fix(proxy): apply custom diff before worker login

Co-Authored-By: Virgil <virgil@lethean.io>

state_impl.go

@@ -56,9 +56,8 @@ func New(cfg *Config) (*Proxy, Result) {
 		shareLog:          newShareLogSink(cfg.ShareLogFile),
 		done:              make(chan struct{}),
 	}
-	p.workers.bindEvents(p.events)
-
 	p.events.Subscribe(EventLogin, p.customDiff.OnLogin)
+	p.workers.bindEvents(p.events)
 	if p.accessLog != nil {
 		p.events.Subscribe(EventLogin, p.accessLog.OnLogin)
 		p.events.Subscribe(EventClose, p.accessLog.OnClose)

worker_test.go

@@ -47,3 +47,38 @@ func TestWorker_NewWorkers_Ugly(t *testing.T) {
 		t.Fatalf("expected a single subscription path, got %d connections", records[0].Connections)
 	}
 }
+
+func TestWorker_CustomDiffOrdering_Good(t *testing.T) {
+	cfg := &Config{
+		Mode:          "nicehash",
+		Workers:       WorkersByUser,
+		Bind:          []BindAddr{{Host: "127.0.0.1", Port: 3333}},
+		Pools:         []PoolConfig{{URL: "pool.example:3333", Enabled: true}},
+		CustomDiff:    50000,
+		AccessLogFile: "",
+	}
+
+	p, result := New(cfg)
+	if !result.OK {
+		t.Fatalf("expected valid proxy, got error: %v", result.Error)
+	}
+
+	miner := &Miner{
+		id:   21,
+		user: "WALLET+50000",
+		ip:   "10.0.0.3",
+		conn: noopConn{},
+	}
+	p.events.Dispatch(Event{Type: EventLogin, Miner: miner})
+
+	records := p.WorkerRecords()
+	if len(records) != 1 {
+		t.Fatalf("expected one worker record, got %d", len(records))
+	}
+	if records[0].Name != "WALLET" {
+		t.Fatalf("expected custom diff login suffix to be stripped before worker registration, got %q", records[0].Name)
+	}
+	if miner.User() != "WALLET" {
+		t.Fatalf("expected miner user to be stripped before downstream consumers, got %q", miner.User())
+	}
+}