gh-139588: Docs: PDF: convert SVG to PDF using sphinxcontrib.rsvgconverter

[m-aciek]

#133591 introduced an SVG into docs, which is not handled by LaTeX (used for PDF build) natively. This fixes the PDF build error. Uses a recommended approach.

(Better) alternative to #139635.

Render:

• Issue: make dist-pdf is broken #139588

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📚 Documentation preview 📚: https://cpython-previews--140342.org.readthedocs.build/

[hugovk]

This will install and use the extension for all builds, including HTML and others not building PDFs. Is that intentional?

[m-aciek]

This will install and use the extension for all builds, including HTML and others not building PDFs. Is that intentional?

The extension is quite lightweight itself, 28.95 KB [1], and skips converting for builders other that LaTeX. I think that it's not worth to introduce handling of optional dependencies for docs builds because of it.

[1]

% uvx --from pypkgsize pkgsize analyze --path Doc/venv --name sphinxcontrib-svg2pdfconverter
Inspecting packages in virtual environment: /Users/m-aciek/projects/cpython/Doc/venv...
Successfully retrieved package data from /Users/maciej.olko/projects/cpython/Doc/venv.
Package Name                   | Version         | Size         | Location
--------------------------------------------------------------------------
sphinxcontrib-svg2pdfconverter | 1.3.0           | 28.95 KB     | /Users/m-aciek/projects/cpython/Doc/venv/lib/python3.13/site-packages

[AA-Turner]

I'm also unsure about using another third-party extension. Could we not just use the latex customisation features to include the required LaTeX packages?

A

[m-aciek]

Could we not just use the latex customisation features to include the required LaTeX packages?

We can include svg package, but replacing \sphinxincludegraphics with \includesvg is more problematic. It would probably require a custom extension? So maybe it would be worth to bring it upstream instead? I don't feel familiar with Sphinx enough and both of those ways seem more problematic then the solution in this PR.

[AA-Turner]

the solution in this PR

involves bringing in a third-party dependency, who's code we haven't audited, etc. I will point out that until recently, no one had noticed the problem with this particular SVG file, which was added some months ago!

A

[AA-Turner]

For the avoidance of doubt I'll close this PR, it isn't the right solution.

A

[m-aciek]

I will point out that until recently, no one had noticed the problem with this particular SVG file, which was added some months ago!

For what it's worth, in PL translation project we build PDFs for stable branches only, the SVG/PDF issue impacts main branch only.