Remove bad mathjax symlink and bad mathjax directories

[jhpalmieri]

The problem reported in #26152 has returned, it seems. As a result, users may end up with a symlink SAGE_SHARE/mathjax/mathjax pointing to its parent directory, and this ends up producing a directory SAGE_DOC/html/en/reference/_static/mathjax which contains a subdirectory mathjax which also contains a subdirectory mathjax, etc., hence needlessly using gigabytes of disk space. Let's get rid of these problematic files.

Depends on #26641

Component: documentation

Author: John Palmieri

Branch/Commit: u/jhpalmieri/no-mathjax @ ae3812d

Issue created by migration from https://trac.sagemath.org/ticket/26612

[jhpalmieri]

Branch: u/jhpalmieri/no-mathjax

[jhpalmieri]

New commits:

ae3812d

trac 26612: remove bad mathjax symlink and any resulting bad mathjax directories.

[jhpalmieri]

Commit: ae3812d

[jhpalmieri]

comment:3

I still don't know what causes the symlink to be created, but let's delete it when we build the documentation.

[jdemeyer]

comment:4

I don't like this kind of code. We really should fix the underlying problem instead. Do you have a way to reproduce it?

[jhpalmieri]

comment:5

I don't have a way to reproduce it. There are two issues, in my mind: first, yes, we want to fix the underlying issue, but that seems hard since we don't know what the issue is. Second, there may be people out there who are suffering from this problem and don't realize it and so are wasting huge amounts of disk space. Shouldn't we clean up that mess?

[jhpalmieri]

comment:6

I have one computer on which I can recreate the self-referential symlink by running ./sage -f sagenb. I think the problem comes from this: sagenb is distributed with a full copy of mathjax in its data directory. The installation procedure is supposed to replace this copy with a symlink, and something goes wrong. Why is sagenb distributed with a copy of mathjax in the first place, since mathjax has been a separate Sage package for a while? Now I'm tempted to do this:

diff --git a/build/pkgs/sagenb/spkg-install b/build/pkgs/sagenb/spkg-install
index 57864ab0d9..639de1d23d 100644
--- a/build/pkgs/sagenb/spkg-install
+++ b/build/pkgs/sagenb/spkg-install
@@ -17,5 +17,6 @@ fi
 PYTHON_VERSION=$("$SAGE_LOCAL/bin/$PYTHON" -c 'import sys; print("%d.%d" % sys.version_info[:2])')
 cd "${SAGE_DESTDIR}${SAGE_LOCAL}/lib/python$PYTHON_VERSION/site-packages/sagenb/data" || \
     sdh_die "Cannot find SageNB data directory."
+rm -rf mathjax
 ln -s -n "$SAGE_SHARE/mathjax/" mathjax || \
     sdh_die "Error: Cannot symlink mathjax into the SageNB data directory."

along with a command at the start of sagenb's installation to remove the directory sagenb/data/mathjax, if it is not a symlink. Or maybe unconditionally.

Or something along these lines.

[jhpalmieri]

comment:7

This doesn't explain things completely, of course: why can I reliably reproduce this on one computer and not another? On the computer where I can reproduce it, I first installed an older version of sagenb, removed the bad symlink, and then did an incremental update to the current develop branch. What remnants from the old build could be causing the symlink to get reproduced each time I do ./sage -f sagenb?