i18n: make GETTEXT_POISON a runtime option
[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_GETTEXT_POISON=<non-empty?> turns all strings marked for
305 translation into gibberish if non-empty (think "test -n"). Used for
306 spotting those tests that need to be marked with a C_LOCALE_OUTPUT
307 prerequisite when adding more strings for translation. See "Testing
308 marked strings" in po/README for details.
309
310 GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole
311 test suite. Accept any boolean values that are accepted by git-config.
312
313 GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon
314 pack-objects code path where there are more than 1024 packs even if
315 the actual number of packs in repository is below this limit. Accept
316 any boolean values that are accepted by git-config.
317
318 GIT_TEST_OE_SIZE=<n> exercises the uncommon pack-objects code path
319 where we do not cache object size in memory and read it from existing
320 packs on demand. This normally only happens when the object size is
321 over 2GB. This variable forces the code path on any object larger than
322 <n> bytes.
323
324 GIT_TEST_OE_DELTA_SIZE=<n> exercises the uncommon pack-objects code
325 path where deltas larger than this limit require extra memory
326 allocation for bookkeeping.
327
328 GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES=<boolean> checks that cache-tree
329 records are valid when the index is written out or after a merge. This
330 is mostly to catch missing invalidation. Default is true.
331
332 GIT_TEST_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to
333 be written after every 'git commit' command, and overrides the
334 'core.commitGraph' setting to true.
335
336 GIT_TEST_FSMONITOR=$PWD/t7519/fsmonitor-all exercises the fsmonitor
337 code path for utilizing a file system monitor to speed up detecting
338 new or changed files.
339
340 GIT_TEST_INDEX_VERSION=<n> exercises the index read/write code path
341 for the index version specified. Can be set to any valid version
342 (currently 2, 3, or 4).
343
344 GIT_TEST_PRELOAD_INDEX=<boolean> exercises the preload-index code path
345 by overriding the minimum number of cache entries required per thread.
346
347 GIT_TEST_INDEX_THREADS=<n> enables exercising the multi-threaded loading
348 of the index for the whole test suite by bypassing the default number of
349 cache entries and thread minimums. Setting this to 1 will make the
350 index loading single threaded.
351
352 Naming Tests
353 ------------
354
355 The test files are named as:
356
357 tNNNN-commandname-details.sh
358
359 where N is a decimal digit.
360
361 First digit tells the family:
362
363 0 - the absolute basics and global stuff
364 1 - the basic commands concerning database
365 2 - the basic commands concerning the working tree
366 3 - the other basic commands (e.g. ls-files)
367 4 - the diff commands
368 5 - the pull and exporting commands
369 6 - the revision tree commands (even e.g. merge-base)
370 7 - the porcelainish commands concerning the working tree
371 8 - the porcelainish commands concerning forensics
372 9 - the git tools
373
374 Second digit tells the particular command we are testing.
375
376 Third digit (optionally) tells the particular switch or group of switches
377 we are testing.
378
379 If you create files under t/ directory (i.e. here) that is not
380 the top-level test script, never name the file to match the above
381 pattern. The Makefile here considers all such files as the
382 top-level test script and tries to run all of them. Care is
383 especially needed if you are creating a common test library
384 file, similar to test-lib.sh, because such a library file may
385 not be suitable for standalone execution.
386
387
388 Writing Tests
389 -------------
390
391 The test script is written as a shell script. It should start
392 with the standard "#!/bin/sh", and an
393 assignment to variable 'test_description', like this:
394
395 #!/bin/sh
396
397 test_description='xxx test (option --frotz)
398
399 This test registers the following structure in the cache
400 and tries to run git-ls-files with option --frotz.'
401
402
403 Source 'test-lib.sh'
404 --------------------
405
406 After assigning test_description, the test script should source
407 test-lib.sh like this:
408
409 . ./test-lib.sh
410
411 This test harness library does the following things:
412
413 - If the script is invoked with command line argument --help
414 (or -h), it shows the test_description and exits.
415
416 - Creates an empty test directory with an empty .git/objects database
417 and chdir(2) into it. This directory is 't/trash
418 directory.$test_name_without_dotsh', with t/ subject to change by
419 the --root option documented above.
420
421 - Defines standard test helper functions for your scripts to
422 use. These functions are designed to make all scripts behave
423 consistently when command line arguments --verbose (or -v),
424 --debug (or -d), and --immediate (or -i) is given.
425
426 Do's & don'ts
427 -------------
428
429 Here are a few examples of things you probably should and shouldn't do
430 when writing tests.
431
432 Here are the "do's:"
433
434 - Put all code inside test_expect_success and other assertions.
435
436 Even code that isn't a test per se, but merely some setup code
437 should be inside a test assertion.
438
439 - Chain your test assertions
440
441 Write test code like this:
442
443 git merge foo &&
444 git push bar &&
445 test ...
446
447 Instead of:
448
449 git merge hla
450 git push gh
451 test ...
452
453 That way all of the commands in your tests will succeed or fail. If
454 you must ignore the return value of something, consider using a
455 helper function (e.g. use sane_unset instead of unset, in order
456 to avoid unportable return value for unsetting a variable that was
457 already unset), or prepending the command with test_might_fail or
458 test_must_fail.
459
460 - Check the test coverage for your tests. See the "Test coverage"
461 below.
462
463 Don't blindly follow test coverage metrics; if a new function you added
464 doesn't have any coverage, then you're probably doing something wrong,
465 but having 100% coverage doesn't necessarily mean that you tested
466 everything.
467
468 Tests that are likely to smoke out future regressions are better
469 than tests that just inflate the coverage metrics.
470
471 - When a test checks for an absolute path that a git command generated,
472 construct the expected value using $(pwd) rather than $PWD,
473 $TEST_DIRECTORY, or $TRASH_DIRECTORY. It makes a difference on
474 Windows, where the shell (MSYS bash) mangles absolute path names.
475 For details, see the commit message of 4114156ae9.
476
477 - Remember that inside the <script> part, the standard output and
478 standard error streams are discarded, and the test harness only
479 reports "ok" or "not ok" to the end user running the tests. Under
480 --verbose, they are shown to help debug the tests.
481
482 And here are the "don'ts:"
483
484 - Don't exit() within a <script> part.
485
486 The harness will catch this as a programming error of the test.
487 Use test_done instead if you need to stop the tests early (see
488 "Skipping tests" below).
489
490 - Don't use '! git cmd' when you want to make sure the git command
491 exits with failure in a controlled way by calling "die()". Instead,
492 use 'test_must_fail git cmd'. This will signal a failure if git
493 dies in an unexpected way (e.g. segfault).
494
495 On the other hand, don't use test_must_fail for running regular
496 platform commands; just use '! cmd'. We are not in the business
497 of verifying that the world given to us sanely works.
498
499 - Don't feed the output of a git command to a pipe, as in:
500
501 git -C repo ls-files |
502 xargs -n 1 basename |
503 grep foo
504
505 which will discard git's exit code and may mask a crash. In the
506 above example, all exit codes are ignored except grep's.
507
508 Instead, write the output of that command to a temporary
509 file with ">" or assign it to a variable with "x=$(git ...)" rather
510 than pipe it.
511
512 - Don't use command substitution in a way that discards git's exit
513 code. When assigning to a variable, the exit code is not discarded,
514 e.g.:
515
516 x=$(git cat-file -p $sha) &&
517 ...
518
519 is OK because a crash in "git cat-file" will cause the "&&" chain
520 to fail, but:
521
522 test "refs/heads/foo" = "$(git symbolic-ref HEAD)"
523
524 is not OK and a crash in git could go undetected.
525
526 - Don't use perl without spelling it as "$PERL_PATH". This is to help
527 our friends on Windows where the platform Perl often adds CR before
528 the end of line, and they bundle Git with a version of Perl that
529 does not do so, whose path is specified with $PERL_PATH. Note that we
530 provide a "perl" function which uses $PERL_PATH under the hood, so
531 you do not need to worry when simply running perl in the test scripts
532 (but you do, for example, on a shebang line or in a sub script
533 created via "write_script").
534
535 - Don't use sh without spelling it as "$SHELL_PATH", when the script
536 can be misinterpreted by broken platform shell (e.g. Solaris).
537
538 - Don't chdir around in tests. It is not sufficient to chdir to
539 somewhere and then chdir back to the original location later in
540 the test, as any intermediate step can fail and abort the test,
541 causing the next test to start in an unexpected directory. Do so
542 inside a subshell if necessary.
543
544 - Don't save and verify the standard error of compound commands, i.e.
545 group commands, subshells, and shell functions (except test helper
546 functions like 'test_must_fail') like this:
547
548 ( cd dir && git cmd ) 2>error &&
549 test_cmp expect error
550
551 When running the test with '-x' tracing, then the trace of commands
552 executed in the compound command will be included in standard error
553 as well, quite possibly throwing off the subsequent checks examining
554 the output. Instead, save only the relevant git command's standard
555 error:
556
557 ( cd dir && git cmd 2>../error ) &&
558 test_cmp expect error
559
560 - Don't break the TAP output
561
562 The raw output from your test may be interpreted by a TAP harness. TAP
563 harnesses will ignore everything they don't know about, but don't step
564 on their toes in these areas:
565
566 - Don't print lines like "$x..$y" where $x and $y are integers.
567
568 - Don't print lines that begin with "ok" or "not ok".
569
570 TAP harnesses expect a line that begins with either "ok" and "not
571 ok" to signal a test passed or failed (and our harness already
572 produces such lines), so your script shouldn't emit such lines to
573 their output.
574
575 You can glean some further possible issues from the TAP grammar
576 (see https://metacpan.org/pod/TAP::Parser::Grammar#TAP-GRAMMAR)
577 but the best indication is to just run the tests with prove(1),
578 it'll complain if anything is amiss.
579
580
581 Skipping tests
582 --------------
583
584 If you need to skip tests you should do so by using the three-arg form
585 of the test_* functions (see the "Test harness library" section
586 below), e.g.:
587
588 test_expect_success PERL 'I need Perl' '
589 perl -e "hlagh() if unf_unf()"
590 '
591
592 The advantage of skipping tests like this is that platforms that don't
593 have the PERL and other optional dependencies get an indication of how
594 many tests they're missing.
595
596 If the test code is too hairy for that (i.e. does a lot of setup work
597 outside test assertions) you can also skip all remaining tests by
598 setting skip_all and immediately call test_done:
599
600 if ! test_have_prereq PERL
601 then
602 skip_all='skipping perl interface tests, perl not available'
603 test_done
604 fi
605
606 The string you give to skip_all will be used as an explanation for why
607 the test was skipped.
608
609 End with test_done
610 ------------------
611
612 Your script will be a sequence of tests, using helper functions
613 from the test harness library. At the end of the script, call
614 'test_done'.
615
616
617 Test harness library
618 --------------------
619
620 There are a handful helper functions defined in the test harness
621 library for your script to use.
622
623 - test_expect_success [<prereq>] <message> <script>
624
625 Usually takes two strings as parameters, and evaluates the
626 <script>. If it yields success, test is considered
627 successful. <message> should state what it is testing.
628
629 Example:
630
631 test_expect_success \
632 'git-write-tree should be able to write an empty tree.' \
633 'tree=$(git-write-tree)'
634
635 If you supply three parameters the first will be taken to be a
636 prerequisite; see the test_set_prereq and test_have_prereq
637 documentation below:
638
639 test_expect_success TTY 'git --paginate rev-list uses a pager' \
640 ' ... '
641
642 You can also supply a comma-separated list of prerequisites, in the
643 rare case where your test depends on more than one:
644
645 test_expect_success PERL,PYTHON 'yo dawg' \
646 ' test $(perl -E 'print eval "1 +" . qx[python -c "print 2"]') == "4" '
647
648 - test_expect_failure [<prereq>] <message> <script>
649
650 This is NOT the opposite of test_expect_success, but is used
651 to mark a test that demonstrates a known breakage. Unlike
652 the usual test_expect_success tests, which say "ok" on
653 success and "FAIL" on failure, this will say "FIXED" on
654 success and "still broken" on failure. Failures from these
655 tests won't cause -i (immediate) to stop.
656
657 Like test_expect_success this function can optionally use a three
658 argument invocation with a prerequisite as the first argument.
659
660 - test_debug <script>
661
662 This takes a single argument, <script>, and evaluates it only
663 when the test script is started with --debug command line
664 argument. This is primarily meant for use during the
665 development of a new test script.
666
667 - debug <git-command>
668
669 Run a git command inside a debugger. This is primarily meant for
670 use when debugging a failing test script.
671
672 - test_done
673
674 Your test script must have test_done at the end. Its purpose
675 is to summarize successes and failures in the test script and
676 exit with an appropriate error code.
677
678 - test_tick
679
680 Make commit and tag names consistent by setting the author and
681 committer times to defined state. Subsequent calls will
682 advance the times by a fixed amount.
683
684 - test_commit <message> [<filename> [<contents>]]
685
686 Creates a commit with the given message, committing the given
687 file with the given contents (default for both is to reuse the
688 message string), and adds a tag (again reusing the message
689 string as name). Calls test_tick to make the SHA-1s
690 reproducible.
691
692 - test_merge <message> <commit-or-tag>
693
694 Merges the given rev using the given message. Like test_commit,
695 creates a tag and calls test_tick before committing.
696
697 - test_set_prereq <prereq>
698
699 Set a test prerequisite to be used later with test_have_prereq. The
700 test-lib will set some prerequisites for you, see the
701 "Prerequisites" section below for a full list of these.
702
703 Others you can set yourself and use later with either
704 test_have_prereq directly, or the three argument invocation of
705 test_expect_success and test_expect_failure.
706
707 - test_have_prereq <prereq>
708
709 Check if we have a prerequisite previously set with test_set_prereq.
710 The most common way to use this explicitly (as opposed to the
711 implicit use when an argument is passed to test_expect_*) is to skip
712 all the tests at the start of the test script if we don't have some
713 essential prerequisite:
714
715 if ! test_have_prereq PERL
716 then
717 skip_all='skipping perl interface tests, perl not available'
718 test_done
719 fi
720
721 - test_external [<prereq>] <message> <external> <script>
722
723 Execute a <script> with an <external> interpreter (like perl). This
724 was added for tests like t9700-perl-git.sh which do most of their
725 work in an external test script.
726
727 test_external \
728 'GitwebCache::*FileCache*' \
729 perl "$TEST_DIRECTORY"/t9503/test_cache_interface.pl
730
731 If the test is outputting its own TAP you should set the
732 test_external_has_tap variable somewhere before calling the first
733 test_external* function. See t9700-perl-git.sh for an example.
734
735 # The external test will outputs its own plan
736 test_external_has_tap=1
737
738 - test_external_without_stderr [<prereq>] <message> <external> <script>
739
740 Like test_external but fail if there's any output on stderr,
741 instead of checking the exit code.
742
743 test_external_without_stderr \
744 'Perl API' \
745 perl "$TEST_DIRECTORY"/t9700/test.pl
746
747 - test_expect_code <exit-code> <command>
748
749 Run a command and ensure that it exits with the given exit code.
750 For example:
751
752 test_expect_success 'Merge with d/f conflicts' '
753 test_expect_code 1 git merge "merge msg" B master
754 '
755
756 - test_must_fail [<options>] <git-command>
757
758 Run a git command and ensure it fails in a controlled way. Use
759 this instead of "! <git-command>". When git-command dies due to a
760 segfault, test_must_fail diagnoses it as an error; "! <git-command>"
761 treats it as just another expected failure, which would let such a
762 bug go unnoticed.
763
764 Accepts the following options:
765
766 ok=<signal-name>[,<...>]:
767 Don't treat an exit caused by the given signal as error.
768 Multiple signals can be specified as a comma separated list.
769 Currently recognized signal names are: sigpipe, success.
770 (Don't use 'success', use 'test_might_fail' instead.)
771
772 - test_might_fail [<options>] <git-command>
773
774 Similar to test_must_fail, but tolerate success, too. Use this
775 instead of "<git-command> || :" to catch failures due to segv.
776
777 Accepts the same options as test_must_fail.
778
779 - test_cmp <expected> <actual>
780
781 Check whether the content of the <actual> file matches the
782 <expected> file. This behaves like "cmp" but produces more
783 helpful output when the test is run with "-v" option.
784
785 - test_cmp_rev <expected> <actual>
786
787 Check whether the <expected> rev points to the same commit as the
788 <actual> rev.
789
790 - test_line_count (= | -lt | -ge | ...) <length> <file>
791
792 Check whether a file has the length it is expected to.
793
794 - test_path_is_file <path> [<diagnosis>]
795 test_path_is_dir <path> [<diagnosis>]
796 test_path_is_missing <path> [<diagnosis>]
797
798 Check if the named path is a file, if the named path is a
799 directory, or if the named path does not exist, respectively,
800 and fail otherwise, showing the <diagnosis> text.
801
802 - test_when_finished <script>
803
804 Prepend <script> to a list of commands to run to clean up
805 at the end of the current test. If some clean-up command
806 fails, the test will not pass.
807
808 Example:
809
810 test_expect_success 'branch pointing to non-commit' '
811 git rev-parse HEAD^{tree} >.git/refs/heads/invalid &&
812 test_when_finished "git update-ref -d refs/heads/invalid" &&
813 ...
814 '
815
816 - test_write_lines <lines>
817
818 Write <lines> on standard output, one line per argument.
819 Useful to prepare multi-line files in a compact form.
820
821 Example:
822
823 test_write_lines a b c d e f g >foo
824
825 Is a more compact equivalent of:
826 cat >foo <<-EOF
827 a
828 b
829 c
830 d
831 e
832 f
833 g
834 EOF
835
836
837 - test_pause
838
839 This command is useful for writing and debugging tests and must be
840 removed before submitting. It halts the execution of the test and
841 spawns a shell in the trash directory. Exit the shell to continue
842 the test. Example:
843
844 test_expect_success 'test' '
845 git do-something >actual &&
846 test_pause &&
847 test_cmp expected actual
848 '
849
850 - test_ln_s_add <path1> <path2>
851
852 This function helps systems whose filesystem does not support symbolic
853 links. Use it to add a symbolic link entry to the index when it is not
854 important that the file system entry is a symbolic link, i.e., instead
855 of the sequence
856
857 ln -s foo bar &&
858 git add bar
859
860 Sometimes it is possible to split a test in a part that does not need
861 the symbolic link in the file system and a part that does; then only
862 the latter part need be protected by a SYMLINKS prerequisite (see below).
863
864 - test_oid_init
865
866 This function loads facts and useful object IDs related to the hash
867 algorithm(s) in use from the files in t/oid-info.
868
869 - test_oid_cache
870
871 This function reads per-hash algorithm information from standard
872 input (usually a heredoc) in the format described in
873 t/oid-info/README. This is useful for test-specific values, such as
874 object IDs, which must vary based on the hash algorithm.
875
876 Certain fixed values, such as hash sizes and common placeholder
877 object IDs, can be loaded with test_oid_init (described above).
878
879 - test_oid <key>
880
881 This function looks up a value for the hash algorithm in use, based
882 on the key given. The value must have been loaded using
883 test_oid_init or test_oid_cache. Providing an unknown key is an
884 error.
885
886 Prerequisites
887 -------------
888
889 These are the prerequisites that the test library predefines with
890 test_have_prereq.
891
892 See the prereq argument to the test_* functions in the "Test harness
893 library" section above and the "test_have_prereq" function for how to
894 use these, and "test_set_prereq" for how to define your own.
895
896 - PYTHON
897
898 Git wasn't compiled with NO_PYTHON=YesPlease. Wrap any tests that
899 need Python with this.
900
901 - PERL
902
903 Git wasn't compiled with NO_PERL=YesPlease.
904
905 Even without the PERL prerequisite, tests can assume there is a
906 usable perl interpreter at $PERL_PATH, though it need not be
907 particularly modern.
908
909 - POSIXPERM
910
911 The filesystem supports POSIX style permission bits.
912
913 - BSLASHPSPEC
914
915 Backslashes in pathspec are not directory separators. This is not
916 set on Windows. See 6fd1106a for details.
917
918 - EXECKEEPSPID
919
920 The process retains the same pid across exec(2). See fb9a2bea for
921 details.
922
923 - PIPE
924
925 The filesystem we're on supports creation of FIFOs (named pipes)
926 via mkfifo(1).
927
928 - SYMLINKS
929
930 The filesystem we're on supports symbolic links. E.g. a FAT
931 filesystem doesn't support these. See 704a3143 for details.
932
933 - SANITY
934
935 Test is not run by root user, and an attempt to write to an
936 unwritable file is expected to fail correctly.
937
938 - PCRE
939
940 Git was compiled with support for PCRE. Wrap any tests
941 that use git-grep --perl-regexp or git-grep -P in these.
942
943 - LIBPCRE1
944
945 Git was compiled with PCRE v1 support via
946 USE_LIBPCRE1=YesPlease. Wrap any PCRE using tests that for some
947 reason need v1 of the PCRE library instead of v2 in these.
948
949 - LIBPCRE2
950
951 Git was compiled with PCRE v2 support via
952 USE_LIBPCRE2=YesPlease. Wrap any PCRE using tests that for some
953 reason need v2 of the PCRE library instead of v1 in these.
954
955 - CASE_INSENSITIVE_FS
956
957 Test is run on a case insensitive file system.
958
959 - UTF8_NFD_TO_NFC
960
961 Test is run on a filesystem which converts decomposed utf-8 (nfd)
962 to precomposed utf-8 (nfc).
963
964 - PTHREADS
965
966 Git wasn't compiled with NO_PTHREADS=YesPlease.
967
968 Tips for Writing Tests
969 ----------------------
970
971 As with any programming projects, existing programs are the best
972 source of the information. However, do _not_ emulate
973 t0000-basic.sh when writing your tests. The test is special in
974 that it tries to validate the very core of GIT. For example, it
975 knows that there will be 256 subdirectories under .git/objects/,
976 and it knows that the object ID of an empty tree is a certain
977 40-byte string. This is deliberately done so in t0000-basic.sh
978 because the things the very basic core test tries to achieve is
979 to serve as a basis for people who are changing the GIT internal
980 drastically. For these people, after making certain changes,
981 not seeing failures from the basic test _is_ a failure. And
982 such drastic changes to the core GIT that even changes these
983 otherwise supposedly stable object IDs should be accompanied by
984 an update to t0000-basic.sh.
985
986 However, other tests that simply rely on basic parts of the core
987 GIT working properly should not have that level of intimate
988 knowledge of the core GIT internals. If all the test scripts
989 hardcoded the object IDs like t0000-basic.sh does, that defeats
990 the purpose of t0000-basic.sh, which is to isolate that level of
991 validation in one place. Your test also ends up needing
992 updating when such a change to the internal happens, so do _not_
993 do it and leave the low level of validation to t0000-basic.sh.
994
995 Test coverage
996 -------------
997
998 You can use the coverage tests to find code paths that are not being
999 used or properly exercised yet.
1000
1001 To do that, run the coverage target at the top-level (not in the t/
1002 directory):
1003
1004 make coverage
1005
1006 That'll compile Git with GCC's coverage arguments, and generate a test
1007 report with gcov after the tests finish. Running the coverage tests
1008 can take a while, since running the tests in parallel is incompatible
1009 with GCC's coverage mode.
1010
1011 After the tests have run you can generate a list of untested
1012 functions:
1013
1014 make coverage-untested-functions
1015
1016 You can also generate a detailed per-file HTML report using the
1017 Devel::Cover module. To install it do:
1018
1019 # On Debian or Ubuntu:
1020 sudo aptitude install libdevel-cover-perl
1021
1022 # From the CPAN with cpanminus
1023 curl -L http://cpanmin.us | perl - --sudo --self-upgrade
1024 cpanm --sudo Devel::Cover
1025
1026 Then, at the top-level:
1027
1028 make cover_db_html
1029
1030 That'll generate a detailed cover report in the "cover_db_html"
1031 directory, which you can then copy to a webserver, or inspect locally
1032 in a browser.