PR: Don't use hard-coded path to Python in script shebang used to launch Spyder

[Flamefire]

Don't use hard-coded path to python in shebang.

This allows spyder to work in other environments which have python installed in a different directory.

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[ccordoba12]

Hey @Flamefire, thanks for your contribution! Could you describe in which cases this change would be helpful?

It's just that I find a bit strange that this hasn't been reported before by Linux package maintainers.

[Flamefire]

Linux package maintainers.

There they install also Python into the used location, so that isn't an issue.

We are using this in HPC (High Performance Computing) where we install our own Python to control all dependencies and their versions. The python3 binary is in $PATH but not in /usr/bin. This is because we cannot easily change the system images of the nodes but install additional software in global paths.

So when there is only /usr/bin/python3 this does not change anything. When there is another python3 available in $PATH taking precedence then that will be used which allows users to choose which one to use by putting it first in $PATH.

Something concrete for end-users outside our use case: PyEnv. This can be used to install multiple python versions side-by-side and have a command to choose a version for the current shell or globally. This works by having a shim at $HOME/.pyenv/shims/python3 that dispatches to the chosen Python. That also works by putting the shim first in $PATH.
So that would also be enabled by this change.

From what I know it is good practice in general to use the #!/usr/bin/env <command>-style shebang instead of hard-coded paths to allow for such user-control. There might be exceptions of course.

[ccordoba12]

Ok, thanks for the extra info and clarifications @Flamefire. Then I think this is a sensible change and we'll include it in 6.0.2, to be released in a week and a half.

[ccordoba12]

Thanks @Flamefire!

[ccordoba12]

@meeseeksdev please backport to 6.x