====
Doc8
====

Doc8 is a *opinionated* style checker for `rst`_ (with basic support for
plain text) styles of documentation.

QuickStart
==========

::

    pip install doc8

To run doc8 just invoke it against any doc directory::

    $ doc8 coolproject/docs

Usage
=====

Command line usage
******************

::

    $ doc8  -h

    usage: doc8 [-h] [--config path] [--allow-long-titles] [--ignore code]
                [--no-sphinx] [--ignore-path path] [--ignore-path-errors path]
                [--default-extension extension] [--file-encoding encoding]
                [--max-line-length int] [-e extension] [-v] [--version]
                [path [path ...]]

    Check documentation for simple style requirements.

    What is checked:
        - invalid rst format - D000
        - lines should not be longer than 79 characters - D001
          - RST exception: line with no whitespace except in the beginning
          - RST exception: lines with http or https urls
          - RST exception: literal blocks
          - RST exception: rst target directives
        - no trailing whitespace - D002
        - no tabulation for indentation - D003
        - no carriage returns (use unix newlines) - D004
        - no newline at end of file - D005

    positional arguments:
      path                  Path to scan for doc files (default: current
                            directory).

    optional arguments:
      -h, --help            show this help message and exit
      --config path         user config file location (default: doc8.ini, tox.ini,
                            pep8.ini, setup.cfg).
      --allow-long-titles   allow long section titles (default: false).
      --ignore code         ignore the given error code(s).
      --no-sphinx           do not ignore sphinx specific false positives.
      --ignore-path path    ignore the given directory or file (globs are
                            supported).
      --ignore-path-errors path
                            ignore the given specific errors in the provided file.
      --default-extension extension
                            default file extension to use when a file is found
                            without a file extension.
      --file-encoding encoding
                            override encoding to use when attempting to determine
                            an input files text encoding (providing this avoids
                            using `chardet` to automatically detect encoding/s)
      --max-line-length int
                            maximum allowed line length (default: 79).
      -e extension, --extension extension
                            check file extensions of the given type (default:
                            .rst, .txt).
      -v, --verbose         run in verbose mode.
      --version             show the version and exit.

Ini file usage
**************

Instead of using the CLI for options the following files will also be examined
for ``[doc8]`` sections that can also provided the same set of options. If
the ``--config path`` option is used these files will **not** be scanned for
the current working directory and that configuration path will be used
instead.

* ``$CWD/doc8.ini``
* ``$CWD/tox.ini``
* ``$CWD/pep8.ini``
* ``$CWD/setup.cfg``

An example section that can be placed into one of these files::

    [doc8]

    ignore-path=/tmp/stuff,/tmp/other_stuff
    max-line-length=99
    verbose=1
    ignore-path-errors=/tmp/other_thing.rst;D001;D002

**Note:** The option names are the same as the command line ones (with the
only variation of this being the ``no-sphinx`` option which from
configuration file will be ``sphinx`` instead).

Option conflict resolution
**************************

When the same option is passed on the command line and also via configuration
files the following strategies are applied to resolve these types
of conflicts.

=====================  ===========  ========
Option                 Overrides    Merges
=====================  ===========  ========
``allow-long-titles``  Yes          No
``ignore-path-errors`` No           Yes
``default-extension``  Yes          No
``extension``          No           Yes
``ignore-path``        No           Yes
``ignore``             No           Yes
``max-line-length``    Yes          No
``file-encoding``      Yes          No
``sphinx``             Yes          No
=====================  ===========  ========

**Note:** In the above table the configuration file option when specified as
*overrides* will replace the same option given via the command line. When
*merges* is stated then the option will be combined with the command line
option (for example by becoming a larger list or set of values that contains
the values passed on the command line *and* the values passed via
configuration).

.. _rst: http://docutils.sourceforge.net/docs/ref/rst/introduction.html