+ - test_set_prereq SOME_PREREQ
+
+ Set a test prerequisite to be used later with test_have_prereq. The
+ test-lib will set some prerequisites for you, e.g. PERL and PYTHON
+ which are derived from ./GIT-BUILD-OPTIONS (grep test_set_prereq
+ test-lib.sh for more). Others you can set yourself and use later
+ with either test_have_prereq directly, or the three argument
+ invocation of test_expect_success and test_expect_failure.
+
+ - test_have_prereq SOME PREREQ
+
+ Check if we have a prerequisite previously set with
+ test_set_prereq. The most common use of this directly is to skip
+ all the tests if we don't have some essential prerequisite:
+
+ if ! test_have_prereq PERL
+ then
+ skip_all='skipping perl interface tests, perl not available'
+ test_done
+ fi
+
+ - test_external [<prereq>] <message> <external> <script>
+
+ Execute a <script> with an <external> interpreter (like perl). This
+ was added for tests like t9700-perl-git.sh which do most of their
+ work in an external test script.
+
+ test_external \
+ 'GitwebCache::*FileCache*' \
+ "$PERL_PATH" "$TEST_DIRECTORY"/t9503/test_cache_interface.pl
+
+ If the test is outputting its own TAP you should set the
+ test_external_has_tap variable somewhere before calling the first
+ test_external* function. See t9700-perl-git.sh for an example.
+
+ # The external test will outputs its own plan
+ test_external_has_tap=1
+
+ - test_external_without_stderr [<prereq>] <message> <external> <script>
+
+ Like test_external but fail if there's any output on stderr,
+ instead of checking the exit code.
+
+ test_external_without_stderr \
+ 'Perl API' \
+ "$PERL_PATH" "$TEST_DIRECTORY"/t9700/test.pl
+
+ - test_must_fail <git-command>
+
+ Run a git command and ensure it fails in a controlled way. Use
+ this instead of "! <git-command>" to fail when git commands
+ segfault.
+
+ - test_might_fail <git-command>
+
+ Similar to test_must_fail, but tolerate success, too. Use this
+ instead of "<git-command> || :" to catch failures due to segv.
+
+ - test_cmp <expected> <actual>
+
+ Check whether the content of the <actual> file matches the
+ <expected> file. This behaves like "cmp" but produces more
+ helpful output when the test is run with "-v" option.
+
+ - test_when_finished <script>
+
+ Prepend <script> to a list of commands to run to clean up
+ at the end of the current test. If some clean-up command
+ fails, the test will not pass.
+
+ Example:
+
+ test_expect_success 'branch pointing to non-commit' '
+ git rev-parse HEAD^{tree} >.git/refs/heads/invalid &&
+ test_when_finished "git update-ref -d refs/heads/invalid" &&
+ ...
+ '
+
+