notmuch/test/README

Notmuch test suite
==================
This directory contains the test suite for notmuch.

When fixing bugs or enhancing notmuch, you are strongly encouraged to
add tests in this directory to cover what you are trying to fix or
enhance.

Running Tests
-------------
The easiest way to run tests is to say "make test", (or simply run the
notmuch-test script). Either command will run all available tests.

Alternately, you can run a specific subset of tests by simply invoking
one of the executable scripts in this directory, (such as ./search,
./reply, etc.)

The following command-line options are available when running tests:

--debug::
	This may help the person who is developing a new test.
	It causes the command defined with test_debug to run.

--immediate::
	This causes the test to immediately exit upon the first
	failed test.

--valgrind::
	Execute notmuch with valgrind and exit with status
	126 on errors (just like regular tests, this will only stop
	the test script when running under -i).  Valgrind errors
	go to stderr, so you might want to pass the -v option, too.

	Since it makes no sense to run the tests with --valgrind and
	not see any output, this option implies --verbose.  For
	convenience, it also implies --tee.

--tee::
	In addition to printing the test output to the terminal,
	write it to files named 't/test-results/$TEST_NAME.out'.
	As the names depend on the tests' file names, it is safe to
	run the tests with this option in parallel.

When invoking the test suite via "make test" any of the above options
can be specified as follows:

	make test OPTIONS="--verbose"

Skipping Tests
--------------
If, for any reason, you need to skip one or more tests, you can do so
by setting the NOTMUCH_SKIP_TESTS variable to the name of one or more
sections of tests.

For example:

    $ NOTMUCH_SKIP_TESTS="search reply" make test

Even more fine-grained skipping is possible by appending a test number
(or glob pattern) after the section name. For example, the first
search test and the second reply test could be skipped with:

    $ NOTMUCH_SKIP_TESTS="search.1 reply.2" make test

Note that some tests in the existing test suite rely on previous test
items, so you cannot arbitrarily skip any test and expect the
remaining tests to be unaffected.

Writing Tests
-------------
The test script is written as a shell script.  It should start
with the standard "#!/bin/bash" with copyright notices, and an
assignment to variable 'test_description', like this:

	#!/bin/bash
	#
	# Copyright (c) 2005 Junio C Hamano
	#

	test_description='xxx test (option --frotz)

	This test exercises the "notmuch xxx" command when
	given the option --frotz.'

Source 'test-lib.sh'
--------------------
After assigning test_description, the test script should source
test-lib.sh like this:

	. ./test-lib.sh

This test harness library does the following things:

 - If the script is invoked with command line argument --help
   (or -h), it shows the test_description and exits.

 - Creates a temporary directory with default notmuch-config and a
   mail store with a corpus of mail, (initially, 50 early messages
   sent to the notmuch list). This directory is
   test/tmp.<test-basename>. The path to notmuch-config is exported in
   NOTMUCH_CONFIG environment variable and mail store path is stored
   in MAIL_DIR variable.

 - Defines standard test helper functions for your scripts to
   use.  These functions are designed to make all scripts behave
   consistently when command line arguments --verbose (or -v),
   --debug (or -d), and --immediate (or -i) is given.

End with test_done
------------------
Your script will be a sequence of tests, using helper functions
from the test harness library.  At the end of the script, call
'test_done'.

Test harness library
--------------------
There are a handful helper functions defined in the test harness
library for your script to use.

 test_expect_success <message> <script>

   This takes two strings as parameter, and evaluates the
   <script>.  If it yields success, test is considered
   successful.  <message> should state what it is testing.

 test_expect_failure <message> <script>

   This is NOT the opposite of test_expect_success, but is used
   to mark a test that demonstrates a known breakage.  Unlike
   the usual test_expect_success tests, which say "ok" on
   success and "FAIL" on failure, this will say "FIXED" on
   success and "still broken" on failure.  Failures from these
   tests won't cause -i (immediate) to stop.

 test_begin_subtest <message>

   Set the test description message for a subsequent test_expect_equal
   invocation (see below).

 test_expect_equal <output> <expected>

   This is an often-used convenience function built on top of
   test_expect_success. It uses the message from the last
   test_begin_subtest call, so call before calling
   test_expect_equal. This function generates a successful test if
   both the <output> and <expected> strings are identical. If not, it
   will generate a failure and print the difference of the two
   strings.

 test_debug <script>

   This takes a single argument, <script>, and evaluates it only
   when the test script is started with --debug command line
   argument.  This is primarily meant for use during the
   development of a new test script.

 test_emacs <emacs-lisp-expressions>

   This function executes the provided emacs lisp script within
   emacs. The script can be a sequence of emacs lisp expressions,
   (that is, they will be evaluated within a progn form). The lisp
   expressions can call `message' to generate output on stdout to be
   examined by the calling test script.

 test_done

   Your test script must have test_done at the end.  Its purpose
   is to summarize successes and failures in the test script and
   exit with an appropriate error code.

There are also a number of mail-specific functions which are useful in
writing tests:

  generate_message

    Generates a message with an optional template. Most tests will
    actually prefere to call add_message. See below.

  add_message

    Generate a message and add it to the database (by calling "notmuch
    new"). It is sufficient to simply call add_message with no
    arguments if you don't care about the content of the message. If
    more control is needed, arguments can be provide to specify many
    different header values for the new message. See the documentation
    within test-lib.sh or refer to many example calls within existing
    tests.

  add_email_corpus

    This function should be called at the beginning of a test file
    when a test needs to operate on a non-empty body of messages. It
    will intialize the mail database to a known state of 50 sample
    messages, (culled from the early history of the notmuch mailing
    list).