sphinx-js 1.2

Support for using Sphinx on JSDoc-documented JS code

Why

When you write a JavaScript library, how do you explain it to people? If it’s a small project in a domain your users are familiar with, JSDoc’s hierarchal list of routines might suffice. But what about for larger projects? How can you intersperse prose with your API docs without having to copy and paste things?

sphinx-js lets you use the industry-leading Sphinx documentation tool with JS projects. It provides a handful of directives, patterned after the Python-centric autodoc ones, for pulling JSDoc-formatted function and class documentation into reStructuredText pages. And, because you can keep using JSDoc in your code, you remain compatible with the rest of your JS tooling, like Google’s Closure Compiler.

Setup

1. Install JSDoc using npm. jsdoc must be on your $PATH, so you might want to npm install -g jsdoc. We’re known to work with jsdoc 3.4.3.

2. Install Sphinx. (TODO: Make this more explicit for non-Python people.)

3. Make a documentation folder in your project using sphinx-quickstart.

4. Add sphinx_js to extensions in the generated Sphinx conf.py.

5. Add js_source_path = '../somewhere/else' to conf.py, assuming the root of your JS source tree is at that path, relative to conf.py itself. The default is ../, which works well when there is a docs folder at the root of your project.

Use

In short, use the directives below, then build your Sphinx docs as usual by running make html in your docs directory.

autofunction

Document your JS code using standard JSDoc formatting:

/**
 * Return the ratio of the inline text length of the links in an element to
 * the inline text length of the entire element.
 *
 * @param {Node} node - Types or not: either works.
 * @throws {PartyError|Hearty} Multiple types work fine.
 * @returns {Number} Types and descriptions are both supported.
 */
function linkDensity(node) {
    const length = node.flavors.get('paragraphish').inlineLength;
    const lengthWithoutLinks = inlineTextLength(node.element,
                                                element => element.tagName !== 'A');
    return (length - lengthWithoutLinks) / length;
}

Our directives work much like Sphinx’s standard autodoc ones. You can specify just a function:

.. js:autofunction:: someFunction

Or you can throw in your own explicit parameter list, if you want to note optional parameters:

.. js:autofunction:: someFunction(foo, bar[, baz])

You can even add additional content. If you do, it will appear just below any extracted documentation:

.. js:autofunction:: someFunction

    Here are some things that will appear...

    * Below
    * The
    * Extracted
    * Docs

    Enjoy!

Use JSDoc namepath syntax to disambiguate same-named entities:

.. js:autofunction:: SomeClass#someInstanceMethod

Behind the scenes, sphinx-js will changes those to dotted names so that…

• Sphinx’s “shortening” syntax works: :func:`~InwardRhs.atMost` prints as merely atMost(). (For now, you should always use dots rather than other namepath separators: #~.)

• Sphinx indexes more informatively, saying methods belong to their classes.

To save some keystrokes, you can set primary_domain = 'js' in conf.py and then say simply autofunction rather than js:autofunction.

js:autofunction has one option, :short-name:, which comes in handy for chained APIs whose implementation details you want to keep out of sight. When you use it on a class method, the containing class won’t be mentioned in the docs, the function will appear under its short name in indices, and cross references must use the short name as well (:func:`someFunction`):

.. js:autofunction:: someClass#someFunction
   :short-name:

autoclass

We provide a basic js:autoclass directive which pulls in class comments and constructor docstrings, concatenating them. It’s otherwise identical to js:autofunction and even takes the same :short-name: flag, which can come in handy for inner classes. It doesn’t yet autodocument class members, but you can pull them in one at a time by embedding js:autofunction.

.. js:autoclass:: SomeEs6Class(args, if, you[, wish])

   .. js:autofunction:: SomeEs6Class#someMethod

   Additional content can go here and appears below the in-code comments.

Example

A good example using most of sphinx-js’s functionality is the Fathom documentation. A particularly juicy page is https://mozilla.github.io/fathom/ruleset.html. Click the “View page source” link to see the raw directives.

Caveats

• We don’t understand the inline JSDoc constructs like {@link foo}; you have to use Sphinx-style equivalents for now, like :js:func:`foo` (or simply :func:`foo` if you have set primary_domain = 'js' in conf.py.

• So far, we understand and convert only the JSDoc block tags @param, @returns, @throws, and their synonyms. Other ones will go poof into the ether.

Tests

Run python setup.py test.

Version History

1.2

• Always do full rebuilds; don’t leave pages stale when JS code has changed but the RSTs have not.

• Make Python-3-compatible.

• Add basic autoclass directive.

1.1

• Add :short-name: option.

1.0

• Initial release, with just js:autofunction