Since 0.59.0, meson automatically activates Visual Studio environment on Windows for all its subcommands, but only if no other compilers (e.g. gcc or clang) are found, and silently continue if Visual Studio activation fails.
meson setup --vsenv command line argument can now be used to force Visual Studio activation even when other compilers are found. It also make Meson abort with an error message when activation fails. This is especially useful for Github Action because their Windows images have gcc in their PATH by default.
--vsenv is set by default when using vs backend.
Only setup, compile, dist and devenv subcommands now activate Visual Studio.