Should GamsDirFinder prefer where/which gams to environment variable values?

[elainethale]

Currently GamsDirFinder.__find_gams looks for GAMS in this order:

• GAMS_DIR environment variable
• GAMSDIR environment variable
• where / which gams
• default install location (Windows only)

Should where/which gams come first? This would change behavior/break interface, but might be more aligned with expected behavior, in that GamsDirFinder would find the version of GAMS that is also found by the command line by default.

[jebob]

I think it is a good idea. I trust PATH more than GAMSDIR.

[jebob]

Should also consider speed, subprocess into where/which might be slower.

EDIT 2023-05-17: I no longer think that this will be a significant slowdown compared to anything else.