fix test

weed/util/chunk_cache/chunk_cache_on_disk_test.go

@@ -49,6 +49,24 @@ func TestOnDisk(t *testing.T) {
 		}
 	}
 
+	for i := 2; i < writeCount; i++ {
+		data := cache.GetChunk(testData[i].fileId, testData[i].size)
+		if bytes.Compare(data, testData[i].data) != 0 {
+			t.Errorf("failed to write to and read from cache: %d", i)
+		}
+	}
+
+	cache.Shutdown()
+
+	cache = NewTieredChunkCache(2, tmpDir, totalDiskSizeInKB, 1024)
+
+	for i := 0; i < 2; i++ {
+		data := cache.GetChunk(testData[i].fileId, testData[i].size)
+		if bytes.Compare(data, testData[i].data) == 0 {
+			t.Errorf("old cache should have been purged: %d", i)
+		}
+	}
+
 	for i := 2; i < writeCount; i++ {
 		if i == 4 {
 			// FIXME this failed many times on build machines
@@ -77,22 +95,4 @@ func TestOnDisk(t *testing.T) {
 
 	cache.Shutdown()
 
-	cache = NewTieredChunkCache(2, tmpDir, totalDiskSizeInKB, 1024)
-
-	for i := 0; i < 2; i++ {
-		data := cache.GetChunk(testData[i].fileId, testData[i].size)
-		if bytes.Compare(data, testData[i].data) == 0 {
-			t.Errorf("old cache should have been purged: %d", i)
-		}
-	}
-
-	for i := 2; i < writeCount; i++ {
-		data := cache.GetChunk(testData[i].fileId, testData[i].size)
-		if bytes.Compare(data, testData[i].data) != 0 {
-			t.Errorf("failed to write to and read from cache: %d", i)
-		}
-	}
-
-	cache.Shutdown()
-
 }