Sure it's not often considered a part of the definition of a CDN, but version management very much is the duty of a good CDN (even just as a part of cache management to know when to clear/refresh caches).
A CDN built for public usage (ie, that you do not run yourself DIY style, and isn't a corporate internal CDN they don't expect outsiders to reuse) that is built to serve JS (and often CSS, too) will through necessity provide some versioning mechanism. As I said, if you find a CDN that is serving JS files and doesn't have some sort of versioning mechanism or policy in place then you find a better CDN. I think at this point good versions strategies is a requirement for a good CDN.
Take MaxCDN as a good example since it is one of the most common CDNs at this point for JS/CSS (Bootstrap, Font Awesome, Twemoji, ...): all of their URLs have version numbers in their path structure (/bootstrap/3.3.7/...).
RawGit is probably the next most common I see, thanks to it making it very easy for anyone to CDN access a GitHub repo. As I mentioned before: RawGit uses git branches and tags in its folder structure for version management. If you are using a RawGit URL with /master/ in the URL you should switch to a version tag pronto (and that's not RawGit's fault, it's yours for giving it a floating version requirement).
A CDN built for public usage (ie, that you do not run yourself DIY style, and isn't a corporate internal CDN they don't expect outsiders to reuse) that is built to serve JS (and often CSS, too) will through necessity provide some versioning mechanism. As I said, if you find a CDN that is serving JS files and doesn't have some sort of versioning mechanism or policy in place then you find a better CDN. I think at this point good versions strategies is a requirement for a good CDN.
Take MaxCDN as a good example since it is one of the most common CDNs at this point for JS/CSS (Bootstrap, Font Awesome, Twemoji, ...): all of their URLs have version numbers in their path structure (/bootstrap/3.3.7/...).
RawGit is probably the next most common I see, thanks to it making it very easy for anyone to CDN access a GitHub repo. As I mentioned before: RawGit uses git branches and tags in its folder structure for version management. If you are using a RawGit URL with /master/ in the URL you should switch to a version tag pronto (and that's not RawGit's fault, it's yours for giving it a floating version requirement).