sage.features.Executable: Prepend $SAGE_VENV/bin:$SAGE_LOCAL/bin to PATH

[mkoeppe]

Follow-up from #22731.

This is so that Sage becomes fully functional even when not being run from within sage-env (which sets PATH)

Of course, PATH is not actually manipulated, only Executable finds the executable in more places.

As an illustration, we update sage.interfaces.four_ti_2 and sage.interfaces.latte to use Executable.absolute_filename() from #31292. Then, after sage -i 4ti2 latte_int, the following works with this ticket:

$ venv/bin/python3 -c 'import sage.all; from sage.interfaces.four_ti_2 import four_ti_2; print(four_ti_2.groebner(lat=[[1,2,3],[1,1,1]]))'
$ venv/bin/python3 -c 'from sage.all import *; print(Polyhedron([[-3, 0], [0, 9]]).volume(measure="induced_rational"))'
3

In follow-up tickets, other code that calls executables needs to be updated to use Executable.absolute_path() from #31292. The first tickets to do so are #33440, #33465, #33466, #32645, #33467, #33405.

This is work towards:

• Meta-ticket: Set environment for subprocesses invoked by Sage #30818 Meta-ticket: Set environment for subprocesses invoked by Sage
• Meta-ticket: Replace imports from deprecated distutils #31295 Meta-ticket: Replace imports from deprecated distutils

Depends on #31292

CC: @tobiasdiez @kiwifb @tobihan @antonio-rojas @orlitzky

Component: build: configure

Author: Matthias Koeppe

Branch/Commit: 160e9af

Reviewer: Dima Pasechnik, Tobias Diez

Issue created by migration from https://trac.sagemath.org/ticket/31296

[mkoeppe]

Description changed:

--- 
+++ 
@@ -1,4 +1,6 @@
 Follow-up from #22731.
+
+This is so that Sage becomes fully functional even when not being run from within `sage-env` (which sets `PATH`)
 
 This is work towards:
 - #30818 Meta-ticket: Set environment for subprocesses invoked by Sage

[mkoeppe]

comment:2

Sage development has entered the release candidate phase for 9.3. Setting a new milestone for this ticket based on a cursory review of ticket status, priority, and last modification date.

[mkoeppe]

Dependencies: #32565

[mkoeppe]

Changed dependencies from #32565 to none

[mkoeppe]

Dependencies: #31292

[mkoeppe]

Branch: u/mkoeppe/sage_features_executable_SAGE_LOCAL

[mkoeppe]

Author: Matthias Koeppe

[mkoeppe]

New commits:

32ce831	sage.features.Executable.absolute_path: New
88860d3	sage.features.Executable.absolute_path: If SAGE_LOCAL != SAGE_VENV, search first in SAGE_VENV/bin, SAGE_LOCAL/bin, then PATH

[mkoeppe]

Commit: 88860d3

[sagetrac-git]

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

8801359

src/sage/features/__init__.py: Fix import

[sagetrac-git]

Changed commit from 88860d3 to 8801359

[sagetrac-git]

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

403bcc1

sage.features.Executable: Fix up

[sagetrac-git]

Changed commit from 8801359 to 403bcc1

[mkoeppe]

Description changed:

--- 
+++ 
@@ -1,6 +1,10 @@
 Follow-up from #22731.
 
 This is so that Sage becomes fully functional even when not being run from within `sage-env` (which sets `PATH`)
+
+Of course, `PATH` is not actually manipulated, only `Executable` finds the executable in more places.
+
+In follow-up tickets, code that calls executables needs to be updated to use `Executable.absolute_path()` from #31292. The first ticket to do so is #33440.
 
 This is work towards:
 - #30818 Meta-ticket: Set environment for subprocesses invoked by Sage

[sagetrac-git]

Changed commit from 403bcc1 to 9fad95e