[优化] go 引用调整

openflare-server/service/observability_trends_test.go

@@ -0,0 +1,33 @@
+package service
+
+import (
+	"testing"
+	"time"
+
+	"github.com/rain-kl/openflare/openflare-server/model"
+)
+
+func TestBuildDiskIOTrendPointsUsesCounterDelta(t *testing.T) {
+	now := time.Date(2026, 3, 14, 18, 30, 0, 0, time.UTC)
+	start := trendWindowStart(now)
+
+	points := buildDiskIOTrendPoints(now, []*model.NodeMetricSnapshot{
+		{
+			NodeID:         "node-a",
+			CapturedAt:     start.Add(22 * time.Hour),
+			DiskReadBytes:  100,
+			DiskWriteBytes: 200,
+		},
+		{
+			NodeID:         "node-a",
+			CapturedAt:     start.Add(23 * time.Hour),
+			DiskReadBytes:  250,
+			DiskWriteBytes: 260,
+		},
+	})
+
+	last := points[len(points)-1]
+	if last.DiskReadBytes != 150 || last.DiskWriteBytes != 60 {
+		t.Fatalf("expected disk io trend to use counter delta, got %+v", last)
+	}
+}