Project: datamanagement
Issue DM-5636: Python version checking in newinstall.sh is not quite right
There is a recent report on community where {{newinstall.sh}} reports that the python version is too old despite the user having a modern Anaconda python in their path. In commit e6fc9ed2 the code was changed to check {{$PYTHON}} for version compatibility but that is not correct as the python that will be used for the actual build is the python in their path. {{$PYTHON}} is defined purely as the python to use for EUPS installation. In the reported error {{$PYTHON}} was not set and their {{/usr/bin/python}} was too old. Confusingly the error message reporting the version problem actually reported the version information for the python in the path and not the {{$PYTHON}} python. The simple fix is to revert e6fc9ed2. I already made significant comments on this topic in the original https://github.com/lsst/lsst/pull/19 but I really do have to insist on either reverting that PR or at least fixing the error messages to use a consistent python (I'd argue that this is still wrong but at least consistent). The current situation is at best confusing and at worst pointless and wrong. The version test only makes sense if we are testing that the default python in the path is the correct version to build the stack. {{$PYTHON}} was originally designed to allow a different python to be used to build EUPS. Even that is no longer an issue as EUPS can work with Python >= 2.6 now.
Story points: 1