Is there a way to know if a dispatch command opens a dialog?

[sbergman@xxxxxxxxxx (Stephan Bergmann)]

On 02/08/18 10:30, Heiko Tietze wrote:
> Worst workaround ever: test the command label for ellipsis. But only the bravest trust design/l10n ;-)

...but where lack of ellipsis doesn't necessarily imply that no dialog 
gets shown, right?  At least, 
<https://stackoverflow.com/questions/637683/when-to-use-ellipsis-after-menu-items#637708> 
matches my understanding of how that concept should be used.