Formal specification for context / expression (IE if) language?

Hi!

Is there an formal (computer readable) specification for the context and expression syntax for GitHub Actions?

From what I can tell, it seems to be some type of subset of Javascript but that is never explicitly stated.

Thanks!

Tim ‘mithro’ Ansell

The answer is probably no, but you could check if any of the VS Code extensions for GitHub Actions has something that is of use to you: This one has auto-complete for expressions, for instance: