tests: define GIT_TEST_PROTOCOL_VERSION
[git/git.git] / t / README
CommitLineData
986aa7f1
JH
1Core GIT Tests
2==============
3
4This directory holds many test scripts for core GIT tools. The
5first part of this short document describes how to run the tests
6and read their output.
7
8When fixing the tools or adding enhancements, you are strongly
9encouraged to add tests in this directory to cover what you are
10trying to fix or enhance. The later part of this short document
11describes how your test scripts should be organized.
12
13
14Running Tests
15-------------
16
17The easiest way to run tests is to say "make". This runs all
18the tests.
19
20 *** t0000-basic.sh ***
5099b99d
ÆAB
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
986aa7f1 24 ...
5099b99d
ÆAB
25 ok 43 - very long name in the index handled sanely
26 # fixed 1 known breakage(s)
27 # still have 1 known breakage(s)
28 # passed all remaining 42 test(s)
29 1..43
30 *** t0001-init.sh ***
31 ok 1 - plain
32 ok 2 - plain with GIT_WORK_TREE
33 ok 3 - plain bare
34
35Since the tests all output TAP (see http://testanything.org) they can
85b0b34e 36be run with any TAP harness. Here's an example of parallel testing
5099b99d
ÆAB
37powered by a recent version of prove(1):
38
39 $ prove --timer --jobs 15 ./t[0-9]*.sh
40 [19:17:33] ./t0005-signals.sh ................................... ok 36 ms
41 [19:17:33] ./t0022-crlf-rename.sh ............................... ok 69 ms
42 [19:17:33] ./t0024-crlf-archive.sh .............................. ok 154 ms
43 [19:17:33] ./t0004-unwritable.sh ................................ ok 289 ms
44 [19:17:33] ./t0002-gitfile.sh ................................... ok 480 ms
45 ===( 102;0 25/? 6/? 5/? 16/? 1/? 4/? 2/? 1/? 3/? 1... )===
46
47prove and other harnesses come with a lot of useful options. The
48--state option in particular is very useful:
49
50 # Repeat until no more failures
51 $ prove -j 15 --state=failed,save ./t[0-9]*.sh
986aa7f1 52
28d836c8
MG
53You can give DEFAULT_TEST_TARGET=prove on the make command (or define it
54in config.mak) to cause "make test" to run tests under prove.
55GIT_PROVE_OPTS can be used to pass additional options, e.g.
56
57 $ make DEFAULT_TEST_TARGET=prove GIT_PROVE_OPTS='--timer --jobs 16' test
58
5099b99d 59You can also run each test individually from command line, like this:
986aa7f1 60
5099b99d
ÆAB
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
986aa7f1
JH
69
70You can pass --verbose (or -v), --debug (or -d), and --immediate
4e1be63c
JS
71(or -i) command line argument to the test, or by setting GIT_TEST_OPTS
72appropriately before running "make".
986aa7f1 73
5e3b4fce 74-v::
986aa7f1
JH
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
ff09af3f
TR
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
a136f6d8
JK
85-x::
86 Turn on shell tracing (i.e., `set -x`) during the tests
94201a2b 87 themselves. Implies `--verbose`.
5fc98e79
SG
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.
a136f6d8 91
5e3b4fce 92-d::
986aa7f1
JH
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.
0986de94
PK
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.
986aa7f1 100
5e3b4fce 101-i::
986aa7f1
JH
102--immediate::
103 This causes the test to immediately exit upon the first
13cb3bb7
SR
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.
986aa7f1 108
5e3b4fce 109-l::
5e2c08c6
LW
110--long-tests::
111 This causes additional long-running tests to be run (where
112 available), for more exhaustive testing.
113
0445e6f0
IB
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
952af351
TR
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).
986aa7f1 124
3da93652
JS
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
952af351
TR
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
95d9d5ec
TR
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
952af351 139 Note that memcheck is run with the option --leak-check=no,
9aec68d3
CMN
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
5dfc368f
TR
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
44138559
JS
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
a5f52c6d 157-V::
452320f1
JK
158--verbose-log::
159 Write verbose output to the same logfile as `--tee`, but do
160 _not_ write it to stdout. Unlike `--tee --verbose`, this option
161 is safe to use when stdout is being consumed by a TAP parser
162 like `prove`. Implies `--tee` and `--verbose`.
163
e4597aae
MO
164--with-dashes::
165 By default tests are run without dashed forms of
166 commands (like git-commit) in the PATH (it only uses
167 wrappers from ../bin-wrappers). Use this option to include
168 the build directory (..) in the PATH, which contains all
169 the dashed forms of commands. This option is currently
170 implied by other options like --valgrind and
171 GIT_TEST_INSTALLED.
172
0d4dbcd3
TR
173--root=<directory>::
174 Create "trash" directories used to store all temporary data during
175 testing under <directory>, instead of the t/ directory.
176 Using this option with a RAM-based filesystem (such as tmpfs)
177 can massively speed up the test suite.
178
bb79af9d
JK
179--chain-lint::
180--no-chain-lint::
181 If --chain-lint is enabled, the test harness will check each
182 test to make sure that it properly "&&-chains" all commands (so
183 that a failure in the middle does not go unnoticed by the final
184 exit code of the test). This check is performed in addition to
185 running the tests themselves. You may also enable or disable
186 this feature by setting the GIT_TEST_CHAIN_LINT environment
187 variable to "1" or "0", respectively.
188
fb7d1e3a
SG
189--stress::
190--stress=<N>::
191 Run the test script repeatedly in multiple parallel jobs until
192 one of them fails. Useful for reproducing rare failures in
193 flaky tests. The number of parallel jobs is, in order of
194 precedence: <N>, or the value of the GIT_TEST_STRESS_LOAD
195 environment variable, or twice the number of available
196 processors (as shown by the 'getconf' utility), or 8.
197 Implies `--verbose -x --immediate` to get the most information
198 about the failure. Note that the verbose output of each test
199 job is saved to 't/test-results/$TEST_NAME.stress-<nr>.out',
200 and only the output of the failed test job is shown on the
201 terminal. The names of the trash directories get a
202 '.stress-<nr>' suffix, and the trash directory of the failed
203 test job is renamed to end with a '.stress-failed' suffix.
204
e160da7f
MO
205You can also set the GIT_TEST_INSTALLED environment variable to
206the bindir of an existing git installation to test that installation.
207You still need to have built this git sandbox, from which various
208test-* support programs, templates, and perl libraries are used.
209If your installed git is incomplete, it will silently test parts of
210your built version instead.
211
212When using GIT_TEST_INSTALLED, you can also set GIT_TEST_EXEC_PATH to
213override the location of the dashed-form subcommands (what
214GIT_EXEC_PATH would be used for during normal operation).
215GIT_TEST_EXEC_PATH defaults to `$GIT_TEST_INSTALLED/git --exec-path`.
216
217
fbd458a3
JN
218Skipping Tests
219--------------
220
221In some environments, certain tests have no way of succeeding
222due to platform limitation, such as lack of 'unzip' program, or
223filesystem that do not allow arbitrary sequence of non-NUL bytes
224as pathnames.
225
226You should be able to say something like
227
228 $ GIT_SKIP_TESTS=t9200.8 sh ./t9200-git-cvsexport-commit.sh
229
230and even:
231
232 $ GIT_SKIP_TESTS='t[0-4]??? t91?? t9200.8' make
233
234to omit such tests. The value of the environment variable is a
235SP separated list of patterns that tells which tests to skip,
236and either can match the "t[0-9]{4}" part to skip the whole
237test, or t[0-9]{4} followed by ".$number" to say which
238particular test to skip.
239
0445e6f0
IB
240For an individual test suite --run could be used to specify that
241only some tests should be run or that some tests should be
242excluded from a run.
243
244The argument for --run is a list of individual test numbers or
245ranges with an optional negation prefix that define what tests in
246a test suite to include in the run. A range is two numbers
247separated with a dash and matches a range of tests with both ends
248been included. You may omit the first or the second number to
249mean "from the first test" or "up to the very last test"
250respectively.
251
252Optional prefix of '!' means that the test or a range of tests
253should be excluded from the run.
254
255If --run starts with an unprefixed number or range the initial
256set of tests to run is empty. If the first item starts with '!'
257all the tests are added to the initial set. After initial set is
258determined every test number or range is added or excluded from
259the set one by one, from left to right.
260
261Individual numbers or ranges could be separated either by a space
262or a comma.
263
264For example, to run only tests up to a specific test (21), one
265could do this:
266
267 $ sh ./t9200-git-cvsexport-commit.sh --run='1-21'
268
269or this:
270
271 $ sh ./t9200-git-cvsexport-commit.sh --run='-21'
272
273Common case is to run several setup tests (1, 2, 3) and then a
274specific test (21) that relies on that setup:
275
276 $ sh ./t9200-git-cvsexport-commit.sh --run='1 2 3 21'
277
278or:
279
280 $ sh ./t9200-git-cvsexport-commit.sh --run=1,2,3,21
281
282or:
283
284 $ sh ./t9200-git-cvsexport-commit.sh --run='-3 21'
285
01e4be6c
KS
286As noted above, the test set is built by going through the items
287from left to right, so this:
0445e6f0
IB
288
289 $ sh ./t9200-git-cvsexport-commit.sh --run='1-4 !3'
290
01e4be6c 291will run tests 1, 2, and 4. Items that come later have higher
2e3a16b2 292precedence. It means that this:
0445e6f0
IB
293
294 $ sh ./t9200-git-cvsexport-commit.sh --run='!3 1-4'
295
296would just run tests from 1 to 4, including 3.
297
298You may use negation with ranges. The following will run all
299test in the test suite except from 7 up to 11:
300
301 $ sh ./t9200-git-cvsexport-commit.sh --run='!7-11'
302
303Some tests in a test suite rely on the previous tests performing
304certain actions, specifically some tests are designated as
305"setup" test, so you cannot _arbitrarily_ disable one test and
306expect the rest to function correctly.
307
308--run is mostly useful when you want to focus on a specific test
309and know what setup is needed for it. Or when you want to run
310everything up to a certain test.
fbd458a3
JN
311
312
4c2db938
NTND
313Running tests with special setups
314---------------------------------
315
316The whole test suite could be run to test some special features
317that cannot be easily covered by a few specific test cases. These
318could be enabled by running the test suite with correct GIT_TEST_
319environment set.
320
6cdccfce
ÆAB
321GIT_TEST_GETTEXT_POISON=<non-empty?> turns all strings marked for
322translation into gibberish if non-empty (think "test -n"). Used for
323spotting those tests that need to be marked with a C_LOCALE_OUTPUT
324prerequisite when adding more strings for translation. See "Testing
325marked strings" in po/README for details.
326
4c2db938
NTND
327GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole
328test suite. Accept any boolean values that are accepted by git-config.
329
8cbeba06
JT
330GIT_TEST_PROTOCOL_VERSION=<n>, when set, overrides the
331'protocol.version' setting to n if it is less than n.
332
43fa44fa
NTND
333GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon
334pack-objects code path where there are more than 1024 packs even if
335the actual number of packs in repository is below this limit. Accept
336any boolean values that are accepted by git-config.
337
ac77d0c3
NTND
338GIT_TEST_OE_SIZE=<n> exercises the uncommon pack-objects code path
339where we do not cache object size in memory and read it from existing
340packs on demand. This normally only happens when the object size is
341over 2GB. This variable forces the code path on any object larger than
342<n> bytes.
343
ac6e12f9 344GIT_TEST_OE_DELTA_SIZE=<n> exercises the uncommon pack-objects code
9ac3f0e5
NTND
345path where deltas larger than this limit require extra memory
346allocation for bookkeeping.
347
5f4436a7
NTND
348GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES=<boolean> checks that cache-tree
349records are valid when the index is written out or after a merge. This
350is mostly to catch missing invalidation. Default is true.
351
859fdc0c
DS
352GIT_TEST_COMMIT_GRAPH=<boolean>, when true, forces the commit-graph to
353be written after every 'git commit' command, and overrides the
354'core.commitGraph' setting to true.
355
4cb54d0a
BP
356GIT_TEST_FSMONITOR=$PWD/t7519/fsmonitor-all exercises the fsmonitor
357code path for utilizing a file system monitor to speed up detecting
358new or changed files.
359
1f357b04
BP
360GIT_TEST_INDEX_VERSION=<n> exercises the index read/write code path
361for the index version specified. Can be set to any valid version
362(currently 2, 3, or 4).
363
5765d97b
BP
364GIT_TEST_PRELOAD_INDEX=<boolean> exercises the preload-index code path
365by overriding the minimum number of cache entries required per thread.
366
62c23938
ÆAB
367GIT_TEST_REBASE_USE_BUILTIN=<boolean>, when false, disables the
368builtin version of git-rebase. See 'rebase.useBuiltin' in
369git-config(1).
370
c780b9cf
BP
371GIT_TEST_INDEX_THREADS=<n> enables exercising the multi-threaded loading
372of the index for the whole test suite by bypassing the default number of
373cache entries and thread minimums. Setting this to 1 will make the
374index loading single threaded.
375
0465a505
DS
376GIT_TEST_MULTI_PACK_INDEX=<boolean>, when true, forces the multi-pack-
377index to be written after every 'git repack' command, and overrides the
378'core.multiPackIndex' setting to true.
379
07c3c2aa
JT
380GIT_TEST_SIDEBAND_ALL=<boolean>, when true, overrides the
381'uploadpack.allowSidebandAll' setting to true, and when false, forces
382fetch-pack to not request sideband-all (even if the server advertises
383sideband-all).
384
f50c9f76
PB
385Naming Tests
386------------
387
388The test files are named as:
389
390 tNNNN-commandname-details.sh
391
392where N is a decimal digit.
393
394First digit tells the family:
395
396 0 - the absolute basics and global stuff
397 1 - the basic commands concerning database
398 2 - the basic commands concerning the working tree
399 3 - the other basic commands (e.g. ls-files)
400 4 - the diff commands
401 5 - the pull and exporting commands
402 6 - the revision tree commands (even e.g. merge-base)
8f4a9b62 403 7 - the porcelainish commands concerning the working tree
8757749e
JN
404 8 - the porcelainish commands concerning forensics
405 9 - the git tools
f50c9f76
PB
406
407Second digit tells the particular command we are testing.
408
409Third digit (optionally) tells the particular switch or group of switches
410we are testing.
411
77656600
JH
412If you create files under t/ directory (i.e. here) that is not
413the top-level test script, never name the file to match the above
414pattern. The Makefile here considers all such files as the
63d32945 415top-level test script and tries to run all of them. Care is
77656600
JH
416especially needed if you are creating a common test library
417file, similar to test-lib.sh, because such a library file may
418not be suitable for standalone execution.
419
f50c9f76 420
986aa7f1
JH
421Writing Tests
422-------------
423
424The test script is written as a shell script. It should start
51b7a525 425with the standard "#!/bin/sh", and an
986aa7f1
JH
426assignment to variable 'test_description', like this:
427
428 #!/bin/sh
986aa7f1 429
14cd1ff3 430 test_description='xxx test (option --frotz)
986aa7f1
JH
431
432 This test registers the following structure in the cache
433 and tries to run git-ls-files with option --frotz.'
434
f50c9f76 435
986aa7f1
JH
436Source 'test-lib.sh'
437--------------------
438
439After assigning test_description, the test script should source
440test-lib.sh like this:
441
442 . ./test-lib.sh
443
444This test harness library does the following things:
445
446 - If the script is invoked with command line argument --help
447 (or -h), it shows the test_description and exits.
448
e1ca1c9d
ÆAB
449 - Creates an empty test directory with an empty .git/objects database
450 and chdir(2) into it. This directory is 't/trash
451 directory.$test_name_without_dotsh', with t/ subject to change by
fb7d1e3a
SG
452 the --root option documented above, and a '.stress-<N>' suffix
453 appended by the --stress option.
986aa7f1
JH
454
455 - Defines standard test helper functions for your scripts to
456 use. These functions are designed to make all scripts behave
457 consistently when command line arguments --verbose (or -v),
458 --debug (or -d), and --immediate (or -i) is given.
459
441ee35d
MD
460Do's & don'ts
461-------------
20873f45 462
6fd45295 463Here are a few examples of things you probably should and shouldn't do
20873f45
ÆAB
464when writing tests.
465
441ee35d 466Here are the "do's:"
20873f45 467
6fd45295 468 - Put all code inside test_expect_success and other assertions.
20873f45
ÆAB
469
470 Even code that isn't a test per se, but merely some setup code
6fd45295 471 should be inside a test assertion.
20873f45
ÆAB
472
473 - Chain your test assertions
474
475 Write test code like this:
476
477 git merge foo &&
478 git push bar &&
479 test ...
480
481 Instead of:
482
483 git merge hla
484 git push gh
485 test ...
486
487 That way all of the commands in your tests will succeed or fail. If
00648ba0
EN
488 you must ignore the return value of something, consider using a
489 helper function (e.g. use sane_unset instead of unset, in order
490 to avoid unportable return value for unsetting a variable that was
491 already unset), or prepending the command with test_might_fail or
492 test_must_fail.
20873f45 493
0c357544
ÆAB
494 - Check the test coverage for your tests. See the "Test coverage"
495 below.
496
63d32945
MW
497 Don't blindly follow test coverage metrics; if a new function you added
498 doesn't have any coverage, then you're probably doing something wrong,
e8b55f5c
ÆAB
499 but having 100% coverage doesn't necessarily mean that you tested
500 everything.
501
502 Tests that are likely to smoke out future regressions are better
503 than tests that just inflate the coverage metrics.
504
95b104c8
JS
505 - When a test checks for an absolute path that a git command generated,
506 construct the expected value using $(pwd) rather than $PWD,
507 $TEST_DIRECTORY, or $TRASH_DIRECTORY. It makes a difference on
508 Windows, where the shell (MSYS bash) mangles absolute path names.
509 For details, see the commit message of 4114156ae9.
510
441ee35d
MD
511 - Remember that inside the <script> part, the standard output and
512 standard error streams are discarded, and the test harness only
513 reports "ok" or "not ok" to the end user running the tests. Under
514 --verbose, they are shown to help debug the tests.
515
516And here are the "don'ts:"
20873f45 517
441ee35d 518 - Don't exit() within a <script> part.
20873f45
ÆAB
519
520 The harness will catch this as a programming error of the test.
521 Use test_done instead if you need to stop the tests early (see
522 "Skipping tests" below).
523
441ee35d
MD
524 - Don't use '! git cmd' when you want to make sure the git command
525 exits with failure in a controlled way by calling "die()". Instead,
ad78585e
JH
526 use 'test_must_fail git cmd'. This will signal a failure if git
527 dies in an unexpected way (e.g. segfault).
528
f445500e 529 On the other hand, don't use test_must_fail for running regular
53de7424
JH
530 platform commands; just use '! cmd'. We are not in the business
531 of verifying that the world given to us sanely works.
f445500e 532
a378fee5
MD
533 - Don't feed the output of a git command to a pipe, as in:
534
535 git -C repo ls-files |
536 xargs -n 1 basename |
537 grep foo
538
539 which will discard git's exit code and may mask a crash. In the
540 above example, all exit codes are ignored except grep's.
541
542 Instead, write the output of that command to a temporary
543 file with ">" or assign it to a variable with "x=$(git ...)" rather
544 than pipe it.
545
546 - Don't use command substitution in a way that discards git's exit
547 code. When assigning to a variable, the exit code is not discarded,
548 e.g.:
549
550 x=$(git cat-file -p $sha) &&
551 ...
552
553 is OK because a crash in "git cat-file" will cause the "&&" chain
554 to fail, but:
555
556 test "refs/heads/foo" = "$(git symbolic-ref HEAD)"
557
558 is not OK and a crash in git could go undetected.
559
441ee35d
MD
560 - Don't use perl without spelling it as "$PERL_PATH". This is to help
561 our friends on Windows where the platform Perl often adds CR before
ad78585e 562 the end of line, and they bundle Git with a version of Perl that
a0e0ec9f
JK
563 does not do so, whose path is specified with $PERL_PATH. Note that we
564 provide a "perl" function which uses $PERL_PATH under the hood, so
565 you do not need to worry when simply running perl in the test scripts
566 (but you do, for example, on a shebang line or in a sub script
567 created via "write_script").
ad78585e 568
441ee35d
MD
569 - Don't use sh without spelling it as "$SHELL_PATH", when the script
570 can be misinterpreted by broken platform shell (e.g. Solaris).
ad78585e 571
441ee35d 572 - Don't chdir around in tests. It is not sufficient to chdir to
ad78585e
JH
573 somewhere and then chdir back to the original location later in
574 the test, as any intermediate step can fail and abort the test,
575 causing the next test to start in an unexpected directory. Do so
576 inside a subshell if necessary.
577
441ee35d
MD
578 - Don't save and verify the standard error of compound commands, i.e.
579 group commands, subshells, and shell functions (except test helper
94201a2b
SG
580 functions like 'test_must_fail') like this:
581
582 ( cd dir && git cmd ) 2>error &&
583 test_cmp expect error
584
585 When running the test with '-x' tracing, then the trace of commands
586 executed in the compound command will be included in standard error
587 as well, quite possibly throwing off the subsequent checks examining
588 the output. Instead, save only the relevant git command's standard
589 error:
590
591 ( cd dir && git cmd 2>../error ) &&
592 test_cmp expect error
593
441ee35d 594 - Don't break the TAP output
20873f45 595
6fd45295
JH
596 The raw output from your test may be interpreted by a TAP harness. TAP
597 harnesses will ignore everything they don't know about, but don't step
598 on their toes in these areas:
20873f45
ÆAB
599
600 - Don't print lines like "$x..$y" where $x and $y are integers.
601
602 - Don't print lines that begin with "ok" or "not ok".
603
6fd45295 604 TAP harnesses expect a line that begins with either "ok" and "not
20873f45
ÆAB
605 ok" to signal a test passed or failed (and our harness already
606 produces such lines), so your script shouldn't emit such lines to
607 their output.
608
609 You can glean some further possible issues from the TAP grammar
c1d44cee 610 (see https://metacpan.org/pod/TAP::Parser::Grammar#TAP-GRAMMAR)
20873f45
ÆAB
611 but the best indication is to just run the tests with prove(1),
612 it'll complain if anything is amiss.
613
20873f45 614
b5500d16
ÆAB
615Skipping tests
616--------------
617
681186ae 618If you need to skip tests you should do so by using the three-arg form
99d9050d
ÆAB
619of the test_* functions (see the "Test harness library" section
620below), e.g.:
621
ad78585e 622 test_expect_success PERL 'I need Perl' '
a0e0ec9f 623 perl -e "hlagh() if unf_unf()"
ad78585e 624 '
99d9050d
ÆAB
625
626The advantage of skipping tests like this is that platforms that don't
627have the PERL and other optional dependencies get an indication of how
628many tests they're missing.
629
630If the test code is too hairy for that (i.e. does a lot of setup work
631outside test assertions) you can also skip all remaining tests by
632setting skip_all and immediately call test_done:
b5500d16
ÆAB
633
634 if ! test_have_prereq PERL
635 then
636 skip_all='skipping perl interface tests, perl not available'
637 test_done
638 fi
14cd1ff3 639
99d9050d
ÆAB
640The string you give to skip_all will be used as an explanation for why
641the test was skipped.
642
986aa7f1
JH
643End with test_done
644------------------
645
646Your script will be a sequence of tests, using helper functions
647from the test harness library. At the end of the script, call
648'test_done'.
649
650
651Test harness library
652--------------------
653
654There are a handful helper functions defined in the test harness
655library for your script to use.
656
9a897893 657 - test_expect_success [<prereq>] <message> <script>
986aa7f1 658
72942a61 659 Usually takes two strings as parameters, and evaluates the
986aa7f1
JH
660 <script>. If it yields success, test is considered
661 successful. <message> should state what it is testing.
662
663 Example:
664
665 test_expect_success \
666 'git-write-tree should be able to write an empty tree.' \
667 'tree=$(git-write-tree)'
668
9a897893 669 If you supply three parameters the first will be taken to be a
72942a61 670 prerequisite; see the test_set_prereq and test_have_prereq
9a897893
ÆAB
671 documentation below:
672
673 test_expect_success TTY 'git --paginate rev-list uses a pager' \
674 ' ... '
675
93a57246
ÆAB
676 You can also supply a comma-separated list of prerequisites, in the
677 rare case where your test depends on more than one:
678
679 test_expect_success PERL,PYTHON 'yo dawg' \
680 ' test $(perl -E 'print eval "1 +" . qx[python -c "print 2"]') == "4" '
681
9a897893 682 - test_expect_failure [<prereq>] <message> <script>
986aa7f1 683
41ac414e
JH
684 This is NOT the opposite of test_expect_success, but is used
685 to mark a test that demonstrates a known breakage. Unlike
686 the usual test_expect_success tests, which say "ok" on
687 success and "FAIL" on failure, this will say "FIXED" on
688 success and "still broken" on failure. Failures from these
689 tests won't cause -i (immediate) to stop.
986aa7f1 690
9a897893
ÆAB
691 Like test_expect_success this function can optionally use a three
692 argument invocation with a prerequisite as the first argument.
693
986aa7f1
JH
694 - test_debug <script>
695
696 This takes a single argument, <script>, and evaluates it only
697 when the test script is started with --debug command line
698 argument. This is primarily meant for use during the
699 development of a new test script.
700
6a94088c
JS
701 - debug <git-command>
702
703 Run a git command inside a debugger. This is primarily meant for
704 use when debugging a failing test script.
705
986aa7f1
JH
706 - test_done
707
708 Your test script must have test_done at the end. Its purpose
709 is to summarize successes and failures in the test script and
710 exit with an appropriate error code.
711
00884968
JS
712 - test_tick
713
714 Make commit and tag names consistent by setting the author and
63d32945 715 committer times to defined state. Subsequent calls will
00884968
JS
716 advance the times by a fixed amount.
717
718 - test_commit <message> [<filename> [<contents>]]
719
720 Creates a commit with the given message, committing the given
721 file with the given contents (default for both is to reuse the
722 message string), and adds a tag (again reusing the message
723 string as name). Calls test_tick to make the SHA-1s
724 reproducible.
725
726 - test_merge <message> <commit-or-tag>
727
728 Merges the given rev using the given message. Like test_commit,
729 creates a tag and calls test_tick before committing.
986aa7f1 730
72942a61 731 - test_set_prereq <prereq>
9a897893
ÆAB
732
733 Set a test prerequisite to be used later with test_have_prereq. The
be53deef
ÆAB
734 test-lib will set some prerequisites for you, see the
735 "Prerequisites" section below for a full list of these.
736
737 Others you can set yourself and use later with either
738 test_have_prereq directly, or the three argument invocation of
739 test_expect_success and test_expect_failure.
9a897893 740
72942a61 741 - test_have_prereq <prereq>
9a897893 742
4473060b
ÆAB
743 Check if we have a prerequisite previously set with test_set_prereq.
744 The most common way to use this explicitly (as opposed to the
745 implicit use when an argument is passed to test_expect_*) is to skip
746 all the tests at the start of the test script if we don't have some
747 essential prerequisite:
9a897893
ÆAB
748
749 if ! test_have_prereq PERL
750 then
751 skip_all='skipping perl interface tests, perl not available'
752 test_done
753 fi
754
2fac6a4b
ÆAB
755 - test_external [<prereq>] <message> <external> <script>
756
757 Execute a <script> with an <external> interpreter (like perl). This
758 was added for tests like t9700-perl-git.sh which do most of their
759 work in an external test script.
760
761 test_external \
762 'GitwebCache::*FileCache*' \
a0e0ec9f 763 perl "$TEST_DIRECTORY"/t9503/test_cache_interface.pl
2fac6a4b
ÆAB
764
765 If the test is outputting its own TAP you should set the
766 test_external_has_tap variable somewhere before calling the first
767 test_external* function. See t9700-perl-git.sh for an example.
768
769 # The external test will outputs its own plan
770 test_external_has_tap=1
771
772 - test_external_without_stderr [<prereq>] <message> <external> <script>
773
774 Like test_external but fail if there's any output on stderr,
775 instead of checking the exit code.
776
777 test_external_without_stderr \
778 'Perl API' \
a0e0ec9f 779 perl "$TEST_DIRECTORY"/t9700/test.pl
2fac6a4b 780
892e6f7e
ÆAB
781 - test_expect_code <exit-code> <command>
782
783 Run a command and ensure that it exits with the given exit code.
784 For example:
785
786 test_expect_success 'Merge with d/f conflicts' '
787 test_expect_code 1 git merge "merge msg" B master
788 '
789
12e31a6b 790 - test_must_fail [<options>] <git-command>
c9667456
JN
791
792 Run a git command and ensure it fails in a controlled way. Use
971ecbd1
BC
793 this instead of "! <git-command>". When git-command dies due to a
794 segfault, test_must_fail diagnoses it as an error; "! <git-command>"
795 treats it as just another expected failure, which would let such a
796 bug go unnoticed.
c9667456 797
12e31a6b
SG
798 Accepts the following options:
799
800 ok=<signal-name>[,<...>]:
801 Don't treat an exit caused by the given signal as error.
802 Multiple signals can be specified as a comma separated list.
803 Currently recognized signal names are: sigpipe, success.
804 (Don't use 'success', use 'test_might_fail' instead.)
805
806 - test_might_fail [<options>] <git-command>
c9667456
JN
807
808 Similar to test_must_fail, but tolerate success, too. Use this
809 instead of "<git-command> || :" to catch failures due to segv.
810
12e31a6b
SG
811 Accepts the same options as test_must_fail.
812
c9667456
JN
813 - test_cmp <expected> <actual>
814
815 Check whether the content of the <actual> file matches the
816 <expected> file. This behaves like "cmp" but produces more
817 helpful output when the test is run with "-v" option.
818
5a052626
TG
819 - test_cmp_rev <expected> <actual>
820
821 Check whether the <expected> rev points to the same commit as the
822 <actual> rev.
823
fb3340a6
JN
824 - test_line_count (= | -lt | -ge | ...) <length> <file>
825
826 Check whether a file has the length it is expected to.
827
72942a61
ML
828 - test_path_is_file <path> [<diagnosis>]
829 test_path_is_dir <path> [<diagnosis>]
2caf20c5
MM
830 test_path_is_missing <path> [<diagnosis>]
831
72942a61
ML
832 Check if the named path is a file, if the named path is a
833 directory, or if the named path does not exist, respectively,
834 and fail otherwise, showing the <diagnosis> text.
2caf20c5 835
c9667456
JN
836 - test_when_finished <script>
837
838 Prepend <script> to a list of commands to run to clean up
839 at the end of the current test. If some clean-up command
840 fails, the test will not pass.
841
842 Example:
843
844 test_expect_success 'branch pointing to non-commit' '
845 git rev-parse HEAD^{tree} >.git/refs/heads/invalid &&
846 test_when_finished "git update-ref -d refs/heads/invalid" &&
847 ...
848 '
849
bb98b01e 850 - test_write_lines <lines>
ac9afcc3 851
bb98b01e 852 Write <lines> on standard output, one line per argument.
ac9afcc3
MT
853 Useful to prepare multi-line files in a compact form.
854
855 Example:
856
bb98b01e 857 test_write_lines a b c d e f g >foo
ac9afcc3
MT
858
859 Is a more compact equivalent of:
860 cat >foo <<-EOF
861 a
862 b
863 c
864 d
865 e
866 f
867 g
868 EOF
869
870
c4d2539a
JL
871 - test_pause
872
873 This command is useful for writing and debugging tests and must be
874 removed before submitting. It halts the execution of the test and
875 spawns a shell in the trash directory. Exit the shell to continue
876 the test. Example:
877
878 test_expect_success 'test' '
879 git do-something >actual &&
880 test_pause &&
881 test_cmp expected actual
882 '
883
9ce415d9
JS
884 - test_ln_s_add <path1> <path2>
885
886 This function helps systems whose filesystem does not support symbolic
887 links. Use it to add a symbolic link entry to the index when it is not
888 important that the file system entry is a symbolic link, i.e., instead
889 of the sequence
890
891 ln -s foo bar &&
892 git add bar
893
894 Sometimes it is possible to split a test in a part that does not need
895 the symbolic link in the file system and a part that does; then only
896 the latter part need be protected by a SYMLINKS prerequisite (see below).
897
2c02b110 898 - test_oid_init
899
900 This function loads facts and useful object IDs related to the hash
901 algorithm(s) in use from the files in t/oid-info.
902
903 - test_oid_cache
904
905 This function reads per-hash algorithm information from standard
906 input (usually a heredoc) in the format described in
907 t/oid-info/README. This is useful for test-specific values, such as
908 object IDs, which must vary based on the hash algorithm.
909
910 Certain fixed values, such as hash sizes and common placeholder
911 object IDs, can be loaded with test_oid_init (described above).
912
913 - test_oid <key>
914
915 This function looks up a value for the hash algorithm in use, based
916 on the key given. The value must have been loaded using
917 test_oid_init or test_oid_cache. Providing an unknown key is an
918 error.
919
be53deef
ÆAB
920Prerequisites
921-------------
922
923These are the prerequisites that the test library predefines with
924test_have_prereq.
925
926See the prereq argument to the test_* functions in the "Test harness
927library" section above and the "test_have_prereq" function for how to
928use these, and "test_set_prereq" for how to define your own.
929
f8fc0ee3 930 - PYTHON
be53deef 931
f8fc0ee3
JN
932 Git wasn't compiled with NO_PYTHON=YesPlease. Wrap any tests that
933 need Python with this.
934
935 - PERL
936
937 Git wasn't compiled with NO_PERL=YesPlease.
938
939 Even without the PERL prerequisite, tests can assume there is a
940 usable perl interpreter at $PERL_PATH, though it need not be
941 particularly modern.
be53deef
ÆAB
942
943 - POSIXPERM
944
945 The filesystem supports POSIX style permission bits.
946
947 - BSLASHPSPEC
948
949 Backslashes in pathspec are not directory separators. This is not
950 set on Windows. See 6fd1106a for details.
951
952 - EXECKEEPSPID
953
954 The process retains the same pid across exec(2). See fb9a2bea for
955 details.
956
20073274
AS
957 - PIPE
958
959 The filesystem we're on supports creation of FIFOs (named pipes)
960 via mkfifo(1).
961
be53deef
ÆAB
962 - SYMLINKS
963
964 The filesystem we're on supports symbolic links. E.g. a FAT
965 filesystem doesn't support these. See 704a3143 for details.
2fac6a4b 966
c91cfd19
ÆAB
967 - SANITY
968
969 Test is not run by root user, and an attempt to write to an
970 unwritable file is expected to fail correctly.
2fac6a4b 971
3eb585c1 972 - PCRE
8f852ce6 973
3eb585c1 974 Git was compiled with support for PCRE. Wrap any tests
8f852ce6
MK
975 that use git-grep --perl-regexp or git-grep -P in these.
976
ce9a2570
ÆAB
977 - LIBPCRE1
978
979 Git was compiled with PCRE v1 support via
980 USE_LIBPCRE1=YesPlease. Wrap any PCRE using tests that for some
981 reason need v1 of the PCRE library instead of v2 in these.
982
983 - LIBPCRE2
984
985 Git was compiled with PCRE v2 support via
986 USE_LIBPCRE2=YesPlease. Wrap any PCRE using tests that for some
987 reason need v2 of the PCRE library instead of v1 in these.
988
ac39aa61
MG
989 - CASE_INSENSITIVE_FS
990
991 Test is run on a case insensitive file system.
992
5b0b5dd4
MG
993 - UTF8_NFD_TO_NFC
994
995 Test is run on a filesystem which converts decomposed utf-8 (nfd)
996 to precomposed utf-8 (nfc).
997
68c7d276
ÆAB
998 - PTHREADS
999
1000 Git wasn't compiled with NO_PTHREADS=YesPlease.
1001
986aa7f1
JH
1002Tips for Writing Tests
1003----------------------
1004
1005As with any programming projects, existing programs are the best
1006source of the information. However, do _not_ emulate
1007t0000-basic.sh when writing your tests. The test is special in
1008that it tries to validate the very core of GIT. For example, it
1009knows that there will be 256 subdirectories under .git/objects/,
1010and it knows that the object ID of an empty tree is a certain
101140-byte string. This is deliberately done so in t0000-basic.sh
1012because the things the very basic core test tries to achieve is
1013to serve as a basis for people who are changing the GIT internal
1014drastically. For these people, after making certain changes,
1015not seeing failures from the basic test _is_ a failure. And
1016such drastic changes to the core GIT that even changes these
1017otherwise supposedly stable object IDs should be accompanied by
1018an update to t0000-basic.sh.
1019
1020However, other tests that simply rely on basic parts of the core
1021GIT working properly should not have that level of intimate
1022knowledge of the core GIT internals. If all the test scripts
1023hardcoded the object IDs like t0000-basic.sh does, that defeats
1024the purpose of t0000-basic.sh, which is to isolate that level of
1025validation in one place. Your test also ends up needing
1026updating when such a change to the internal happens, so do _not_
1027do it and leave the low level of validation to t0000-basic.sh.
d15e9ebc 1028
0c357544
ÆAB
1029Test coverage
1030-------------
1031
1032You can use the coverage tests to find code paths that are not being
1033used or properly exercised yet.
1034
1035To do that, run the coverage target at the top-level (not in the t/
1036directory):
1037
1038 make coverage
1039
1040That'll compile Git with GCC's coverage arguments, and generate a test
1041report with gcov after the tests finish. Running the coverage tests
1042can take a while, since running the tests in parallel is incompatible
1043with GCC's coverage mode.
1044
1045After the tests have run you can generate a list of untested
1046functions:
1047
1048 make coverage-untested-functions
1049
1050You can also generate a detailed per-file HTML report using the
1051Devel::Cover module. To install it do:
1052
1053 # On Debian or Ubuntu:
1054 sudo aptitude install libdevel-cover-perl
1055
1056 # From the CPAN with cpanminus
1057 curl -L http://cpanmin.us | perl - --sudo --self-upgrade
1058 cpanm --sudo Devel::Cover
1059
1060Then, at the top-level:
1061
1062 make cover_db_html
1063
1064That'll generate a detailed cover report in the "cover_db_html"
1065directory, which you can then copy to a webserver, or inspect locally
1066in a browser.