Add missing use_develop to tox.ini

[mtreinish]

Summary

In #11119 we removed the use_develop flag in the tox config which was used to tell tox to use a single editable install for running a job (avoiding the need to build from sdist on every run) as part of a temporary refactoring to ensure we installed the metapackage along with terra. Now that we've standardized the packaging in #11271 that was undone, but the usedevelop flag was not added back. This has caused tox to rebuild the package from sdist on every run even if there are no code changes. This commit restores the missing option to fix this.

Details and comments

[qiskit-bot]

One or more of the the following people are requested to review this:

• @Qiskit/terra-core

[coveralls]

Pull Request Test Coverage Report for Build 9172475719

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 13 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.01%) to 89.601%

---

Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/parse.rs	6	97.15%
crates/qasm2/src/lex.rs	7	92.37%

Totals
Change from base Build 9163549280:	-0.01%
Covered Lines:	62294
Relevant Lines:	69524

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💛 - Coveralls

[jakelishman]

tbf, I think this is tox doing what it's intended to do. If you want to skip the reinstall step with tox 4, the command is

tox run --skip-pkg-install [-e py310]

That said, I don't really use the testenv environments from tox, so I'm also fine if you'd rather switch it back to using the editable installs.

[wshanks]

A problem developers run into is that that without use_develop the qiskit in the repo takes precedence over the version installed by tox and then fails to import if the Rust components have not been compiled in the repo. Somehow that should be fixed.

One option is to set use_develop. Another would be to add PYTHONSAFEPATH=1 to tox's setenv. The first option would be faster since it would not need to rebuild the Rust libraries on every run. The second one would be more correct since it would be testing installation from a wheel and could catch packaging issues. There could be some middle ground between the two by setting tox up to build the package in the repo or other fixed directory instead of in a temporary directory so that it can reuse the Rust libraries when building the wheel.

[mtreinish]

The reason I didn't go for PYTHONSAFEPATH is that it's not supported on older versions of Python, it only works with Python >=3.11 but we still support older python versions. The way I solved this in rustworkx was to set changedir = {toxinidir}/tests so that all the tox commands run out of tests/ instead of the repo root which would also work. I don't have a strong opinion, but this issue has been a pain for too long on local development so picking a solution and implementing it would be good.

[wshanks]

Ah, okay. I also don't have a preference but agree something should be done. I use my own environment for the most part and only use tox if something I run seems odd and I want retry it in a clean environment.