merged from gramsrv upstream

internal/loadharness/client_test.go

@@ -0,0 +1,60 @@
+package loadharness
+
+import (
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/iamxvbaba/td/proto"
+)
+
+func TestLoadMessageIDSourceSkipsEmptyClientFraction(t *testing.T) {
+	second := time.Unix(1_800_000_000, 0)
+	source := newLoadMessageIDSource(func() time.Time { return second })
+
+	first := source.New(proto.MessageFromClient)
+	secondID := source.New(proto.MessageFromClient)
+	for index, messageID := range []int64{first, secondID} {
+		if uint32(messageID) == 0 {
+			t.Fatalf("message id %d lower 32 bits are empty", index)
+		}
+		if proto.MessageID(messageID).Type() != proto.MessageFromClient {
+			t.Fatalf("message id %d type = %v, want client", index, proto.MessageID(messageID).Type())
+		}
+	}
+	if secondID <= first {
+		t.Fatalf("message ids are not strictly increasing: %d then %d", first, secondID)
+	}
+}
+
+func TestLoadMessageIDSourceConcurrentMonotonicUnique(t *testing.T) {
+	second := time.Unix(1_800_000_000, 0)
+	source := newLoadMessageIDSource(func() time.Time { return second })
+
+	const calls = 1_000
+	ids := make(chan int64, calls)
+	var workers sync.WaitGroup
+	workers.Add(calls)
+	for range calls {
+		go func() {
+			defer workers.Done()
+			ids <- source.New(proto.MessageFromClient)
+		}()
+	}
+	workers.Wait()
+	close(ids)
+
+	seen := make(map[int64]struct{}, calls)
+	for messageID := range ids {
+		if uint32(messageID) == 0 || proto.MessageID(messageID).Type() != proto.MessageFromClient {
+			t.Fatalf("invalid client message id %d", messageID)
+		}
+		if _, duplicate := seen[messageID]; duplicate {
+			t.Fatalf("duplicate client message id %d", messageID)
+		}
+		seen[messageID] = struct{}{}
+	}
+	if len(seen) != calls {
+		t.Fatalf("unique message ids = %d, want %d", len(seen), calls)
+	}
+}