[RomainLanz]

Hey! 👋

When a controller changes in HMR mode, the dev server calls RoutesScanner.invalidate() to recompute the request and response types of its routes. This method created a new VirtualFileSystem for each route bound to the controller. Each instance starts with an empty AST cache, so the same file was read and parsed with ast-grep once per route.

This PR creates the VirtualFileSystem once before the loop, as scan() already does. Each call still creates a new instance, so an invalidation always reads the latest file contents.

Benchmark

Node.js 26.10, single core, public RoutesScanner API: scan(), then time invalidate(controllerPath). Generated controllers with and without VineJS validators. Each variant ran in 5 independent processes with 20 warmups and 40 measured calls. Execution order alternated between variants. Values are the median of the per-process medians.

Controller	Routes	Before	After	Parses per call
50 lines	1	3.6 ms	3.5 ms	1 → 1
50 lines	7	8.5 ms	4.4 ms	7 → 1
200 lines	3	17.0 ms	12.0 ms	3 → 1
200 lines	7	41.2 ms	22.2 ms	7 → 1
500 lines	7	90.4 ms	43.0 ms	7 → 1
1000 lines	7	198 ms	59.7 ms	7 → 1

There is no change with 1 route. With 3 routes the call is 1.2× to 2× faster, and with 7 routes 1.7× to 3.3× faster.

In a real app created with create-adonisjs -K=api (HMR mode, Tuyau generateRegistry hook), on a 36-line controller with 7 routes, the registry is up to date 18 ms after the save instead of 28 ms. The HTTP response is not affected: #reScanRoutes is not awaited and runs in the dev server process, so the hot reload takes about 30 ms in both cases. In watch mode, a controller change restarts the server and invalidate() is not called.

For typical controllers this is a small cleanup, not a visible speedup.

Validation

• getScannedRoutes() is identical before and after the change, for 50 controller configurations (50 to 2000 lines, 1 to 30 routes, with and without validators). Compared after scan(), after invalidate(), and after a file edit followed by invalidate().
• 295 tests passed
• Typecheck passed
• ESLint passed
• git diff --check passed

Not covered: no new test checks how many times the file is parsed. The existing routes scanner tests cover the output.