For a single file plugin with a text domain set, the WordPress.WP.I18n.TextDomainMismatch check relies on a plugin directory slug (non-existent in this context) and shows different results between the UI and CLI. It has been suggested that this check be bypassed for single-file plugins (hat tip @ernilambar).

To test this, I added the hello-dolly text domain to the hello.php plugin that ships with WP core (required to avoid an error with the WordPress.WP.I18n.MissingArgDomain check):

__( 'Quote from Hello Dolly song, by Jerry Herman:', 'hello-dolly' ),

Running PCP, the admin shows
Mismatched text domain. Expected 'plugins' but got 'hello-dolly'.
whereas the CLI returns
Mismatched text domain. Expected 'hello.php' but got 'hello-dolly'.

Originally reported at #713 (comment).