elpa version 20191101.1756 is somehow partly broken for a Python 3-based sage

[EmmanuelCharpentier]

Seen after this morning's upgrade of my elpa packages, which installed sage-shell-mode-20191101.1756 :

• when $SAGE_ROOT points to a Python 3-based Sage installation, sage-shell-mode displays the Sage banner, and never gets the prompt, thus becoming unusable. I had to kill emacs...

• when $SAGE_ROOT points to a Python 2-based Sage installation, sage-shell-mode works as expected (displays 2D graphs and typesets expressions in the *Sage* buffer when the relevant toggles are set).

• However, when I repeat the first operation (after switching a symlink to change back SAGE_ROOT to Python 3-based Sage), sage-shell-mode:

  • starts normally
  • can display 2d plots in the *Sage* buffer,
  • but won't typeset expressions, as already reported in issue #45.

The first instance of the problem may be a post-install glitch.And #45 still stands, becoming an urgent issue with Sage 9.0 (Python 3-based by default) looming over the horizon...

HTH,