mode.
937
938 After the tests have run you can generate a list of untested
939 functions:
940
941 make coverage-untested-functions
942
943 You can also generate a detailed per-file HTML report using the
944 Devel::Cover module. To install it do:
945
946 # On Debian or Ubuntu:
947 sudo aptitude install libdevel-cover-perl
948
949 # From the CPAN with cpanminus
950 curl -L http://cpanmin.us | perl - --sudo --self-upgrade
951 cpanm --sudo Devel::Cover
952
953 Then, at the top-level:
954
955 make cover_db_html
956
957 That'll generate a detailed cover report in the "cover_db_html"
958 directory, which you can then copy to a webserver, or inspect locally
959 in a browser.