Phoenix/docs/sphinx/rest_substitutions/overviews/DocstringsGuidelines.rst

.. include:: headings.inc

.. highlight:: rst


.. _docstrings guidelines:

==================================================
|phoenix_title|  **Phoenix Docstrings Guidelines**
==================================================

This document gives a brief introduction about the current docstrings standards
in the Phoenix project. Most of the documentation in the Phoenix core is automatically
generated by parsing the wxWidgets XML docs; however, Phoenix has its own pure-Python
functions and classes in at least two places:

* **Core Library**: examples include :ref:`CallLater` and :func:`date2pydate`, which require
  manual input of the documentation strings. This is achieved by editing the source Python files
  located in the ``etg`` folder in the Phoenix directory tree;
* **wx.lib**: the whole of ``wx.lib`` (and its sub-folders) is made up of pure-Python modules,
  often representing owner-drawn widgets which are not available as wrapped modules. Again,
  this requires manual editing of the source Python files.

This document is a starting point in setting some reasonable standards on how the pure-Python
docstrings may be edited and improved to make the overall appearance of the Phoenix documentation
consistent and pleasant.


.. _info field lists:

Info Field Lists
----------------

`Info Field Lists` refer to the various options available while documenting a method or a function,
and in particular its parameters, keywords, return type and possibly raised Python `Exceptions`.

Inside Python object description directives, reST field lists with these fields
are recognized and formatted nicely:

* ``param``, ``parameter``, ``arg``, ``argument``, ``key``, ``keyword``:
  Description of a parameter.
* ``type``: Type of a parameter.
* ``raises``, ``raise``, ``except``, ``exception``: That (and when) a specific
  exception is raised.
* ``var``, ``ivar``, ``cvar``: Description of a variable.
* ``returns``, ``return``: Description of the return value.
* ``rtype``: Return type.


The field names must consist of one of these keywords and an argument (except
for ``returns`` and ``rtype``, which do not need an argument). This is best
explained by an example::

    .. method:: Set3StateValue(self, state):

       Sets the checkbox item to the given `state`.

       :param `state`: can be one of: ``wx.CHK_UNCHECKED`` (check is off), ``wx.CHK_CHECKED``
        (check is on) or ``wx.CHK_UNDETERMINED`` (check is mixed).
       :type `state`: integer

       :returns: ``True`` if the value was successfully set, ``False`` otherwise.
       :rtype: bool

       :raise: `Exception` when the item is not a 3-state checkbox item.

|

This will render like this:

    .. method:: Set3StateValue(self, state):
       :noindex:

       Sets the checkbox item to the given `state`.

       :param `state`: can be one of: ``wx.CHK_UNCHECKED`` (check is off), ``wx.CHK_CHECKED``
        (check is on) or ``wx.CHK_UNDETERMINED`` (check is mixed).
       :type `state`: integer

       :returns: ``True`` if the value was successfully set, ``False`` otherwise.
       :rtype: bool

       :raise: `Exception` when the item is not a 3-state checkbox item.


|

It is also possible to combine parameter type and description, if the type is a
single word, like this::

   :param integer `state`: can be one of: ``wx.CHK_UNCHECKED`` (check is off), ``wx.CHK_CHECKED``
    (check is on) or ``wx.CHK_UNDETERMINED`` (check is mixed).


In general, the standards for the ``:param`` field are the following:

1. Do not use the ``@param`` construct, as I am not sure Sphinx and docutils understand it;
2. Always try and define the parameter type: if the parameter is another Phoenix class, you can simply
   write this::

       :param Point `pt`: the mouse pointer location.

   Or, alternatively::

       :param `pt`: the mouse pointer location.
       :type `pt`: Point


Similarly, for the ``:return:`` and ``:rtype:`` field, you may consider doing the following:

1. Try and put double-backticks on words like ``True``, ``False``, ``None`` and the various
   Phoenix constants (i.e., ``wx.TR_DEFAULT_STYLE``);
2. If you can't guess what a method function returns, just leave the ``:returns:`` and ``:rtype:``
   fields blank.


.. seealso:: `Sphinx Info Field List <http://sphinx.pocoo.org/domains.html#info-field-lists>`_


.. _admonitions:

Admonitions
-----------

Admonitions are specially marked "topics" that can appear anywhere an ordinary body element can.
They contain arbitrary body elements. Typically, an admonition is rendered as an offset block
in a document, sometimes outlined or shaded, with a title matching the admonition type. For example::

    .. warning:: I am a warning.


Will render as:

.. warning:: I am a warning.

|

Currently, the `sphinx_generator` tool recognizes the following admonitions:

1. ``.. note::`` or ``:note:`` : simple annotations to make a particular comment/sentence
   stand out against the rest of the documentation strings for a particular class, method or function;
2. ``.. warning::`` : this admonition normally indicates a problem or a severe limitation of a method,
   class or function. In the Phoenix world, this may also indicate that a particular widget is not
   supported under one or more platforms;
3. ``.. deprecated::`` : used to mark deprecated methods, classes or functions;
4. ``.. availability::`` : normally employed to make the user understand on which platform(s) a particular
   functionality is supported/available;
5. ``.. seealso::`` or ``:see:`` : added primarily to facilitate the browsing of the docs, this admonition
   should be employed every time you think a user may be interested in seeing a related/similar method
   or a function providing an alternative implementation;
6. ``.. todo::`` : used to mark incomplete methods/functions, or simply as a remainder for the user and
   the developer that some more functionality needs to be added.

You can put pretty much anything inside an admonition section, as long as it is properly indented. The
recommendation is to implement it like this::

    .. note::

       The class :ref:`TreeCtrl` can be used to display a tree, with these notes:

       - The note contains all indented body elements
         following.
       - It includes this bullet list.
       

|

Which will render as follows:

.. note::

   The class :ref:`TreeCtrl` can be used to display a tree, with these notes:

   - The note contains all indented body elements
     following.
   - It includes this bullet list.



In addition to the aforementioned admonitions, you can also use the default Sphinx directives
like ``.. versionadded::`` and ``.. versionchanged::``, to highlight the fact that some method, 
function or class has been added/modified starting with a particular Phoenix version.


.. seealso:: `Sphinx Paragraph-level markup <http://sphinx.pocoo.org/markup/para.html>`_


.. _contributing samples:

Contributing Samples
--------------------

.. highlight:: python

If you wish to contribute a (short) sample to be included in the documentation, please follow 
these conventions:

1. Name the snippet of code like ``classname.methodname.INTEGER.py``, i.e. if you wish to contribute 2
   snippets about the :meth:`CheckBox.SetValue` method, please name your snippet files like this:

   * `CheckBox.SetValue.1.py`
   * `CheckBox.SetValue.2.py`
   
   
2. At the very top of the snippet file (on the first line), put your name, or your alias, or anything
   you use as internet name preceeded by a double-hash, i.e.:
   
   ``##Andrea Gavana``
   
   
   So that your source code looks more or less like this::
   
       ##Chris Barker
       #!/usr/bin/env python

       """
       A simple test of the GridBagSizer
       http://wiki.wxpython.org/index.cgi/WriteItYourself
       """
   
       # Whatever code here...
       def SendSizeEvent(self):
       
           self.AdjustMySize()



.. highlight:: rst

This snippet will end up in the snippets `contrib` folder, to differentiate it from the snippets 
automatically generated when parsing the wxWidgets C++ XML documentation.

Please keep the snippets as short as possible: they don't need to be fully-runnable and self contained
applications, they are simply meant to show a particular/clever/unusual way of using a method, a class
or a function.

Please do send your sample snippets to me at `this <andrea.gavana@gmail.com>`_ e-mail address or, if
you have commit rights in the current Phoenix SVN area, feel free to upload them yourself under the
following folder:

``/trunk/docs/sphinx/rest_substitutions/snippets/python/contrib``


.. _contributing screenshots:

Contributing Screenshots
------------------------

Currently Phoenix is relatively short of widgets screenshots, especially on Linux/Mac platforms.

If you wish to contribute a screenshot of a widget to be included in the documentation, please follow 
these conventions:

- If the widget is a class belonging to the main `wx` namespace, just use the
  class name in lower case (i.e., `wx.Frame` ==> `frame.png`);
- If it belongs to a sub-namespace (i.e., `wx.dataview`, `wx.aui`, `wx.html`
  and so on), it should be named this way (examples):

  1) `wx.dataview.DataViewCtrl` ==> `dataview.dataviewctrl.png`
  2) `wx.aui.AuiManager` ==> `aui.auimanager.png`


Please do send your screenshots to me at `this <andrea.gavana@gmail.com>`_ e-mail address or, if
you have commit rights in the current Phoenix SVN area, feel free to upload them yourself under the
following folder:

``/trunk/docs/sphinx/_static/images/widgets/fullsize``

Please make sure to upload your images in the appropriate sub-folder, depending on the platform you
chose to take the screenshots on.