src/bin/sage-env: Make sure $SAGE_VENV/bin is at the beginning of the PATH

[mkoeppe]

Follow-up from #25486 (Discover SAGE_SCRIPTS_DIR to make $SAGE_LOCAL/bin/sage work from any directory, in an environment without SAGE_* variables) and #22731.

We make sure that $SAGE_VENV/bin (from #22731) appears at the beginning of the PATH. For virtual environments such as those set up by tox (#29950), this may be different from and should take precedence over $SAGE_LOCAL/bin. This will ensure that

• the correct copy of auxiliary scripts such as sage-eval is invoked by sage;
• the correct copy of python3 is run.

To determine SAGE_VENV:

• If src/bin/sage is invoked directly out of the source tree, it will run a new non-installed configure-generated script sage-src-env-config
• An installed sage script installed by setup.py in SAGE_LOCAL or in a venv will run a Python script sage-venv-config instead.

Depends on #29852

CC: @orlitzky @jhpalmieri

Component: scripts

Keywords: sd111

Author: Matthias Koeppe

Branch: 0140f84

Reviewer: Tobias Diez, Dima Pasechnik

Issue created by migration from https://trac.sagemath.org/ticket/30013

[mkoeppe]

Dependencies: #25486

[mkoeppe]

Changed dependencies from #25486 to #25486, #29951

[mkoeppe]

Changed dependencies from #25486, #29951 to #29951, #22731

[mkoeppe]

Changed dependencies from #29951, #22731 to #29951, #22731, #30888

[mkoeppe]

Changed dependencies from #29951, #22731, #30888 to #29951, #22731, #29852

[mkoeppe]

Branch: u/mkoeppe/src_bin_sage_env__make_sure__sage_venv_bin_is_at_the_beginning_of_the_path

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

842995f

src/bin/sage-venv-config: Add comment

[sagetrac-git]

Commit: 842995f

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

1a518c0

src/bin/sage: Set SAGE_VENV from sage-venv-config

[sagetrac-git]

Changed commit from 842995f to 1a518c0

[sagetrac-git]

Changed commit from 1a518c0 to d372ecf

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

d372ecf

src/bin/sage-env: Put $SAGE_VENV/bin before $SAGE_LOCAL/bin in PATH

[sagetrac-git]

Changed commit from d372ecf to 0140f84

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

0140f84

src/bin/sage-src-env-config.in: New, sourced in src/bin/sage

[mkoeppe]

Author: Matthias Koeppe

[mkoeppe]

comment:15

Using the new script sage-venv-config is probably overkill.
If #30888 resolves the symlink of $0, we could just infer the SAGE_VENV from its directory.

[tobiasdiez]

comment:17

Replying to @mkoeppe:

Using the new script sage-venv-config is probably overkill.
If #30888 resolves the symlink of $0, we could just infer the SAGE_VENV from its directory.

Why do you actually need go through the trouble of determining SAGE_VENV in some shell scripts? Isn't it enough to use SAGE_VENV = sys.prefix (which is already done in env.py)?

[mkoeppe]

comment:18

Replying to @tobiasdiez:

Replying to @mkoeppe:

Using the new script sage-venv-config is probably overkill.
If #30888 resolves the symlink of $0, we could just infer the SAGE_VENV from its directory.

Why do you actually need go through the trouble of determining SAGE_VENV in some shell scripts? Isn't it enough to use SAGE_VENV = sys.prefix (which is already done in env.py)?

Yes, for all Python scripts, sys.prefix does the right thing. But sage is a shell script (changing that would be outside of the scope of this ticket) and so we have to go through some extra trouble to determine this value in order to set PATH correctly.

[dimpase]

Reviewer: Tobias Diez, Dima Pasechnik

[dimpase]

comment:19

lgtm

[mkoeppe]

comment:20

Thanks!

[mkoeppe]

Changed dependencies from #29951, #22731, #29852 to #29852

[mkoeppe]

Changed keywords from none to sd111

[vbraun]

Changed branch from u/mkoeppe/src_bin_sage_env__make_sure__sage_venv_bin_is_at_the_beginning_of_the_path to 0140f84

[antonio-rojas]

Changed commit from 0140f84 to none

[antonio-rojas]

comment:24

This breaks if sage_conf is not installed, because VERSION is defined there

Traceback (most recent call last):
  File "/usr/bin/sage-venv-config", line 29, in <module>
    _main()
  File "/usr/bin/sage-venv-config", line 17, in _main
    version='%(prog)s ' + VERSION)
NameError: name 'VERSION' is not defined

If this is really intended and sage_conf is now mandatory, then ImportError from sage_conf shouldn't be trapped. But I hope it can still be possible to support sage_conf-less systems.

[mkoeppe]

comment:25

sage_conf is still intended to be optional - this is a regression, patches welcome

[antonio-rojas]

comment:26

OK, glad to hear - so what should we do if there's no sage_conf? don't add the --versionargument? get the version from somewhere else (where)?

[mkoeppe]

comment:27

I have created #31058 for this