Sphinx version 2 blocks xapian-bindings compilation

[karolyi]

Sphinx 2.x got released in Feb 27 2019. Since the xapian-bindings compilation for python uses a non-versioned Sphinx, the configure command fails because the sphinx module doesn't have a main() property anymore.

[Olly Betts]

You seem eager to get this fixed in the next release - providing a patch (ideally one which still leaves things working with older Sphinx too) is the best way to make that happen.

[karolyi]

Replying to olly:

You seem eager to get this fixed in the next release - providing a patch (ideally one which still leaves things working with older Sphinx too) is the best way to make that happen.

I can give it a try and create a PR on the github repo if that suffices. However, I'll only add the change for python3, since python 2.x is legacy anyways.

Is that okay with you?

[Olly Betts]

Our python 2.x support needs to keep working while we have it, but it looks like sphinx 2.0 doesn't support python 2.x anyway (​https://www.sphinx-doc.org/en/master/changes.html says "Drop python 2.7 and 3.4 support" for 2.0.0b1) so there's no reason to update it for changes in sphinx 2.0.

Hmm, I also don't see any mention of changes to sphinx.main() in 2.0 on ​https://www.sphinx-doc.org/en/master/extdev/deprecated.html#dev-deprecated-apis

[Olly Betts]

Fixed in git master in [7a8f1d479ec26b600eb05525140e4d648cf297c5]. Should be backported for 1.4.12.

[Arthur Pemberton]

I'm glad I found this. As of now, the Xapain installation process for Python 3 is basically broken.

Any fix?

[Arthur Pemberton]

What was the last working version of Sphinx?

[Arthur Pemberton]

Changing configure:17286 from if $PYTHON3 -c 'import sphinx;print(repr(sphinx.main))' >&5 2>&5 ; then to if $PYTHON3 -c 'from sphinx.cmd.build import main;print(repr(main))' >&5 2>&5 ; then may work.

[Arthur Pemberton]

In the mean time, for anyone finding this, changing pip install sphinx to pip install -U Sphinx==1.8.5 in install_xapian.sh allows one to complete the install.

[Olly Betts]

What was the last working version of Sphinx?

Whatever the last version before 2.0 was.

This should be fixed in git master, but hand-applying the fix to allow building the latest xapian release is probably not trivial - installing an older sphinx version is a simpler workaround.

There should be new release with a backport of this fix fairly soon.

[Olly Betts]

Follow-on fixes on master: [ba557b0ef09a11f2513a61a7825963dedf45b6f5] [2f51e4d8ddb0d757cf703d7fd412e33dcef765a1]

The CI on macOS is now building python3 and passing, and that uses Sphinx 2.0 from homebrew.

Backported to RELEASE/1.4: [dc07f43c51eb4a70b16245f70615d4326ea67ccc] [98cdd3ee78b417fe1f2dbd3089586ddd2e0fc25e] [14c1801ddeb38e26f3725272f97f0ead851b46e0]