Re: Inconsistency in PHP 8.5 deprecation of terminating case with semicolon

On Tue, October 14 2025 at 18:08 Juliette Reinders Folmer wrote: > Dear Theodore and list, > > I've been looking into the "Deprecate semicolon after case in switch statement" > PHP 8.5 deprecation [1] > with the aim of adding a sniff for this to the PHPCompatibility standard and I'm noticing > an oddity for > which I would like to clarify whether this is intentional or an oversight.. > > As demonstrated in the example code provided in the deprecation RFC, both switch > case condition > statements, as well as default statements, can be ended with a > semicolon. > > So when I first read the RFC, I interpreted the proposal to include both > case as well as default, > as, in my mind, default is just a special > case in a switch. > > However, the RFC explicitly only talked about deprecating the use of a semicolon after a > case statement and the implementation has followed this to the > letter. [2] > > The net result of this, is that you can now have a switch > statement with semicolons > terminating case statements and > default statements, where the former > (case) will > result in a deprecation notice, while the latter (default) will > not. For an example, see [3] > > This feels inconsistent to me and counter to the intention of the RFC, which is stated to be: > >> Case statements followed by a semicolon can cause confusion, as a developer may think they >> behave differently in some way from regular case statements (e.g. preventing fallthrough), >> when they do not. > > Which leaves me wondering what the reason was not to _also_ deprecate the use of a semicolon > to terminate a default statement in a switch ? I can't > find any discussion about this in the > original mailing list thread [4]. > > Anyone would care to clarify ? Hi Juliette, Thank you for pointing out the discrepancy. You are correct that default is just a special case statement, and the intention in the RFC was to output the deprecation message for default cases as well (the example in the RFC included a default case followed by a semicolon to highlight this). The fact that a deprecation message isn't shown for default cases is an oversight on my part when I implemented the RFC. The merged implementation correctly updated the AST for default case statements followed by a semicolon to support the deprecation message, but I failed to notice that when the compiler code loops over switch cases, there is a continue statement when handling the default case which prevents reaching the code for the deprecation. I opened a follow-up pull request to fix this, which can hopefully be merged before PHP 8.5 is released: https://github.com/php/php-src/pull/20172 Kind regards, Theodore > > Smile, > Juliette > > [1]: > https://wiki.php.net/rfc/deprecations_php_8_5#deprecate_semicolon_after_case_in_switch_statement > [2]: > https://github.com/php/php-src/commit/5f8d648af6ef4e29a3c7f2b2029d08466c12bc6f > [3]: https://3v4l.org/liFIK/rfc#vgit.master > [4]: https://externals.io/message/126000