Missing pygments Styles on RTD Hosted Docs

[shawnbrown]

Problem

Since the first week of May 2018 (coinciding with the release sphinx_rtd_theme 0.3.1), some projects on http://readthedocs.org no longer display syntax highlighting. While the live site no longer highlights code, the HTML and PDF downloads seem to be fine.

The HTML files do include the proper Pygments class attributes...

<div class="code python highlight-default">
    <div class="highlight">
        <pre>
            <span></span><span class="n">html_theme</span> <span class="o">=</span> <span class="s2">&quot;sphinx_rtd_theme&quot;</span>
            <span class="n">html_theme_path</span> <span class="o">=</span> <span class="p">[</span><span class="s2">&quot;_themes&quot;</span><span class="p">,</span> <span class="p">]</span>
        </pre>
    </div>
</div>

...but builds on http://readthedocs.org no longer include any CSS styles for these classes.

These styles used to be included in theme.css but they were removed: c43d473#diff-8b5d5b0b20fffbc206fe1081243fb125L4. Locally, my builds include pygments.css but this file is not being included on the live site.

Reproducible Project

I first noticed this with my own docs but I see that this is also happening in the sphinx-rtd-theme docs too:

• http://datatest.readthedocs.io/en/stable/tutorial/querying-data.html#loading-data
• https://sphinx-rtd-theme.readthedocs.io/en/latest/installing.html#via-git-or-download

Error Logs/Results

My builds are passing so I don't think this has anything to do with a change in my own conf.py:

• https://readthedocs.org/projects/datatest/builds/

Environment Info

Since this occurs on http://readthedocs.org/, I don't have access to the environment details but it does appear to be using sphinx-rtd-theme 0.3.1.

[Blendify]

@agjohnson seems like an error on RTD.

[stsewd]

Maybe is the same issue as readthedocs/readthedocs.org#4050?

[jessetan]

Your latest docs do have syntax highlighting, but your stable does not. This looks like it was fixed by pinning to a newer version of the theme.

[shawnbrown]

@jessetan, yes I pinned the new version (as mentioned in the link @stsewd provided) and changed my pygments_style property.

Here are the specific changes I made:

• In the documentation's conf.py file, I changed pygments_style = 'sphinx' to pygments_style = 'default'.
• In the project's requirements.txt, I changed sphinx_rtd_theme to sphinx_rtd_theme>=0.3.1.

This seems to have worked for me. I'll leave closing this issue up to your discretion--I wouldn't have opened a new issue, myself, if I had seen the closed one in the readthedocs.org repo so maybe it's good to keep this open until the updated theme is used by default on Read the Docs.

[davidfischer]

I'll wait until readthedocs/readthedocs.org#4096 rolls out and then I think we can close this.

[ericholscher]

This should be fixed 👍