[10.x] Ensures connections only listen for their own events

[timacdonald]

The Connection::listen() method currently listens to queries on any connection.

DB::connection('mysql')->listen(function () {
    dump('mysql query run');
});

DB::connection('sqlite')->listen(function () {
    dump('sqlite query run');
});

DB::connection('sqlite')->table('foo')->select('*');

// output:
// "mysql query run"
// "sqlite query run"

This is a bug and unexpected behaviour that is potentially problematic. It also impacts other framework behaviour that depends on adding listeners to the specific connection, e.g. the query duration handlers.

[timacdonald]

This is an identity check. I felt this was better than checking the connection name.

If you change the driver instance, it feels like you would want to also remove the listeners.

[taylorotwell]

I don't think we could change this on a patch release. Most likely people are already depending on this "bug" in the wild pretty heavily. The event contains the connection name so it is possible to check what connection you are listening on.