[singlehtml] toctree no filename with anchor

[gastmaier]

Purpose

Fix toctree links to page anchor in the singlehtml output.
Only matters for themes that include the right sidebar in the singlehtml page, but particularly useful for using the singlehtml to then generate a pdf (since the toctree allows fine tuning the depth of the table of contents).

On #11970, same-document links dropped the uri (filename part). On #12551, fixes to do not include the filename on hyperlinks was added. So an anchor for a:

• doc reference: #document-my-page
• ref reference: #my-anchor.

On #13037, fix_refuris was removed, which would blindly rmatch #.*
However, #12551 missed the toctree constructor, which was still generating:

• #document-my-page#my-anchor

Modify _resolve_toctree() to do not include rel_uri if the is an anchorname.

Tests failing

These two tests are failing, from the immediate previous commit:

FAILED tests/test_builders/test_build_epub.py::test_nested_toc - AssertionError: assert ('navPoint5',...o-1', 'foo.1') == ('navPoint5',...o-1', 'foo.1')
FAILED tests/test_builders/test_build_epub.py::test_escaped_toc - AssertionError: assert ('navPoint5',...1', 'foo “1”') == ('navPoint5',...1', 'foo “1”')

It may be necessary to make the code specific to when the builder is singlehtml.

References

• 🐛 Fix singlehtml target uris to be same-document references #11970,
• singlehtml: Use same-document hyperlinks for internal project references #12551
• singlehtml: deprecate the 'fix_refuris' helper function #13037

[gastmaier]

Changed the approach to only affect singlehtml.
since the original approach would break toctrees that include anchor and are multi file (e.g. html):

toctree_html = context["toctree"](
    collapse=False,
    titles_only=False,
    maxdepth=-1,
    includehidden=True,
)

It may be worth considering that after all, having the filename in the anchor #document-<filename>, may be more consistent with other single file builders (epub, ...?)

pinging @jayaddison for insight