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 Cram: It's test time

Cram is a functional testing framework for command line applications
based on Mercurial_'s `unified test format`_.

Cram tests look like snippets of interactive shell sessions. Cram runs
each command and compares the command output in the test with the
command's actual output.

Here's a snippet from `Cram's own test suite`_::

    The $PYTHON environment variable should be set when running this test
    from Python.

      $ [ -n "$PYTHON" ] || PYTHON="`which python`"
      $ if [ -n "$COVERAGE" ]; then
      >   coverage erase
      >   alias cram="`which coverage` run --branch -a $TESTDIR/../"
      > else
      >   alias cram="$PYTHON $TESTDIR/../"
      > fi
      $ command -v md5 > /dev/null || alias md5=md5sum


      $ cram -h
      [Uu]sage: cram \[OPTIONS\] TESTS\.\.\. (re)

      [Oo]ptions: (re)
        -h, --help          show this help message and exit
        -V, --version       show version information and exit
        -q, --quiet         don't print diffs
        -v, --verbose       show filenames and test status
        -i, --interactive   interactively merge changed test output
        -y, --yes           answer yes to all questions
        -n, --no            answer no to all questions
        -E, --preserve-env  don't reset common environment variables
        --keep-tmpdir       keep temporary directories
        --shell=PATH        shell to use for running tests
        --indent=NUM        number of spaces to use for indentation

The format in a nutshell:

* Cram tests use the ``.t`` file extension.

* Lines beginning with two spaces, a dollar sign, and a space are run
  in the shell.

* Lines beginning with two spaces, a greater than sign, and a space
  allow multi-line commands.

* All other lines beginning with two spaces are considered command

* Output lines ending with a space and the keyword ``(re)`` are
  matched as `Perl-compatible regular expressions`_.

* Lines ending with a space and the keyword ``(glob)`` are matched
  with a glob-like syntax. The only special characters supported are
  ``*`` and ``?``. Both characters can be escaped using ``\``, and the
  backslash can be escaped itself.

* Output lines ending with either of the above keywords are always
  first matched literally with actual command output.

* Lines ending with a space and the keyword ``(no-eol)`` will match
  actual output that doesn't end in a newline.

* Actual output lines containing unprintable characters are escaped
  and suffixed with a space and the keyword ``(esc)``. Lines matching
  unprintable output must also contain the keyword.

* Anything else is a comment.

.. _Mercurial:
.. _unified test format:
.. _Cram's own test suite:
.. _Perl-compatible regular expressions:


* cram-0.5.tar.gz_ (22 KB, requires Python 2.4-2.7 or Python 3.1-3.2)

.. _cram-0.5.tar.gz:


You can use pip_ to install Cram::

    $ pip install cram

Or you can install Cram the old fashioned way::

    $ wget
    $ tar zxvf cram-0.5.tar.gz
    $ cd cram-0.5.tar.gz
    $ python install

.. _pip:


Cram will print a dot for each passing test. If a test fails, a
`unified context diff`_ is printed showing the test's expected output
and the actual output. Skipped tests (empty tests and tests that exit
with return code ``80``) are marked with ``s`` instead of a dot.

For example, if we run Cram on `its own example tests`_::

    --- /home/brodie/src/cram/examples/fail.t
    +++ /home/brodie/src/cram/examples/fail.t.err
    @@ -3,21 +3,22 @@
       $ echo 1
       $ echo 1
    -  2
    +  1
       $ echo 1

     Invalid regex:

       $ echo 1
    -  +++ (re)
    +  1

     Offset regular expression:

       $ printf 'foo\nbar\nbaz\n\n1\nA\n@\n'
    +  bar

       \d (re)
       [A-Z] (re)
    -  #
    +  @
    # Ran 6 tests, 2 skipped, 1 failed.

Cram will also write the test with its actual output to

When you're first writing a test, you might just write the commands
and run the test to see what happens. If you run Cram with ``-i`` or
``--interactive``, you'll be prompted to merge the actual output back
into the test. This makes it easy to quickly prototype new tests.

You can specify a default set of options by creating a ``.cramrc``
file. For example::

    verbose = True
    indent = 4

Is the same as invoking Cram with ``--verbose`` and ``--indent=4``.

To change what configuration file Cram loads, you can set the
``CRAMRC`` environment variable. You can also specify command line
options in the ``CRAM`` environment variable.

Note that the following environment variables are reset before tests
are run:

* ``TMPDIR``, ``TEMP``, and ``TMP`` are set to the test runner's
  ``tmp`` directory.

* ``LANG``, ``LC_ALL``, and ``LANGUAGE`` are set to ``C``.

* ``TZ`` is set to ``GMT``.

* ``COLUMNS`` is set to ``80``.

* ``CDPATH`` and ``GREP_OPTIONS`` are set to an empty string.

Cram also provides the following environment variables to tests:

* ``CRAMTMP``, set to the test runner's temporary directory.

* ``TESTDIR``, set to the directory containing the test file.

.. _unified context diff:
.. _its own example tests:


Version 0.6
* Added support for specifying options in ``.cramrc`` (configurable
  with the ``CRAMRC`` environment variable).

* Added a ``--shell`` option to change the shell tests are run
  with. Contributed by `Kamil Kisiel`_.

* Added the long option ``--preserve-env`` for ``-E``.

.. _Kamil Kisiel:

Version 0.5 (Jan. 8, 2011)
* **The test format has changed:** Matching output not ending in a
  newline now requires the ``(no-eol)`` keyword instead of ending the
  line in ``%``.

* Matching output containing unprintable characters now requires the
  ``(esc)`` keyword. Real output containing unprintable characters
  will automatically receive ``(esc)``.

* If an expected line matches its real output line exactly, special
  matching like ``(re)`` or ``(glob)`` will be ignored.

* Regular expressions ending in a trailing backslash are now
  considered invalid.

* Added an ``--indent`` option for changing the default amount of
  indentation required to specify commands and output.

* Added support for specifying command line options in the ``CRAM``
  environment variable.

* The ``--quiet`` and ``--verbose`` options can now be used together.

* When running Cram under Python 3, Unicode-specific line break
  characters will no longer be parsed as newlines.

* Tests are no longer required to end in a trailing newline.

Version 0.4 (Sep. 28, 2010)
* **The test format has changed:** Output lines containing regular
  expressions must now end in ``(re)`` or they'll be matched
  literally. Lines ending with keywords are matched literally first,

* Regular expressions are now matched from beginning to end. In other
  words ``\d (re)`` is matched as ``^\d$``.

* In addition to ``(re)``, ``(glob)`` has been added. It supports
  ``*``, ``?``, and escaping both characters (and backslashes) using

* **Environment settings have changed:** The ``-D`` flag has been
  removed, ``$TESTDIR`` is now set to the directory containing the
  ``.t`` file, and ``$CRAMTMP`` is set to the test runner's temporary

* ``-i``/``--interactive`` now requires ``patch(1)``. Instead of
  ``.err`` files replacing ``.t`` files during merges, diffs are
  applied using ``patch(1)``. This prevents matching regular
  expressions and globs from getting clobbered.

* Previous ``.err`` files are now removed when tests pass.

* Cram now exits with return code ``1`` if any tests failed.

* If a test exits with return code ``80``, it's considered a skipped a
  test. This is useful for intentionally disabling tests when they
  only work on certain platforms or in certain settings.

* The number of tests, the number of skipped tests, and the number of
  failed tests are now printed after all tests are finished.

* Added ``-q``/``--quiet`` to suppress diff output.

* Added `contrib/cram.vim`_ syntax file for Vim. Contributed by `Steve

.. _contrib/cram.vim:
.. _Steve Losh:

Version 0.3 (Sep. 20, 2010)
* Implemented resetting of common environment variables. This behavior
  can be disabled using the ``-E`` flag.

* Changed the test runner to first make its own overall random
  temporary directory, make ``tmp`` inside of it and set ``TMPDIR``,
  etc. to its path, and run each test with a random temporary working
  directory inside of that.

* Added ``--keep-tmpdir``. Temporary directories are named by test
  filename (along with a random string).

* Added ``-i``/``--interactive`` to merge actual output back to into
  tests interactively.

* Added ability to match command output not ending in a newline by
  suffixing output in the test with ``%``.

Version 0.2 (Sep. 19, 2010)
* Changed the test runner to run tests with a random temporary working

Version 0.1 (Sep. 19, 2010)
* Initial release.


Download the official development repository using Mercurial_::

    hg clone

Test Cram using Cram::

    make tests

Get a test coverage report using coverage.py_::

    make coverage

Visit Bitbucket_ if you'd like to fork the project, watch for new
changes, or report issues.

.. _Mercurial:
.. _Bitbucket:
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