I can set the configuration properly from an environment variable.
But there are a number of tests that then reach out into the environment and try to reconfigure the source or otherwise read information.
These are test-program.script test-try-refinding.script test-utilities.script
None of these work properly when Lisp is running under cygwin.
I'm inclined to think that this is an ASDF+Windows problem, and not a problem to be fixed in the tests. If you run a Lisp under cygwin, and you call some of these functions, they should simply error out, because the cygwin environment is going to give the lisp pathnames that it can't handle.
Further, (a) we don't know how to call out to cygwin; (b) we can't call out to CMD.EXE when running under cygwin, because we have a polluted environment; and (c) UIOP cannot detect when it is running under cygwin.
Under the circumstances, RUN-PROGRAM simply doesn't run reliably under cygwin. Worse, since we can't detect Cygwin, we really can't reliably run under windows at all, since we don't know when these functions will and won't work.
This suggests the following:
1. We desperately need ASDF to be able to detect when it's running under cygwin, so it can at least error out when it's going to function wrong.
2. I don't know how to program make.bat. I will not be learning how to program make.bat. The test scripts that I can run are shell scripts. I have not been able to make Fare's lisp build and test scripts work and I am no longer trying to make them work at all, ever, anywhere. I don't believe they work any better under Cygwin, anyway.
Ergo, if ASDF works on Windows, it will only be a matter of luck.
Ergo, ASDF needs a windows tester and maintainer. I quite simply decline to perform this function. Someone who wants ASDF to work on Windows should step up.
Unless someone steps up by the end of March, all further ASDF releases, starting with 3.1.7 will be officially Windows non-supporting. Windows patches and bug reports will be accepted. I will not make any attempt to fix Windows ASDF bugs myself. I will make only those Windows tests that I can make under Cygwin.