1 files changed, 77 insertions, 0 deletions
diff --git a/weed/wdclient/vid_map_test.go b/weed/wdclient/vid_map_test.go
new file mode 100644
index 000000000..ae4680e7a
--- /dev/null
+++ b/weed/wdclient/vid_map_test.go
@@ -0,0 +1,77 @@
+package wdclient
+
+import (
+	"fmt"
+	"math"
+	"testing"
+)
+
+func TestLocationIndex(t *testing.T) {
+	vm := vidMap{}
+	// test must be failed
+	mustFailed := func(length int64) {
+		_, err := vm.getLocationIndex(length)
+		if err == nil {
+			t.Errorf("length %d must be failed", length)
+		}
+		if err.Error() != fmt.Sprintf("invalid length: %d", length) {
+			t.Errorf("length %d must be failed. error: %v", length, err)
+		}
+	}
+
+	mustFailed(-1)
+	mustFailed(0)
+
+	mustOk := func(length, cursor, expect int64) {
+		if length <= 0 {
+			t.Fatal("please don't do this")
+		}
+		vm.cursor = cursor
+		got, err := vm.getLocationIndex(length)
+		if err != nil {
+			t.Errorf("length: %d, why? %v\n", length, err)
+			return
+		}
+		if got != expect {
+			t.Errorf("cursor: %d, length: %d, expect: %d, got: %d\n", cursor, length, expect, got)
+			return
+		}
+	}
+
+	for i := int64(-1); i < 100; i++ {
+		mustOk(7, i, (i+1)%7)
+	}
+
+	// when cursor reaches MaxInt64
+	mustOk(7, math.MaxInt64, 0)
+
+	// test with constructor
+	vm = newVidMap()
+	length := int64(7)
+	for i := int64(0); i < 100; i++ {
+		got, err := vm.getLocationIndex(length)
+		if err != nil {
+			t.Errorf("length: %d, why? %v\n", length, err)
+			return
+		}
+		if got != i%length {
+			t.Errorf("length: %d, i: %d, got: %d\n", length, i, got)
+		}
+	}
+}
+
+func BenchmarkLocationIndex(b *testing.B) {
+	b.SetParallelism(8)
+	vm := vidMap{
+		cursor: math.MaxInt64 - 10000,
+	}
+	b.ResetTimer()
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			_, err := vm.getLocationIndex(3)
+			if err != nil {
+				b.Error(err)
+			}
+		}
+	})
+}