Added tests

gcsio/src/main/java/com/google/cloud/hadoop/gcsio/ZeroCopyMessageMarshaller.java

@@ -97,6 +97,7 @@ public T parse(InputStream stream) {
         try {
           message = parseFrom(codedInputStream);
         } catch (InvalidProtocolBufferException ipbe) {
+          stream.close();
           throw Status.INTERNAL
               .withDescription("Invalid protobuf byte sequence")
               .withCause(ipbe)

gcsio/src/test/java/com/google/cloud/hadoop/gcsio/ZeroCopyMessageMarshallerTest.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright 2021 Google Inc. All Rights Reserved.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.cloud.hadoop.gcsio;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
+
+import com.google.google.storage.v1.GetObjectRequest;
+import io.grpc.StatusRuntimeException;
+import io.grpc.internal.ReadableBuffer;
+import io.grpc.internal.ReadableBuffers;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class ZeroCopyMessageMarshallerTest {
+  private GetObjectRequest REQUEST =
+      GetObjectRequest.newBuilder().setBucket("b").setObject("o").build();
+
+  private ZeroCopyMessageMarshaller<GetObjectRequest> createMarshaller() {
+    return new ZeroCopyMessageMarshaller<>(GetObjectRequest.getDefaultInstance());
+  }
+
+  private byte[] dropLastOneByte(byte[] bytes) {
+    return Arrays.copyOfRange(bytes, 0, bytes.length - 1);
+  }
+
+  private InputStream createInputStream(byte[] bytes, boolean isZeroCopyable) {
+    ReadableBuffer buffer =
+        isZeroCopyable ? ReadableBuffers.wrap(ByteBuffer.wrap(bytes)) : ReadableBuffers.wrap(bytes);
+    return ReadableBuffers.openStream(buffer, true);
+  }
+
+  @Test
+  public void testParseOnFastPath() throws IOException {
+    InputStream stream = createInputStream(REQUEST.toByteArray(), true);
+    ZeroCopyMessageMarshaller<GetObjectRequest> marshaller = createMarshaller();
+    GetObjectRequest request = marshaller.parse(stream);
+    assertThat(request).isEqualTo(REQUEST);
+    InputStream stream2 = marshaller.popStream(request);
+    assertThat(stream2).isNotNull();
+    stream2.close();
+    InputStream stream3 = marshaller.popStream(request);
+    assertThat(stream3).isNull();
+  }
+
+  @Test
+  public void testParseOnSlowPath() {
+    InputStream stream = createInputStream(REQUEST.toByteArray(), false);
+    ZeroCopyMessageMarshaller<GetObjectRequest> marshaller = createMarshaller();
+    GetObjectRequest request = marshaller.parse(stream);
+    assertThat(request).isEqualTo(REQUEST);
+    InputStream stream2 = marshaller.popStream(request);
+    assertThat(stream2).isNull();
+  }
+
+  @Test
+  public void testParseBrokenMessageOnFastPath() {
+    InputStream stream = createInputStream(dropLastOneByte(REQUEST.toByteArray()), true);
+    ZeroCopyMessageMarshaller<GetObjectRequest> marshaller = createMarshaller();
+    assertThrows(
+        StatusRuntimeException.class,
+        () -> {
+          marshaller.parse(stream);
+        });
+  }
+
+  @Test
+  public void testParseBrokenMessageOnSlowPath() {
+    InputStream stream = createInputStream(dropLastOneByte(REQUEST.toByteArray()), false);
+    ZeroCopyMessageMarshaller<GetObjectRequest> marshaller = createMarshaller();
+    assertThrows(
+        StatusRuntimeException.class,
+        () -> {
+          marshaller.parse(stream);
+        });
+  }
+}