options: process project options before machine options

[bonzini]

I'm not sure if this is the right fix or too big a hammer, but let's try.

Fixes: #14608

[bonzini]

Old code indeed used the same order as after the patch. From CoreData.set_default_options:

        options: T.MutableMapping[OptionKey, T.Any] = OrderedDict()
        for k, v in default_options.items(): # process project default options
            if not subproject or k.subproject == subproject:
                options[k] = v
        options.update(env.options)          # override them with machine default and command line options
        env.options = options

[bonzini]

@jpakkane can you confirm that this wasn't intentional?

[jpakkane]

Needs a rebase after #14635.

[dcbaker]

That was merged, a rebase should clear up most or all of the failing tests

[dcbaker]

I'm going to say that even if it was intentional, it's a pretty big behavioral change that, IMHO, would be a breaking backwards incompatible change and require a Meson 2.0 with proper deprecation cycle

[jpakkane]

The documentation says:

You can set some Meson built-in options on a per-subproject basis,
such as `default_library` and `werror`. The order of precedence is:

1) Command line
2) Machine file
3) Build system definitions

So no, the change was not intentional. The new unit test proves that this implementation is correct.

[eli-schwartz]

Suggested change

	prefix = UserStringOption('prefix', 'This is needed by OptionStroe', '/usr')
	prefix = UserStringOption('prefix', 'This is needed by OptionStore', '/usr')

[jpakkane]

With the typo fix + rebase, LGTM.