Fix babel register cache invalidation

[cha0s]

Incredibly, @babel/register wasn't caching anything. This is because setDirty() must be called on the worker cache, otherwise the check at https://github.com/babel/babel/blob/main/packages/babel-register/src/worker/cache.js#L32 always fails.

I couldn't believe it when I started digging into why caching seemed to do nothing. Lazy! ;)

Q	A
Fixed Issues?	Shockingly, no one seems to have noticed until now?
Patch: Bug Fix?	Yes
Major: Breaking Change?	No
Minor: New Feature?	No
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?	No
License	MIT

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/51357/

[cha0s]

Figured I'd attach a patch-package patch here for anyone following along:

diff --git a/node_modules/@babel/register/lib/worker/transform.js b/node_modules/@babel/register/lib/worker/transform.js
index 8a1cef0..c30688d 100644
--- a/node_modules/@babel/register/lib/worker/transform.js
+++ b/node_modules/@babel/register/lib/worker/transform.js
@@ -137,6 +137,7 @@ function cacheLookup(opts, filename) {
         value,
         mtime: fileMtime
       };
+      registerCache.setDirty();
       return value;
     }

My build time halved in the moderately-sized project that I've tested so far.

[nicolo-ribaudo]

Whops, thanks!