Sagelib's scripts in src/bin should not use build/bin/sage-system-python; remove sage-pypkg-location

[mkoeppe]

In previous tickets we have moved sage-the-distribution scripts out of src/bin.

Some scripts that are (correctly) located in src/bin use sage-system-python, which is in build/bin and not installed and not available in distributions.

src/bin/sage-coverage:1:#!/usr/bin/env sage-system-python
src/bin/sage-pypkg-location:1:#!/usr/bin/env sage-system-python
src/bin/sage-coverageall:1:#!/usr/bin/env sage-system-python
src/bin/sage-num-threads.py:1:#!/usr/bin/env sage-system-python

We change sage-coverage* to just use python3. If Sage's venv is in the front of the PATH, this is Sage's python. But these scripts work with "any python3", it does not have to be the one in which sage is installed.

We remove src/bin/sage-pypkg-location, which is undocumented and unused.

We move src/bin/sage-num-threads.py to build/bin/sage-build-num-threads (where it keeps using sage-system-python), leaving a much simplified version src/bin/sage-num-threads.py (which is using python3) behind.

[mkoeppe]

#29951 will only put $SAGE_ROOT/bin in $PATH if $SAGE_ROOT is set and readable.

Repurposing this ticket to change scripts in src/bin to not use sage-system-python (which is in build/bin and not installed and not available in distributions).

[mkoeppe]

New commits:

​063a0af	src/bin/sage-pypkg-location: Remove
​f6dcc14	src/bin/sage*: Do not use sage-system-python

[jhpalmieri]

sage-num-threads.py gets used in the build process, I think: it gets used in src/bin/sage-env. So I think this change will break building on systems with no Python 3 anywhere. Do we need to support such systems?

[mkoeppe]

Thanks for catching this. This needs some thought

[jhpalmieri]

I think the issue is that the line between build scripts and runtime scripts is blurred. sage-env and sage-num-threads.py, maybe others?

[mkoeppe]

Yes, I agree, I think the solution is to split the build-specific parts (parsing MAKEFLAGS) out from sage-num-threads.py. I'll work on it.

[jhpalmieri]

Sounds good to me.

[git]

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

​f76082a	Merge tag '9.2.beta13' into t/29355/sagelib_s_scripts_in_src_bin_should_not_use_build_bin_sage_system_python__remove_sage_pypkg_location
​ab72437	build/bin/sage-build-num-threads: Copy from src/bin/sage-num-threads.py, simplify src/bin/sage-num-threads.py
​1e797a1	build/make/install: Set SAGE_NUM_THREADS, SAGE_NUM_THREADS_PARALLEL using sage-build-num-threads
​850f97c	src/bin/sage-env: If SAGE_NUM_THREADS, SAGE_NUM_THREADS_PARALLEL are set already, do not call sage-num-threads.py to set them

[mkoeppe]

In a follow-up ticket, we could probably get rid of src/bin/sage-num-threads.py completely by implementing the desired defaulting behavior in src/sage/parallel/ncpus.py and src/sage/doctest/control.py.

[mkoeppe]

Replying to mkoeppe:

In a follow-up ticket, we could probably get rid of src/bin/sage-num-threads.py completely by implementing the desired defaulting behavior in src/sage/parallel/ncpus.py and src/sage/doctest/control.py.

I have opened #30639 for that.

[mjo]

I should probably know the answer to this, but is there a promise that "python3" is the official name for the python interpreter in the future? After 2.x is completely dead, they're not going to change it back to "python"?

(This is also relevant when we're searching for (only) a system "python3")

[mjo]

The name "python3" should be OK for a long time:

• ​https://www.python.org/dev/peps/pep-0394/
• ​https://lwn.net/Articles/780737/

[mkoeppe]

and ​https://twitter.com/gvanrossum/status/1306082472443084801

[git]

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

​ef1444a

Merge tag '9.2.beta14' into t/29355/sagelib_s_scripts_in_src_bin_should_not_use_build_bin_sage_system_python__remove_sage_pypkg_location

[mkoeppe]

Needs review

[git]

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

​f4a75a9

Merge tag '9.3.beta0' into t/29355/sagelib_s_scripts_in_src_bin_should_not_use_build_bin_sage_system_python__remove_sage_pypkg_location

[git]

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

​a4e757e

build/pkgs/sagelib/src/setup.py: Remove bin/sage-pypkg-location

[mkoeppe]

Can we please get this ticket in?

[dimpase]

lgtm

[mkoeppe]

Thanks!

[slabbe]

I was currently checking it also. So, I confirm that sage -coverage and sage -coverageall still work. Also, sage-num-threads.py still seems to work:

(sage-sh) $ echo $SAGE_NUM_THREADS
1
(sage-sh) $ echo $SAGE_NUM_THREADS_PARALLEL
8

or the above were defined from build/make/install?

Anyway, I have:

sage: import os                                                                 
sage: os.environ['SAGE_NUM_THREADS']                                            
'1'
sage: os.environ['SAGE_NUM_THREADS_PARALLEL']                                   
'8'

positive review!

[mkoeppe]

Looks like this ticket was merged as part of #30627.