[Bug]: Apps reload multiple times on save when `--reload` is used

Component

Other

Severity

P3 - Low (minor inconvenience)

Shiny Version

1.4.0

Python Version

3.12

Minimal Reproducible Example

...

Behavior

When I'm working on an app.py file and running it with shiny --reload, saving the file causes shiny to restart two times.

Here's some example output from a single save:

WARNING:  WatchFiles detected changes in 'examples/event/app.py'. Reloading...
INFO:     Shutting down
INFO:     connection closed
INFO:     Waiting for application shutdown.
INFO:     Application shutdown complete.
INFO:     Finished server process [39459]
INFO:     Started server process [40731]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     127.0.0.1:58860 - "GET /?_positronRender%3D5 HTTP/1.1" 200 OK
INFO:     ('127.0.0.1', 58863) - "WebSocket /websocket/" [accepted]
INFO:     connection open
WARNING:  WatchFiles detected changes in 'examples/event/app.py'. Reloading...
INFO:     Shutting down
INFO:     connection closed
INFO:     Waiting for application shutdown.
INFO:     Application shutdown complete.
INFO:     Finished server process [40731]
INFO:     Started server process [40733]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     127.0.0.1:58870 - "GET /?_positronRender%3D5 HTTP/1.1" 200 OK
INFO:     ('127.0.0.1', 58873) - "WebSocket /websocket/" [accepted]
INFO:     connection open

Error Messages (if any)

Environment

Mac

Start by reproducing the issue with shiny --reload while saving examples/event/app.py, using the provided restart logs as the expected failure pattern. Trace the reload entry point and verify that one save produces only one shutdown and restart; there is no specific source file or test named in the report.