add size() unit test

Author: zhangzqs

src/test/java/test/com/qiniu/storage/BucketManagerTest.java

@@ -0,0 +1,27 @@
+package test.com.qiniu.storage;
+
+import com.qiniu.storage.BucketManager;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+
+public class BucketManagerTest {
+    @Test
+    @Tag("UnitTest")
+    public void testBatchOperationsSize() {
+        BucketManager.BatchOperations batchOperations = new BucketManager.BatchOperations();
+        Assertions.assertEquals(0, batchOperations.size());
+
+        batchOperations.addDeleteOp("bucket1", "1", "2");
+        Assertions.assertEquals(2, batchOperations.size());
+
+        batchOperations.addCopyOp(
+                "fromBucket", "fromFileKey",
+                "toBucket", "toFileKey"
+        );
+        Assertions.assertEquals(3, batchOperations.size());
+
+        batchOperations.addRenameOp("fromBucket", "fromFileKey", "toFileKey");
+        Assertions.assertEquals(4, batchOperations.size());
+    }
+}