Why publish.yml flip between sh and bash?

[pllim]

https://github.com/OpenAstronomy/github-actions-workflows/blob/main/.github/workflows/publish.yml uses both shell: sh and shell: bash which is really confusing. I find that conditional does not work at #149 (comment) and I am not sure how to fix it here.

Also see liberfa/pyerfa#111

[ConorMacBride]

The error is happening because the $( ... ) in

env: |
  CIBW_ENVIRONMENT: 'PIP_PRE=$( if [ "${CIBW_BUILD:0:5}" == "cp312" ]; then echo 1; else echo 0; fi )'

is being evaluated before it is passed to cibuildwheel, which it should not, because $CIBW_BUILD is not set at that stage.

I tried escaping it

env: |
  CIBW_ENVIRONMENT: 'PIP_PRE=\$( if [ "\${CIBW_BUILD:0:5}" == "cp312" ]; then echo 1; else echo 0; fi )'

so that it is evaluated inside cibuildwheel, but cibuildwheel then gives an error: https://github.com/ConorMacBride/test-workflows/actions/runs/5944886137/job/16123000921#step:7:279.

Not sure why. I'll take another look at this later.

[pllim]

Thanks for investigating! If this cannot work, then what would be better?

1. Have a new input to set this from workflow interface; or
2. Recommend that people have separate jobs if they need to set CIBW_ENVIRONMENT to different values.