Re: [PATCH v7 3/4] maintenance: use launchctl on macOS

> [...]
> The need for a user id requires us to run 'id -u' which works on
> POSIX systems but not Windows. Further, the need for fully-qualitifed
> path names including $HOME behaves differently in the Git internals and
> the external test suite. The $HOME variable starts with "C:\..." instead
> of the "/c/..." that is provided by Git in these subcommands. The test
> therefore has a prerequisite that we are not on Windows. The cross-
> platform logic still allows us to test the macOS logic on a Linux
> machine.

> We strive to make these tests work on all platforms, but Windows caused
> some headaches. In particular, the value of getuid() called by the C
> code is not guaranteed to be the same as `$(id -u)` invoked by a test.
> This is because `git.exe` is a native Windows program, whereas the
> utility programs run by the test script mostly utilize the MSYS2 runtime,
> which emulates a POSIX-like environment. Since the purpose of the test
> is to check that the input to the hook is well-formed, the actual user
> ID is immaterial, thus we can work around the problem by making the the
> test UID-agnostic. Another subtle issue is the $HOME environment
> variable being a Windows-style path instead of a Unix-style path. We can
> be more flexible here instead of expecting exact path matches.