text-domain is not parsed correctly when theme has no i18n translation

[latracal]

Initially reported in #themereview channel - https://wordpress.slack.com/archives/C02RP4Y3K/p1662993132324669 (requires login).

When theme has no i18n translation, the Theme Check fails with the message -
REQUIRED: This theme text domain does not match the theme's slug. The text domain used: This theme's correct slug and text-domain is no-i18n.

Further, the INFO log for text-domain seems to be rendering an empty text-domain (Notice the 'domain found is .' part) -
INFO: Only one text-domain is being used in this theme. Make sure it matches the theme's slug correctly so that the theme will be compatible with WordPress.org language packs. The domain found is .

== Testing Environment ==
PHP Version: 8.1.4
WordPress Version: 6.0.2
Theme Check Version: 20211203
Theme Slug: no-i18n

== To Replicate ==
I've created a basic theme with no translation to test this out quickly.
Repository - no-i18n
Theme Download Link - no-i18n.zip

[justintadlock]

I'll try to dive into this a bit more when I get a chance, but I believe we need to check whether $domains is empty here: https://github.com/WordPress/theme-check/blob/master/checks/class-textdomain-check.php#L215

Probably something like:

if ( ! empty( $domains ) && ! in_array( $correct_domain, $domains ) ) {

I'm not familiar enough with the internals of TC to know if that'll blow something else up yet.

[dd32]

Was this resolved by #435?