package org.eclipse.jgit.transport;
   
   import static org.hamcrest.MatcherAssert.assertThat;
   import static org.hamcrest.Matchers.containsInAnyOrder;
   import static org.hamcrest.Matchers.containsString;
   import static org.hamcrest.Matchers.hasItems;
   import static org.hamcrest.Matchers.is;
   import static org.hamcrest.Matchers.notNullValue;
   import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertThrows;
  import static org.junit.Assert.assertTrue;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.StringWriter;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Objects;
  import java.util.function.Consumer;
  
  import org.eclipse.jgit.dircache.DirCache;
  import org.eclipse.jgit.dircache.DirCacheBuilder;
  import org.eclipse.jgit.dircache.DirCacheEntry;
  import org.eclipse.jgit.errors.TransportException;
  import org.eclipse.jgit.internal.storage.dfs.DfsGarbageCollector;
  import org.eclipse.jgit.internal.storage.dfs.DfsRepositoryDescription;
  import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
  import org.eclipse.jgit.internal.storage.file.PackLock;
  import org.eclipse.jgit.internal.storage.pack.CachedPack;
  import org.eclipse.jgit.internal.storage.pack.CachedPackUriProvider;
  import org.eclipse.jgit.junit.TestRepository;
  import org.eclipse.jgit.lib.NullProgressMonitor;
  import org.eclipse.jgit.lib.ObjectId;
  import org.eclipse.jgit.lib.ObjectInserter;
  import org.eclipse.jgit.lib.PersonIdent;
  import org.eclipse.jgit.lib.ProgressMonitor;
  import org.eclipse.jgit.lib.Ref;
  import org.eclipse.jgit.lib.RefDatabase;
  import org.eclipse.jgit.lib.Repository;
  import org.eclipse.jgit.lib.Sets;
  import org.eclipse.jgit.lib.TextProgressMonitor;
  import org.eclipse.jgit.revwalk.RevBlob;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.eclipse.jgit.revwalk.RevTag;
  import org.eclipse.jgit.revwalk.RevTree;
  import org.eclipse.jgit.storage.pack.PackStatistics;
  import org.eclipse.jgit.transport.UploadPack.RequestPolicy;
  import org.eclipse.jgit.util.io.NullOutputStream;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  
  /**
   * Tests for server upload-pack utilities.
   */
  public class UploadPackTest {
  	private URIish uri;
  
  	private TestProtocol<Object> testProtocol;
  
  	private final Object ctx = new Object();
  
  	private InMemoryRepository server;
  
  	private InMemoryRepository client;
  
  	private TestRepository<InMemoryRepository> remote;
  
  	private PackStatistics stats;
  
  	@Before
  	public void setUp() throws Exception {
  		server = newRepo("server");
  		client = newRepo("client");
  
  		remote = new TestRepository<>(server);
  	}
  
  	@After
  	public void tearDown() {
  		Transport.unregister(testProtocol);
  	}
  
  	private static InMemoryRepository newRepo(String name) {
  		return new InMemoryRepository(new DfsRepositoryDescription(name));
  	}
  
  	private void generateBitmaps(InMemoryRepository repo) throws Exception {
  		new DfsGarbageCollector(repo).pack(null);
  		repo.scanForRepoChanges();
 	}
 
 	@Test
 	public void testFetchParentOfShallowCommit() throws Exception {
 		RevCommit commit0 = remote.commit().message("0").create();
 		RevCommit commit1 = remote.commit().message("1").parent(commit0).create();
 		RevCommit tip = remote.commit().message("2").parent(commit1).create();
 		remote.update("master", tip);
 
 		testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 			UploadPack up = new UploadPack(db);
 			up.setRequestPolicy(RequestPolicy.REACHABLE_COMMIT);
 			// assume client has a shallow commit
 			up.getRevWalk()
 					.assumeShallow(Collections.singleton(commit1.getId()));
 			return up;
 		}, null);
 		uri = testProtocol.register(ctx, server);
 
 		assertFalse(client.getObjectDatabase().has(commit0.toObjectId()));
 
 		// Fetch of the parent of the shallow commit
 		try (Transport tn = testProtocol.open(uri, client, "server")) {
 			tn.fetch(NullProgressMonitor.INSTANCE,
 					Collections.singletonList(new RefSpec(commit0.name())));
 			assertTrue(client.getObjectDatabase().has(commit0.toObjectId()));
 		}
 	}
 
 	@Test
 	public void testFetchWithBlobNoneFilter() throws Exception {
 		InMemoryRepository server2 = newRepo("server2");
 		try (TestRepository<InMemoryRepository> remote2 = new TestRepository<>(
 				server2)) {
 			RevBlob blob1 = remote2.blob("foobar");
 			RevBlob blob2 = remote2.blob("fooba");
 			RevTree tree = remote2.tree(remote2.file("1", blob1),
 					remote2.file("2", blob2));
 			RevCommit commit = remote2.commit(tree);
 			remote2.update("master", commit);
 
 			server2.getConfig().setBoolean("uploadpack", null, "allowfilter",
 					true);
 
 			testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 				UploadPack up = new UploadPack(db);
 				return up;
 			}, null);
 			uri = testProtocol.register(ctx, server2);
 
 			try (Transport tn = testProtocol.open(uri, client, "server2")) {
 				tn.setFilterSpec(FilterSpec.withBlobLimit(0));
 				tn.fetch(NullProgressMonitor.INSTANCE,
 						Collections.singletonList(new RefSpec(commit.name())));
 				assertTrue(client.getObjectDatabase().has(tree.toObjectId()));
 				assertFalse(client.getObjectDatabase().has(blob1.toObjectId()));
 				assertFalse(client.getObjectDatabase().has(blob2.toObjectId()));
 			}
 		}
 	}
 
 	@Test
 	public void testFetchExplicitBlobWithFilter() throws Exception {
 		InMemoryRepository server2 = newRepo("server2");
 		try (TestRepository<InMemoryRepository> remote2 = new TestRepository<>(
 				server2)) {
 			RevBlob blob1 = remote2.blob("foobar");
 			RevBlob blob2 = remote2.blob("fooba");
 			RevTree tree = remote2.tree(remote2.file("1", blob1),
 					remote2.file("2", blob2));
 			RevCommit commit = remote2.commit(tree);
 			remote2.update("master", commit);
 			remote2.update("a_blob", blob1);
 
 			server2.getConfig().setBoolean("uploadpack", null, "allowfilter",
 					true);
 
 			testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 				UploadPack up = new UploadPack(db);
 				return up;
 			}, null);
 			uri = testProtocol.register(ctx, server2);
 
 			try (Transport tn = testProtocol.open(uri, client, "server2")) {
 				tn.setFilterSpec(FilterSpec.withBlobLimit(0));
 				tn.fetch(NullProgressMonitor.INSTANCE, Arrays.asList(
 						new RefSpec(commit.name()), new RefSpec(blob1.name())));
 				assertTrue(client.getObjectDatabase().has(tree.toObjectId()));
 				assertTrue(client.getObjectDatabase().has(blob1.toObjectId()));
 				assertFalse(client.getObjectDatabase().has(blob2.toObjectId()));
 			}
 		}
 	}
 
 	@Test
 	public void testFetchWithBlobLimitFilter() throws Exception {
 		InMemoryRepository server2 = newRepo("server2");
 		try (TestRepository<InMemoryRepository> remote2 = new TestRepository<>(
 				server2)) {
 			RevBlob longBlob = remote2.blob("foobar");
 			RevBlob shortBlob = remote2.blob("fooba");
 			RevTree tree = remote2.tree(remote2.file("1", longBlob),
 					remote2.file("2", shortBlob));
 			RevCommit commit = remote2.commit(tree);
 			remote2.update("master", commit);
 
 			server2.getConfig().setBoolean("uploadpack", null, "allowfilter",
 					true);
 
 			testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 				UploadPack up = new UploadPack(db);
 				return up;
 			}, null);
 			uri = testProtocol.register(ctx, server2);
 
 			try (Transport tn = testProtocol.open(uri, client, "server2")) {
 				tn.setFilterSpec(FilterSpec.withBlobLimit(5));
 				tn.fetch(NullProgressMonitor.INSTANCE,
 						Collections.singletonList(new RefSpec(commit.name())));
 				assertFalse(
 						client.getObjectDatabase().has(longBlob.toObjectId()));
 				assertTrue(
 						client.getObjectDatabase().has(shortBlob.toObjectId()));
 			}
 		}
 	}
 
 	@Test
 	public void testFetchExplicitBlobWithFilterAndBitmaps() throws Exception {
 		InMemoryRepository server2 = newRepo("server2");
 		try (TestRepository<InMemoryRepository> remote2 = new TestRepository<>(
 				server2)) {
 			RevBlob blob1 = remote2.blob("foobar");
 			RevBlob blob2 = remote2.blob("fooba");
 			RevTree tree = remote2.tree(remote2.file("1", blob1),
 					remote2.file("2", blob2));
 			RevCommit commit = remote2.commit(tree);
 			remote2.update("master", commit);
 			remote2.update("a_blob", blob1);
 
 			server2.getConfig().setBoolean("uploadpack", null, "allowfilter",
 					true);
 
 			// generate bitmaps
 			new DfsGarbageCollector(server2).pack(null);
 			server2.scanForRepoChanges();
 
 			testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 				UploadPack up = new UploadPack(db);
 				return up;
 			}, null);
 			uri = testProtocol.register(ctx, server2);
 
 			try (Transport tn = testProtocol.open(uri, client, "server2")) {
 				tn.setFilterSpec(FilterSpec.withBlobLimit(0));
 				tn.fetch(NullProgressMonitor.INSTANCE, Arrays.asList(
 						new RefSpec(commit.name()), new RefSpec(blob1.name())));
 				assertTrue(client.getObjectDatabase().has(blob1.toObjectId()));
 				assertFalse(client.getObjectDatabase().has(blob2.toObjectId()));
 			}
 		}
 	}
 
 	@Test
 	public void testFetchWithBlobLimitFilterAndBitmaps() throws Exception {
 		InMemoryRepository server2 = newRepo("server2");
 		try (TestRepository<InMemoryRepository> remote2 = new TestRepository<>(
 				server2)) {
 			RevBlob longBlob = remote2.blob("foobar");
 			RevBlob shortBlob = remote2.blob("fooba");
 			RevTree tree = remote2.tree(remote2.file("1", longBlob),
 					remote2.file("2", shortBlob));
 			RevCommit commit = remote2.commit(tree);
 			remote2.update("master", commit);
 
 			server2.getConfig().setBoolean("uploadpack", null, "allowfilter",
 					true);
 
 			// generate bitmaps
 			new DfsGarbageCollector(server2).pack(null);
 			server2.scanForRepoChanges();
 
 			testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 				UploadPack up = new UploadPack(db);
 				return up;
 			}, null);
 			uri = testProtocol.register(ctx, server2);
 
 			try (Transport tn = testProtocol.open(uri, client, "server2")) {
 				tn.setFilterSpec(FilterSpec.withBlobLimit(5));
 				tn.fetch(NullProgressMonitor.INSTANCE,
 						Collections.singletonList(new RefSpec(commit.name())));
 				assertFalse(
 						client.getObjectDatabase().has(longBlob.toObjectId()));
 				assertTrue(
 						client.getObjectDatabase().has(shortBlob.toObjectId()));
 			}
 		}
 	}
 
 	@Test
 	public void testFetchWithNonSupportingServer() throws Exception {
 		InMemoryRepository server2 = newRepo("server2");
 		try (TestRepository<InMemoryRepository> remote2 = new TestRepository<>(
 				server2)) {
 			RevBlob blob = remote2.blob("foo");
 			RevTree tree = remote2.tree(remote2.file("1", blob));
 			RevCommit commit = remote2.commit(tree);
 			remote2.update("master", commit);
 
 			server2.getConfig().setBoolean("uploadpack", null, "allowfilter",
 					false);
 
 			testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 				UploadPack up = new UploadPack(db);
 				return up;
 			}, null);
 			uri = testProtocol.register(ctx, server2);
 
 			try (Transport tn = testProtocol.open(uri, client, "server2")) {
 				tn.setFilterSpec(FilterSpec.withBlobLimit(0));
 
 				TransportException e = assertThrows(TransportException.class,
 						() -> tn.fetch(NullProgressMonitor.INSTANCE, Collections
 								.singletonList(new RefSpec(commit.name()))));
 				assertThat(e.getMessage(), containsString(
 						"filter requires server to advertise that capability"));
 			}
 		}
 	}
 
 	/*
 	 * Invokes UploadPack with protocol v2 and sends it the given lines,
 	 * and returns UploadPack's output stream.
 	 */
 	private ByteArrayInputStream uploadPackV2Setup(
 			Consumer<UploadPack> postConstructionSetup, String... inputLines)
 			throws Exception {
 
 		ByteArrayInputStream send = linesAsInputStream(inputLines);
 
 		server.getConfig().setString("protocol", null, "version", "2");
 		UploadPack up = new UploadPack(server);
 		if (postConstructionSetup != null) {
 			postConstructionSetup.accept(up);
 		}
 		up.setExtraParameters(Sets.of("version=2"));
 
 		ByteArrayOutputStream recv = new ByteArrayOutputStream();
 		up.upload(send, recv, null);
 		stats = up.getStatistics();
 
 		return new ByteArrayInputStream(recv.toByteArray());
 	}
 
 	private static ByteArrayInputStream linesAsInputStream(String... inputLines)
 			throws IOException {
 		try (ByteArrayOutputStream send = new ByteArrayOutputStream()) {
 			PacketLineOut pckOut = new PacketLineOut(send);
 			for (String line : inputLines) {
 				Objects.requireNonNull(line);
 				if (PacketLineIn.isEnd(line)) {
 					pckOut.end();
 				} else if (PacketLineIn.isDelimiter(line)) {
 					pckOut.writeDelim();
 				} else {
 					pckOut.writeString(line);
 				}
 			}
 			return new ByteArrayInputStream(send.toByteArray());
 		}
 	}
 
 	/*
 	 * Invokes UploadPack with protocol v2 and sends it the given lines.
 	 * Returns UploadPack's output stream, not including the capability
 	 * advertisement by the server.
 	 */
 	private ByteArrayInputStream uploadPackV2(
 			Consumer<UploadPack> postConstructionSetup,
 			String... inputLines)
 			throws Exception {
 		ByteArrayInputStream recvStream =
 				uploadPackV2Setup(postConstructionSetup, inputLines);
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		// drain capabilities
 		while (!PacketLineIn.isEnd(pckIn.readString())) {
 			// do nothing
 		}
 		return recvStream;
 	}
 
 	private ByteArrayInputStream uploadPackV2(String... inputLines) throws Exception {
 		return uploadPackV2(null, inputLines);
 	}
 
 	private static class TestV2Hook implements ProtocolV2Hook {
 		private CapabilitiesV2Request capabilitiesRequest;
 
 		private LsRefsV2Request lsRefsRequest;
 
 		private FetchV2Request fetchRequest;
 
 		@Override
 		public void onCapabilities(CapabilitiesV2Request req) {
 			capabilitiesRequest = req;
 		}
 
 		@Override
 		public void onLsRefs(LsRefsV2Request req) {
 			lsRefsRequest = req;
 		}
 
 		@Override
 		public void onFetch(FetchV2Request req) {
 			fetchRequest = req;
 		}
 	}
 
 	@Test
 	public void testV2Capabilities() throws Exception {
 		TestV2Hook hook = new TestV2Hook();
 		ByteArrayInputStream recvStream = uploadPackV2Setup(
 				(UploadPack up) -> {up.setProtocolV2Hook(hook);},
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(hook.capabilitiesRequest, notNullValue());
 		assertThat(pckIn.readString(), is("version 2"));
 		assertThat(
 				Arrays.asList(pckIn.readString(), pckIn.readString(),
 						pckIn.readString()),
 				// TODO(jonathantanmy) This check is written this way
 				// to make it simple to see that we expect this list of
 				// capabilities, but probably should be loosened to
 				// allow additional commands to be added to the list,
 				// and additional capabilities to be added to existing
 				// commands without requiring test changes.
 				hasItems("ls-refs", "fetch=shallow", "server-option"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	private void checkAdvertisedIfAllowed(String configSection, String configName,
 			String fetchCapability) throws Exception {
 		server.getConfig().setBoolean(configSection, null, configName, true);
 		ByteArrayInputStream recvStream =
 				uploadPackV2Setup(null, PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("version 2"));
 
 		ArrayList<String> lines = new ArrayList<>();
 		String line;
 		while (!PacketLineIn.isEnd((line = pckIn.readString()))) {
 			if (line.startsWith("fetch=")) {
 				assertThat(
 					Arrays.asList(line.substring(6).split(" ")),
 					containsInAnyOrder(fetchCapability, "shallow"));
 				lines.add("fetch");
 			} else {
 				lines.add(line);
 			}
 		}
 		assertThat(lines, containsInAnyOrder("ls-refs", "fetch", "server-option"));
 	}
 
 	private void checkUnadvertisedIfUnallowed(String configSection,
 			String configName, String fetchCapability) throws Exception {
 		server.getConfig().setBoolean(configSection, null, configName, false);
 		ByteArrayInputStream recvStream =
 				uploadPackV2Setup(null, PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("version 2"));
 
 		ArrayList<String> lines = new ArrayList<>();
 		String line;
 		while (!PacketLineIn.isEnd((line = pckIn.readString()))) {
 			if (line.startsWith("fetch=")) {
 				List<String> fetchItems = Arrays.asList(line.substring(6).split(" "));
 				assertThat(fetchItems, hasItems("shallow"));
 				assertFalse(fetchItems.contains(fetchCapability));
 				lines.add("fetch");
 			} else {
 				lines.add(line);
 			}
 		}
 		assertThat(lines, hasItems("ls-refs", "fetch", "server-option"));
 	}
 
 	@Test
 	public void testV2CapabilitiesAllowFilter() throws Exception {
 		checkAdvertisedIfAllowed("uploadpack", "allowfilter", "filter");
 		checkUnadvertisedIfUnallowed("uploadpack", "allowfilter", "filter");
 	}
 
 	@Test
 	public void testV2CapabilitiesRefInWant() throws Exception {
 		checkAdvertisedIfAllowed("uploadpack", "allowrefinwant", "ref-in-want");
 	}
 
 	@Test
 	public void testV2CapabilitiesRefInWantNotAdvertisedIfUnallowed() throws Exception {
 		checkUnadvertisedIfUnallowed("uploadpack", "allowrefinwant",
 				"ref-in-want");
 	}
 
 	@Test
 	public void testV2CapabilitiesAdvertiseSidebandAll() throws Exception {
 		server.getConfig().setBoolean("uploadpack", null, "allowsidebandall",
 				true);
 		checkAdvertisedIfAllowed("uploadpack", "advertisesidebandall",
 				"sideband-all");
 		checkUnadvertisedIfUnallowed("uploadpack", "advertisesidebandall",
 				"sideband-all");
 	}
 
 	@Test
 	public void testV2CapabilitiesRefInWantNotAdvertisedIfAdvertisingForbidden() throws Exception {
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant", true);
 		server.getConfig().setBoolean("uploadpack", null, "advertiserefinwant", false);
 		ByteArrayInputStream recvStream =
 				uploadPackV2Setup(null, PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("version 2"));
 		assertThat(
 				Arrays.asList(pckIn.readString(), pckIn.readString(),
 						pckIn.readString()),
 				hasItems("ls-refs", "fetch=shallow", "server-option"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2EmptyRequest() throws Exception {
 		ByteArrayInputStream recvStream = uploadPackV2(PacketLineIn.end());
 		// Verify that there is nothing more after the capability
 		// advertisement.
 		assertEquals(0, recvStream.available());
 	}
 
 	@Test
 	public void testV2LsRefs() throws Exception {
 		RevCommit tip = remote.commit().message("message").create();
 		remote.update("master", tip);
 		server.updateRef("HEAD").link("refs/heads/master");
 		RevTag tag = remote.tag("tag", tip);
 		remote.update("refs/tags/tag", tag);
 
 		TestV2Hook hook = new TestV2Hook();
 		ByteArrayInputStream recvStream = uploadPackV2(
 				(UploadPack up) -> {up.setProtocolV2Hook(hook);},
 				"command=ls-refs\n", PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(hook.lsRefsRequest, notNullValue());
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tag.toObjectId().getName() + " refs/tags/tag"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2LsRefsSymrefs() throws Exception {
 		RevCommit tip = remote.commit().message("message").create();
 		remote.update("master", tip);
 		server.updateRef("HEAD").link("refs/heads/master");
 		RevTag tag = remote.tag("tag", tip);
 		remote.update("refs/tags/tag", tag);
 
 		ByteArrayInputStream recvStream = uploadPackV2("command=ls-refs\n",
 				PacketLineIn.delimiter(), "symrefs", PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD symref-target:refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tag.toObjectId().getName() + " refs/tags/tag"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2LsRefsPeel() throws Exception {
 		RevCommit tip = remote.commit().message("message").create();
 		remote.update("master", tip);
 		server.updateRef("HEAD").link("refs/heads/master");
 		RevTag tag = remote.tag("tag", tip);
 		remote.update("refs/tags/tag", tag);
 
 		ByteArrayInputStream recvStream = uploadPackV2("command=ls-refs\n",
 				PacketLineIn.delimiter(), "peel", PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(
 			pckIn.readString(),
 			is(tag.toObjectId().getName() + " refs/tags/tag peeled:"
 				+ tip.toObjectId().getName()));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2LsRefsMultipleCommands() throws Exception {
 		RevCommit tip = remote.commit().message("message").create();
 		remote.update("master", tip);
 		server.updateRef("HEAD").link("refs/heads/master");
 		RevTag tag = remote.tag("tag", tip);
 		remote.update("refs/tags/tag", tag);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 				"command=ls-refs\n", PacketLineIn.delimiter(), "symrefs",
 				"peel", PacketLineIn.end(), "command=ls-refs\n",
 				PacketLineIn.delimiter(), PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD symref-target:refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(
 			pckIn.readString(),
 			is(tag.toObjectId().getName() + " refs/tags/tag peeled:"
 				+ tip.toObjectId().getName()));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " HEAD"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tag.toObjectId().getName() + " refs/tags/tag"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2LsRefsRefPrefix() throws Exception {
 		RevCommit tip = remote.commit().message("message").create();
 		remote.update("master", tip);
 		remote.update("other", tip);
 		remote.update("yetAnother", tip);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=ls-refs\n",
 			PacketLineIn.delimiter(),
 			"ref-prefix refs/heads/maste",
 			"ref-prefix refs/heads/other",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/other"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2LsRefsRefPrefixNoSlash() throws Exception {
 		RevCommit tip = remote.commit().message("message").create();
 		remote.update("master", tip);
 		remote.update("other", tip);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=ls-refs\n",
 			PacketLineIn.delimiter(),
 			"ref-prefix refs/heads/maste",
 			"ref-prefix r",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/master"));
 		assertThat(pckIn.readString(), is(tip.toObjectId().getName() + " refs/heads/other"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2LsRefsUnrecognizedArgument() throws Exception {
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2("command=ls-refs\n",
 						PacketLineIn.delimiter(), "invalid-argument\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("unexpected invalid-argument"));
 	}
 
 	@Test
 	public void testV2LsRefsServerOptions() throws Exception {
 		String[] lines = { "command=ls-refs\n",
 				"server-option=one\n", "server-option=two\n",
 				PacketLineIn.delimiter(),
 				PacketLineIn.end() };
 
 		TestV2Hook testHook = new TestV2Hook();
 		uploadPackV2Setup((UploadPack up) -> {up.setProtocolV2Hook(testHook);}, lines);
 
 		LsRefsV2Request req = testHook.lsRefsRequest;
 		assertEquals(2, req.getServerOptions().size());
 		assertThat(req.getServerOptions(), hasItems("one", "two"));
 	}
 
 	/*
 	 * Parse multiplexed packfile output from upload-pack using protocol V2
 	 * into the client repository.
 	 */
 	private ReceivedPackStatistics parsePack(ByteArrayInputStream recvStream) throws Exception {
 		return parsePack(recvStream, NullProgressMonitor.INSTANCE);
 	}
 
 	private ReceivedPackStatistics parsePack(ByteArrayInputStream recvStream, ProgressMonitor pm)
 			throws Exception {
 		SideBandInputStream sb = new SideBandInputStream(
 				recvStream, pm,
 				new StringWriter(), NullOutputStream.INSTANCE);
 		PackParser pp = client.newObjectInserter().newPackParser(sb);
 		pp.parse(NullProgressMonitor.INSTANCE);
 
 		// Ensure that there is nothing left in the stream.
 		assertEquals(-1, recvStream.read());
 
 		return pp.getReceivedPackStatistics();
 	}
 
 	@Test
 	public void testV2FetchRequestPolicyAdvertised() throws Exception {
 		RevCommit advertized = remote.commit().message("x").create();
 		RevCommit unadvertized = remote.commit().message("y").create();
 		remote.update("branch1", advertized);
 
 		// This works
 		uploadPackV2(
 			(UploadPack up) -> {up.setRequestPolicy(RequestPolicy.ADVERTISED);},
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + advertized.name() + "\n",
 			PacketLineIn.end());
 
 		// This doesn't
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2(
 						(UploadPack up) -> {up.setRequestPolicy(RequestPolicy.ADVERTISED);},
 						"command=fetch\n", PacketLineIn.delimiter(),
 						"want " + unadvertized.name() + "\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("want " + unadvertized.name() + " not valid"));
 	}
 
 	@Test
 	public void testV2FetchRequestPolicyReachableCommit() throws Exception {
 		RevCommit reachable = remote.commit().message("x").create();
 		RevCommit advertized = remote.commit().message("x").parent(reachable)
 				.create();
 		RevCommit unreachable = remote.commit().message("y").create();
 		remote.update("branch1", advertized);
 
 		// This works
 		uploadPackV2(
 			(UploadPack up) -> {up.setRequestPolicy(RequestPolicy.REACHABLE_COMMIT);},
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + reachable.name() + "\n",
 				PacketLineIn.end());
 
 		// This doesn't
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2(
 						(UploadPack up) -> {up.setRequestPolicy(RequestPolicy.REACHABLE_COMMIT);},
 						"command=fetch\n", PacketLineIn.delimiter(),
 						"want " + unreachable.name() + "\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("want " + unreachable.name() + " not valid"));
 	}
 
 	@Test
 	public void testV2FetchRequestPolicyTip() throws Exception {
 		RevCommit parentOfTip = remote.commit().message("x").create();
 		RevCommit tip = remote.commit().message("y").parent(parentOfTip)
 				.create();
 		remote.update("secret", tip);
 
 		// This works
 		uploadPackV2(
 			(UploadPack up) -> {
 				up.setRequestPolicy(RequestPolicy.TIP);
 				up.setRefFilter(new RejectAllRefFilter());
 			},
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + tip.name() + "\n",
 				PacketLineIn.end());
 
 		// This doesn't
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2(
 						(UploadPack up) -> {
 							up.setRequestPolicy(RequestPolicy.TIP);
 							up.setRefFilter(new RejectAllRefFilter());
 						},
 						"command=fetch\n", PacketLineIn.delimiter(),
 						"want " + parentOfTip.name() + "\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("want " + parentOfTip.name() + " not valid"));
 	}
 
 	@Test
 	public void testV2FetchRequestPolicyReachableCommitTip() throws Exception {
 		RevCommit parentOfTip = remote.commit().message("x").create();
 		RevCommit tip = remote.commit().message("y").parent(parentOfTip)
 				.create();
 		RevCommit unreachable = remote.commit().message("y").create();
 		remote.update("secret", tip);
 
 		// This works
 		uploadPackV2(
 				(UploadPack up) -> {
 					up.setRequestPolicy(RequestPolicy.REACHABLE_COMMIT_TIP);
 					up.setRefFilter(new RejectAllRefFilter());
 				},
 				"command=fetch\n",
 				PacketLineIn.delimiter(), "want " + parentOfTip.name() + "\n",
 				PacketLineIn.end());
 
 		// This doesn't
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2(
 						(UploadPack up) -> {
 							up.setRequestPolicy(RequestPolicy.REACHABLE_COMMIT_TIP);
 							up.setRefFilter(new RejectAllRefFilter());
 						},
 						"command=fetch\n",
 						PacketLineIn.delimiter(),
 						"want " + unreachable.name() + "\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("want " + unreachable.name() + " not valid"));
 	}
 
 	@Test
 	public void testV2FetchRequestPolicyAny() throws Exception {
 		RevCommit unreachable = remote.commit().message("y").create();
 
 		// Exercise to make sure that even unreachable commits can be fetched
 		uploadPackV2(
 			(UploadPack up) -> {up.setRequestPolicy(RequestPolicy.ANY);},
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + unreachable.name() + "\n",
 				PacketLineIn.end());
 	}
 
 	@Test
 	public void testV2FetchServerDoesNotStopNegotiation() throws Exception {
 		RevCommit fooParent = remote.commit().message("x").create();
 		RevCommit fooChild = remote.commit().message("x").parent(fooParent).create();
 		RevCommit barParent = remote.commit().message("y").create();
 		RevCommit barChild = remote.commit().message("y").parent(barParent).create();
 		remote.update("branch1", fooChild);
 		remote.update("branch2", barChild);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + fooChild.toObjectId().getName() + "\n",
 			"want " + barChild.toObjectId().getName() + "\n",
 			"have " + fooParent.toObjectId().getName() + "\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("acknowledgments"));
 		assertThat(pckIn.readString(), is("ACK " + fooParent.toObjectId().getName()));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2FetchServerStopsNegotiation() throws Exception {
 		RevCommit fooParent = remote.commit().message("x").create();
 		RevCommit fooChild = remote.commit().message("x").parent(fooParent).create();
 		RevCommit barParent = remote.commit().message("y").create();
 		RevCommit barChild = remote.commit().message("y").parent(barParent).create();
 		remote.update("branch1", fooChild);
 		remote.update("branch2", barChild);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + fooChild.toObjectId().getName() + "\n",
 			"want " + barChild.toObjectId().getName() + "\n",
 			"have " + fooParent.toObjectId().getName() + "\n",
 			"have " + barParent.toObjectId().getName() + "\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("acknowledgments"));
 		assertThat(
 			Arrays.asList(pckIn.readString(), pckIn.readString()),
 			hasItems(
 				"ACK " + fooParent.toObjectId().getName(),
 				"ACK " + barParent.toObjectId().getName()));
 		assertThat(pckIn.readString(), is("ready"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(fooParent.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(fooChild.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(barParent.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(barChild.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchClientStopsNegotiation() throws Exception {
 		RevCommit fooParent = remote.commit().message("x").create();
 		RevCommit fooChild = remote.commit().message("x").parent(fooParent).create();
 		RevCommit barParent = remote.commit().message("y").create();
 		RevCommit barChild = remote.commit().message("y").parent(barParent).create();
 		remote.update("branch1", fooChild);
 		remote.update("branch2", barChild);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + fooChild.toObjectId().getName() + "\n",
 			"want " + barChild.toObjectId().getName() + "\n",
 			"have " + fooParent.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(fooParent.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(fooChild.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(barParent.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(barChild.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchThinPack() throws Exception {
 		String commonInBlob = "abcdefghijklmnopqrstuvwxyz";
 
 		RevBlob parentBlob = remote.blob(commonInBlob + "a");
 		RevCommit parent = remote
 				.commit(remote.tree(remote.file("foo", parentBlob)));
 		RevBlob childBlob = remote.blob(commonInBlob + "b");
 		RevCommit child = remote
 				.commit(remote.tree(remote.file("foo", childBlob)), parent);
 		remote.update("branch1", child);
 
 		// Pretend that we have parent to get a thin pack based on it.
 		ByteArrayInputStream recvStream = uploadPackV2("command=fetch\n",
 				PacketLineIn.delimiter(),
 				"want " + child.toObjectId().getName() + "\n",
 				"have " + parent.toObjectId().getName() + "\n", "thin-pack\n",
 				"done\n", PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("packfile"));
 
 		// Verify that we received a thin pack by trying to apply it
 		// against the client repo, which does not have parent.
 		IOException e = assertThrows(IOException.class,
 				() -> parsePack(recvStream));
 		assertThat(e.getMessage(),
 				containsString("pack has unresolved deltas"));
 	}
 
 	@Test
 	public void testV2FetchNoProgress() throws Exception {
 		RevCommit commit = remote.commit().message("x").create();
 		remote.update("branch1", commit);
 
 		// Without no-progress, progress is reported.
 		StringWriter sw = new StringWriter();
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + commit.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream, new TextProgressMonitor(sw));
 		assertFalse(sw.toString().isEmpty());
 
 		// With no-progress, progress is not reported.
 		sw = new StringWriter();
 		recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + commit.toObjectId().getName() + "\n",
 			"no-progress\n",
 			"done\n",
 				PacketLineIn.end());
 		pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream, new TextProgressMonitor(sw));
 		assertTrue(sw.toString().isEmpty());
 	}
 
 	@Test
 	public void testV2FetchIncludeTag() throws Exception {
 		RevCommit commit = remote.commit().message("x").create();
 		RevTag tag = remote.tag("tag", commit);
 		remote.update("branch1", commit);
 		remote.update("refs/tags/tag", tag);
 
 		// Without include-tag.
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + commit.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(tag.toObjectId()));
 
 		// With tag.
 		recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + commit.toObjectId().getName() + "\n",
 			"include-tag\n",
 			"done\n",
 				PacketLineIn.end());
 		pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(tag.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchOfsDelta() throws Exception {
 		String commonInBlob = "abcdefghijklmnopqrstuvwxyz";
 
 		RevBlob parentBlob = remote.blob(commonInBlob + "a");
 		RevCommit parent = remote.commit(remote.tree(remote.file("foo", parentBlob)));
 		RevBlob childBlob = remote.blob(commonInBlob + "b");
 		RevCommit child = remote.commit(remote.tree(remote.file("foo", childBlob)), parent);
 		remote.update("branch1", child);
 
 		// Without ofs-delta.
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + child.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		ReceivedPackStatistics receivedStats = parsePack(recvStream);
 		assertTrue(receivedStats.getNumOfsDelta() == 0);
 
 		// With ofs-delta.
 		recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + child.toObjectId().getName() + "\n",
 			"ofs-delta\n",
 			"done\n",
 				PacketLineIn.end());
 		pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		receivedStats = parsePack(recvStream);
 		assertTrue(receivedStats.getNumOfsDelta() != 0);
 	}
 
 	@Test
 	public void testV2FetchShallow() throws Exception {
 		RevCommit commonParent = remote.commit().message("parent").create();
 		RevCommit fooChild = remote.commit().message("x").parent(commonParent).create();
 		RevCommit barChild = remote.commit().message("y").parent(commonParent).create();
 		remote.update("branch1", barChild);
 
 		// Without shallow, the server thinks that we have
 		// commonParent, so it doesn't send it.
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + barChild.toObjectId().getName() + "\n",
 			"have " + fooChild.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(barChild.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(commonParent.toObjectId()));
 
 		// With shallow, the server knows that we don't have
 		// commonParent, so it sends it.
 		recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + barChild.toObjectId().getName() + "\n",
 			"have " + fooChild.toObjectId().getName() + "\n",
 			"shallow " + fooChild.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(commonParent.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchDeepenAndDone() throws Exception {
 		RevCommit parent = remote.commit().message("parent").create();
 		RevCommit child = remote.commit().message("x").parent(parent).create();
 		remote.update("branch1", child);
 
 		// "deepen 1" sends only the child.
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + child.toObjectId().getName() + "\n",
 			"deepen 1\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(), is("shallow " + child.toObjectId().getName()));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(child.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(parent.toObjectId()));
 
 		// Without that, the parent is sent too.
 		recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + child.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(parent.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchDeepenWithoutDone() throws Exception {
 		RevCommit parent = remote.commit().message("parent").create();
 		RevCommit child = remote.commit().message("x").parent(parent).create();
 		remote.update("branch1", child);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + child.toObjectId().getName() + "\n",
 			"deepen 1\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		// Verify that only the correct section is sent. "shallow-info"
 		// is not sent because, according to the specification, it is
 		// sent only if a packfile is sent.
 		assertThat(pckIn.readString(), is("acknowledgments"));
 		assertThat(pckIn.readString(), is("NAK"));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2FetchShallowSince() throws Exception {
 		PersonIdent person = new PersonIdent(remote.getRepository());
 
 		RevCommit beyondBoundary = remote.commit()
 			.committer(new PersonIdent(person, 1510000000, 0)).create();
 		RevCommit boundary = remote.commit().parent(beyondBoundary)
 			.committer(new PersonIdent(person, 1520000000, 0)).create();
 		RevCommit tooOld = remote.commit()
 			.committer(new PersonIdent(person, 1500000000, 0)).create();
 		RevCommit merge = remote.commit().parent(boundary).parent(tooOld)
 			.committer(new PersonIdent(person, 1530000000, 0)).create();
 
 		remote.update("branch1", merge);
 
 		// Report that we only have "boundary" as a shallow boundary.
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"shallow " + boundary.toObjectId().getName() + "\n",
 			"deepen-since 1510000\n",
 			"want " + merge.toObjectId().getName() + "\n",
 			"have " + boundary.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 
 		// "merge" is shallow because one of its parents is committed
 		// earlier than the given deepen-since time.
 		assertThat(pckIn.readString(), is("shallow " + merge.toObjectId().getName()));
 
 		// "boundary" is unshallow because its parent committed at or
 		// later than the given deepen-since time.
 		assertThat(pckIn.readString(), is("unshallow " + boundary.toObjectId().getName()));
 
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		// The server does not send this because it is committed
 		// earlier than the given deepen-since time.
 		assertFalse(client.getObjectDatabase().has(tooOld.toObjectId()));
 
 		// The server does not send this because the client claims to
 		// have it.
 		assertFalse(client.getObjectDatabase().has(boundary.toObjectId()));
 
 		// The server sends both these commits.
 		assertTrue(client.getObjectDatabase().has(beyondBoundary.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(merge.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchShallowSince_excludedParentWithMultipleChildren() throws Exception {
 		PersonIdent person = new PersonIdent(remote.getRepository());
 
 		RevCommit base = remote.commit()
 			.committer(new PersonIdent(person, 1500000000, 0)).create();
 		RevCommit child1 = remote.commit().parent(base)
 			.committer(new PersonIdent(person, 1510000000, 0)).create();
 		RevCommit child2 = remote.commit().parent(base)
 			.committer(new PersonIdent(person, 1520000000, 0)).create();
 
 		remote.update("branch1", child1);
 		remote.update("branch2", child2);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"deepen-since 1510000\n",
 			"want " + child1.toObjectId().getName() + "\n",
 			"want " + child2.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 
 		// "base" is excluded, so its children are shallow.
 		assertThat(
 			Arrays.asList(pckIn.readString(), pckIn.readString()),
 			hasItems(
 				"shallow " + child1.toObjectId().getName(),
 				"shallow " + child2.toObjectId().getName()));
 
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		// Only the children are sent.
 		assertFalse(client.getObjectDatabase().has(base.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(child1.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(child2.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchShallowSince_noCommitsSelected() throws Exception {
 		PersonIdent person = new PersonIdent(remote.getRepository());
 
 		RevCommit tooOld = remote.commit()
 				.committer(new PersonIdent(person, 1500000000, 0)).create();
 
 		remote.update("branch1", tooOld);
 
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2("command=fetch\n", PacketLineIn.delimiter(),
 						"deepen-since 1510000\n",
 						"want " + tooOld.toObjectId().getName() + "\n",
 						"done\n", PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("No commits selected for shallow request"));
 	}
 
 	@Test
 	public void testV2FetchDeepenNot() throws Exception {
 		RevCommit one = remote.commit().message("one").create();
 		RevCommit two = remote.commit().message("two").parent(one).create();
 		RevCommit three = remote.commit().message("three").parent(two).create();
 		RevCommit side = remote.commit().message("side").parent(one).create();
 		RevCommit merge = remote.commit().message("merge")
 			.parent(three).parent(side).create();
 
 		remote.update("branch1", merge);
 		remote.update("side", side);
 
 		// The client is a shallow clone that only has "three", and
 		// wants "merge" while excluding "side".
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"shallow " + three.toObjectId().getName() + "\n",
 			"deepen-not side\n",
 			"want " + merge.toObjectId().getName() + "\n",
 			"have " + three.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 
 		// "merge" is shallow because "side" is excluded by deepen-not.
 		// "two" is shallow because "one" (as parent of "side") is excluded by deepen-not.
 		assertThat(
 			Arrays.asList(pckIn.readString(), pckIn.readString()),
 			hasItems(
 				"shallow " + merge.toObjectId().getName(),
 				"shallow " + two.toObjectId().getName()));
 
 		// "three" is unshallow because its parent "two" is now available.
 		assertThat(pckIn.readString(), is("unshallow " + three.toObjectId().getName()));
 
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		// The server does not send these because they are excluded by
 		// deepen-not.
 		assertFalse(client.getObjectDatabase().has(side.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(one.toObjectId()));
 
 		// The server does not send this because the client claims to
 		// have it.
 		assertFalse(client.getObjectDatabase().has(three.toObjectId()));
 
 		// The server sends both these commits.
 		assertTrue(client.getObjectDatabase().has(merge.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(two.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchDeepenNot_excludeDescendantOfWant()
 			throws Exception {
 		RevCommit one = remote.commit().message("one").create();
 		RevCommit two = remote.commit().message("two").parent(one).create();
 		RevCommit three = remote.commit().message("three").parent(two).create();
 		RevCommit four = remote.commit().message("four").parent(three).create();
 
 		remote.update("two", two);
 		remote.update("four", four);
 
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2("command=fetch\n", PacketLineIn.delimiter(),
 						"deepen-not four\n",
 						"want " + two.toObjectId().getName() + "\n", "done\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("No commits selected for shallow request"));
 	}
 
 	@Test
 	public void testV2FetchDeepenNot_supportAnnotatedTags() throws Exception {
 		RevCommit one = remote.commit().message("one").create();
 		RevCommit two = remote.commit().message("two").parent(one).create();
 		RevCommit three = remote.commit().message("three").parent(two).create();
 		RevCommit four = remote.commit().message("four").parent(three).create();
 		RevTag twoTag = remote.tag("twotag", two);
 
 		remote.update("refs/tags/twotag", twoTag);
 		remote.update("four", four);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"deepen-not twotag\n",
 			"want " + four.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(), is("shallow " + three.toObjectId().getName()));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(one.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(two.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(three.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(four.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchDeepenNot_excludedParentWithMultipleChildren() throws Exception {
 		PersonIdent person = new PersonIdent(remote.getRepository());
 
 		RevCommit base = remote.commit()
 			.committer(new PersonIdent(person, 1500000000, 0)).create();
 		RevCommit child1 = remote.commit().parent(base)
 			.committer(new PersonIdent(person, 1510000000, 0)).create();
 		RevCommit child2 = remote.commit().parent(base)
 			.committer(new PersonIdent(person, 1520000000, 0)).create();
 
 		remote.update("base", base);
 		remote.update("branch1", child1);
 		remote.update("branch2", child2);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"deepen-not base\n",
 			"want " + child1.toObjectId().getName() + "\n",
 			"want " + child2.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("shallow-info"));
 
 		// "base" is excluded, so its children are shallow.
 		assertThat(
 			Arrays.asList(pckIn.readString(), pckIn.readString()),
 			hasItems(
 				"shallow " + child1.toObjectId().getName(),
 				"shallow " + child2.toObjectId().getName()));
 
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		// Only the children are sent.
 		assertFalse(client.getObjectDatabase().has(base.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(child1.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(child2.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchUnrecognizedArgument() throws Exception {
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2("command=fetch\n", PacketLineIn.delimiter(),
 						"invalid-argument\n", PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("unexpected invalid-argument"));
 	}
 
 	@Test
 	public void testV2FetchServerOptions() throws Exception {
 		String[] lines = { "command=fetch\n", "server-option=one\n",
 				"server-option=two\n", PacketLineIn.delimiter(),
 				PacketLineIn.end() };
 
 		TestV2Hook testHook = new TestV2Hook();
 		uploadPackV2Setup((UploadPack up) -> {up.setProtocolV2Hook(testHook);}, lines);
 
 		FetchV2Request req = testHook.fetchRequest;
 		assertNotNull(req);
 		assertEquals(2, req.getServerOptions().size());
 		assertThat(req.getServerOptions(), hasItems("one", "two"));
 	}
 
 	@Test
 	public void testV2FetchFilter() throws Exception {
 		RevBlob big = remote.blob("foobar");
 		RevBlob small = remote.blob("fooba");
 		RevTree tree = remote.tree(remote.file("1", big),
 				remote.file("2", small));
 		RevCommit commit = remote.commit(tree);
 		remote.update("master", commit);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowfilter", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + commit.toObjectId().getName() + "\n",
 			"filter blob:limit=5\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		assertFalse(client.getObjectDatabase().has(big.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(small.toObjectId()));
 	}
 
 	abstract class TreeBuilder {
 		abstract void addElements(DirCacheBuilder dcBuilder) throws Exception;
 
 		RevTree build() throws Exception {
 			DirCache dc = DirCache.newInCore();
 			DirCacheBuilder dcBuilder = dc.builder();
 			addElements(dcBuilder);
 			dcBuilder.finish();
 			ObjectId id;
 			try (ObjectInserter ins =
 					remote.getRepository().newObjectInserter()) {
 				id = dc.writeTree(ins);
 				ins.flush();
 			}
 			return remote.getRevWalk().parseTree(id);
 		}
 	}
 
 	class DeepTreePreparator {
 		RevBlob blobLowDepth = remote.blob("lo");
 		RevBlob blobHighDepth = remote.blob("hi");
 
 		RevTree subtree = remote.tree(remote.file("1", blobHighDepth));
 		RevTree rootTree = (new TreeBuilder() {
 				@Override
 				void addElements(DirCacheBuilder dcBuilder) throws Exception {
 					dcBuilder.add(remote.file("1", blobLowDepth));
 					dcBuilder.addTree(new byte[] {'2'}, DirCacheEntry.STAGE_0,
 							remote.getRevWalk().getObjectReader(), subtree);
 				}
 			}).build();
 		RevCommit commit = remote.commit(rootTree);
 
 		DeepTreePreparator() throws Exception {}
 	}
 
 	private void uploadV2WithTreeDepthFilter(
 			long depth, ObjectId... wants) throws Exception {
 		server.getConfig().setBoolean("uploadpack", null, "allowfilter", true);
 
 		List<String> input = new ArrayList<>();
 		input.add("command=fetch\n");
 		input.add(PacketLineIn.delimiter());
 		for (ObjectId want : wants) {
 			input.add("want " + want.getName() + "\n");
 		}
 		input.add("filter tree:" + depth + "\n");
 		input.add("done\n");
 		input.add(PacketLineIn.end());
 		ByteArrayInputStream recvStream =
 				uploadPackV2(
 						(UploadPack up) -> {up.setRequestPolicy(RequestPolicy.ANY);},
 						input.toArray(new String[0]));
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 	}
 
 	@Test
 	public void testV2FetchFilterTreeDepth0() throws Exception {
 		DeepTreePreparator preparator = new DeepTreePreparator();
 		remote.update("master", preparator.commit);
 
 		uploadV2WithTreeDepthFilter(0, preparator.commit.toObjectId());
 
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.rootTree.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.subtree.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.blobLowDepth.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.blobHighDepth.toObjectId()));
 		assertEquals(1, stats.getTreesTraversed());
 	}
 
 	@Test
 	public void testV2FetchFilterTreeDepth1_serverHasBitmap() throws Exception {
 		DeepTreePreparator preparator = new DeepTreePreparator();
 		remote.update("master", preparator.commit);
 
 		// The bitmap should be ignored since we need to track the depth while
 		// traversing the trees.
 		generateBitmaps(server);
 
 		uploadV2WithTreeDepthFilter(1, preparator.commit.toObjectId());
 
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.rootTree.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.subtree.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.blobLowDepth.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.blobHighDepth.toObjectId()));
 		assertEquals(1, stats.getTreesTraversed());
 	}
 
 	@Test
 	public void testV2FetchFilterTreeDepth2() throws Exception {
 		DeepTreePreparator preparator = new DeepTreePreparator();
 		remote.update("master", preparator.commit);
 
 		uploadV2WithTreeDepthFilter(2, preparator.commit.toObjectId());
 
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.rootTree.toObjectId()));
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.subtree.toObjectId()));
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.blobLowDepth.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.blobHighDepth.toObjectId()));
 		assertEquals(2, stats.getTreesTraversed());
 	}
 
 	/**
 	 * Creates a commit with the following files:
 	 * <pre>
 	 * a/x/b/foo
 	 * x/b/foo
 	 * </pre>
 	 * which has an identical tree in two locations: once at / and once at /a
 	 */
 	class RepeatedSubtreePreparator {
 		RevBlob foo = remote.blob("foo");
 		RevTree subtree3 = remote.tree(remote.file("foo", foo));
 		RevTree subtree2 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'b'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree3);
 			}
 		}).build();
 		RevTree subtree1 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'x'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree2);
 			}
 		}).build();
 		RevTree rootTree = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'a'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree1);
 				dcBuilder.addTree(new byte[] {'x'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree2);
 			}
 		}).build();
 		RevCommit commit = remote.commit(rootTree);
 
 		RepeatedSubtreePreparator() throws Exception {}
 	}
 
 	@Test
 	public void testV2FetchFilterTreeDepth_iterateOverTreeAtTwoLevels()
 			throws Exception {
 		// Test tree:<depth> where a tree is iterated to twice - once where a
 		// subentry is too deep to be included, and again where the blob inside
 		// it is shallow enough to be included.
 		RepeatedSubtreePreparator preparator = new RepeatedSubtreePreparator();
 		remote.update("master", preparator.commit);
 
 		uploadV2WithTreeDepthFilter(4, preparator.commit.toObjectId());
 
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.foo.toObjectId()));
 	}
 
 	/**
 	 * Creates a commit with the following files:
 	 * <pre>
 	 * a/x/b/foo
 	 * b/u/c/baz
 	 * y/x/b/foo
 	 * z/v/c/baz
 	 * </pre>
 	 * which has two pairs of identical trees:
 	 * <ul>
 	 * <li>one at /a and /y
 	 * <li>one at /b/u and /z/v
 	 * </ul>
 	 * Note that this class defines unique 8 trees (rootTree and subtree1-7)
 	 * which means PackStatistics should report having visited 8 trees.
 	 */
 	class RepeatedSubtreeAtSameLevelPreparator {
 		RevBlob foo = remote.blob("foo");
 
 		/** foo */
 		RevTree subtree1 = remote.tree(remote.file("foo", foo));
 
 		/** b/foo */
 		RevTree subtree2 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'b'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree1);
 			}
 		}).build();
 
 		/** x/b/foo */
 		RevTree subtree3 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'x'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree2);
 			}
 		}).build();
 
 		RevBlob baz = remote.blob("baz");
 
 		/** baz */
 		RevTree subtree4 = remote.tree(remote.file("baz", baz));
 
 		/** c/baz */
 		RevTree subtree5 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'c'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree4);
 			}
 		}).build();
 
 		/** u/c/baz */
 		RevTree subtree6 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'u'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree5);
 			}
 		}).build();
 
 		/** v/c/baz */
 		RevTree subtree7 = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'v'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree5);
 			}
 		}).build();
 
 		RevTree rootTree = (new TreeBuilder() {
 			@Override
 			void addElements(DirCacheBuilder dcBuilder) throws Exception {
 				dcBuilder.addTree(new byte[] {'a'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree3);
 				dcBuilder.addTree(new byte[] {'b'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree6);
 				dcBuilder.addTree(new byte[] {'y'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree3);
 				dcBuilder.addTree(new byte[] {'z'}, DirCacheEntry.STAGE_0,
 						remote.getRevWalk().getObjectReader(), subtree7);
 			}
 		}).build();
 		RevCommit commit = remote.commit(rootTree);
 
 		RepeatedSubtreeAtSameLevelPreparator() throws Exception {}
 	}
 
 	@Test
 	public void testV2FetchFilterTreeDepth_repeatTreeAtSameLevelIncludeFile()
 			throws Exception {
 		RepeatedSubtreeAtSameLevelPreparator preparator =
 				new RepeatedSubtreeAtSameLevelPreparator();
 		remote.update("master", preparator.commit);
 
 		uploadV2WithTreeDepthFilter(5, preparator.commit.toObjectId());
 
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.foo.toObjectId()));
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.baz.toObjectId()));
 		assertEquals(8, stats.getTreesTraversed());
 	}
 
 	@Test
 	public void testV2FetchFilterTreeDepth_repeatTreeAtSameLevelExcludeFile()
 			throws Exception {
 		RepeatedSubtreeAtSameLevelPreparator preparator =
 				new RepeatedSubtreeAtSameLevelPreparator();
 		remote.update("master", preparator.commit);
 
 		uploadV2WithTreeDepthFilter(4, preparator.commit.toObjectId());
 
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.foo.toObjectId()));
 		assertFalse(client.getObjectDatabase()
 				.has(preparator.baz.toObjectId()));
 		assertEquals(8, stats.getTreesTraversed());
 	}
 
 	@Test
 	public void testWantFilteredObject() throws Exception {
 		RepeatedSubtreePreparator preparator = new RepeatedSubtreePreparator();
 		remote.update("master", preparator.commit);
 
 		// Specify wanted blob objects that are deep enough to be filtered. We
 		// should still upload them.
 		uploadV2WithTreeDepthFilter(
 				3,
 				preparator.commit.toObjectId(),
 				preparator.foo.toObjectId());
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.foo.toObjectId()));
 
 		client = newRepo("client");
 		// Specify a wanted tree object that is deep enough to be filtered. We
 		// should still upload it.
 		uploadV2WithTreeDepthFilter(
 				2,
 				preparator.commit.toObjectId(),
 				preparator.subtree3.toObjectId());
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.foo.toObjectId()));
 		assertTrue(client.getObjectDatabase()
 				.has(preparator.subtree3.toObjectId()));
 	}
 
 	private void checkV2FetchWhenNotAllowed(String fetchLine, String expectedMessage)
 			throws Exception {
 		RevCommit commit = remote.commit().message("0").create();
 		remote.update("master", commit);
 
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2("command=fetch\n", PacketLineIn.delimiter(),
 						"want " + commit.toObjectId().getName() + "\n",
 						fetchLine, "done\n", PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString(expectedMessage));
 	}
 
 	@Test
 	public void testV2FetchFilterWhenNotAllowed() throws Exception {
 		checkV2FetchWhenNotAllowed(
 			"filter blob:limit=5\n",
 			"unexpected filter blob:limit=5");
 	}
 
 	@Test
 	public void testV2FetchWantRefIfNotAllowed() throws Exception {
 		checkV2FetchWhenNotAllowed(
 			"want-ref refs/heads/one\n",
 			"unexpected want-ref refs/heads/one");
 	}
 
 	@Test
 	public void testV2FetchSidebandAllIfNotAllowed() throws Exception {
 		checkV2FetchWhenNotAllowed(
 			"sideband-all\n",
 			"unexpected sideband-all");
 	}
 
 	@Test
 	public void testV2FetchWantRef() throws Exception {
 		RevCommit one = remote.commit().message("1").create();
 		RevCommit two = remote.commit().message("2").create();
 		RevCommit three = remote.commit().message("3").create();
 		remote.update("one", one);
 		remote.update("two", two);
 		remote.update("three", three);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want-ref refs/heads/one\n",
 			"want-ref refs/heads/two\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(
 				Arrays.asList(pckIn.readString(), pckIn.readString()),
 				hasItems(
 					one.toObjectId().getName() + " refs/heads/one",
 					two.toObjectId().getName() + " refs/heads/two"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		assertTrue(client.getObjectDatabase().has(one.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(two.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(three.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchBadWantRef() throws Exception {
 		RevCommit one = remote.commit().message("1").create();
 		remote.update("one", one);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant",
 				true);
 
 		UploadPackInternalServerErrorException e = assertThrows(
 				UploadPackInternalServerErrorException.class,
 				() -> uploadPackV2("command=fetch\n", PacketLineIn.delimiter(),
 						"want-ref refs/heads/one\n",
 						"want-ref refs/heads/nonExistentRef\n", "done\n",
 						PacketLineIn.end()));
 		assertThat(e.getCause().getMessage(),
 				containsString("Invalid ref name: refs/heads/nonExistentRef"));
 	}
 
 	@Test
 	public void testV2FetchMixedWantRef() throws Exception {
 		RevCommit one = remote.commit().message("1").create();
 		RevCommit two = remote.commit().message("2").create();
 		RevCommit three = remote.commit().message("3").create();
 		remote.update("one", one);
 		remote.update("two", two);
 		remote.update("three", three);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want-ref refs/heads/one\n",
 			"want " + two.toObjectId().getName() + "\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(
 				pckIn.readString(),
 				is(one.toObjectId().getName() + " refs/heads/one"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		assertTrue(client.getObjectDatabase().has(one.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(two.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(three.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchWantRefWeAlreadyHave() throws Exception {
 		RevCommit one = remote.commit().message("1").create();
 		remote.update("one", one);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want-ref refs/heads/one\n",
 			"have " + one.toObjectId().getName(),
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		// The client still needs to know the hash of the object that
 		// refs/heads/one points to, even though it already has the
 		// object ...
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(
 				pckIn.readString(),
 				is(one.toObjectId().getName() + " refs/heads/one"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 
 		// ... but the client does not need the object itself.
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertFalse(client.getObjectDatabase().has(one.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchWantRefAndDeepen() throws Exception {
 		RevCommit parent = remote.commit().message("parent").create();
 		RevCommit child = remote.commit().message("x").parent(parent).create();
 		remote.update("branch1", child);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want-ref refs/heads/branch1\n",
 			"deepen 1\n",
 			"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		// shallow-info appears first, then wanted-refs.
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(), is("shallow " + child.toObjectId().getName()));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(pckIn.readString(), is(child.toObjectId().getName() + " refs/heads/branch1"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(child.toObjectId()));
 		assertFalse(client.getObjectDatabase().has(parent.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchMissingShallow() throws Exception {
 		RevCommit one = remote.commit().message("1").create();
 		RevCommit two = remote.commit().message("2").parent(one).create();
 		RevCommit three = remote.commit().message("3").parent(two).create();
 		remote.update("three", three);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant",
 				true);
 
 		ByteArrayInputStream recvStream = uploadPackV2("command=fetch\n",
 				PacketLineIn.delimiter(),
 				"want-ref refs/heads/three\n",
 				"deepen 3",
 				"shallow 0123012301230123012301230123012301230123",
 				"shallow " + two.getName() + '\n',
 				"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("shallow-info"));
 		assertThat(pckIn.readString(),
 				is("shallow " + one.toObjectId().getName()));
 		assertThat(pckIn.readString(),
 				is("unshallow " + two.toObjectId().getName()));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(pckIn.readString(),
 				is(three.toObjectId().getName() + " refs/heads/three"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 
 		assertTrue(client.getObjectDatabase().has(one.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(two.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(three.toObjectId()));
 	}
 
 	@Test
 	public void testV2FetchSidebandAllNoPackfile() throws Exception {
 		RevCommit fooParent = remote.commit().message("x").create();
 		RevCommit fooChild = remote.commit().message("x").parent(fooParent).create();
 		RevCommit barParent = remote.commit().message("y").create();
 		RevCommit barChild = remote.commit().message("y").parent(barParent).create();
 		remote.update("branch1", fooChild);
 		remote.update("branch2", barChild);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowsidebandall", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"sideband-all\n",
 			"want " + fooChild.toObjectId().getName() + "\n",
 			"want " + barChild.toObjectId().getName() + "\n",
 			"have " + fooParent.toObjectId().getName() + "\n",
 			PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		assertThat(pckIn.readString(), is("\001acknowledgments"));
 		assertThat(pckIn.readString(), is("\001ACK " + fooParent.getName()));
 		assertTrue(PacketLineIn.isEnd(pckIn.readString()));
 	}
 
 	@Test
 	public void testV2FetchSidebandAllPackfile() throws Exception {
 		RevCommit commit = remote.commit().message("x").create();
 		remote.update("master", commit);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowsidebandall", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2("command=fetch\n",
 				PacketLineIn.delimiter(),
 				"want " + commit.getName() + "\n",
 				"sideband-all\n",
 				"done\n",
 				PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		String s;
 		// When sideband-all is used, object counting happens before
 		// "packfile" is written, and object counting outputs progress
 		// in sideband 2. Skip all these lines.
 		for (s = pckIn.readString(); s.startsWith("\002"); s = pckIn.readString()) {
 			// do nothing
 		}
 		assertThat(s, is("\001packfile"));
 		parsePack(recvStream);
 	}
 
 	@Test
 	public void testV2FetchPackfileUris() throws Exception {
 		// Inside the pack
 		RevCommit commit = remote.commit().message("x").create();
 		remote.update("master", commit);
 		generateBitmaps(server);
 
 		// Outside the pack
 		RevCommit commit2 = remote.commit().message("x").parent(commit).create();
 		remote.update("master", commit2);
 
 		server.getConfig().setBoolean("uploadpack", null, "allowsidebandall", true);
 
 		ByteArrayInputStream recvStream = uploadPackV2(
 			(UploadPack up) -> {
 				up.setCachedPackUriProvider(new CachedPackUriProvider() {
 					@Override
 					public PackInfo getInfo(CachedPack pack,
 							Collection<String> protocolsSupported)
 							throws IOException {
 						assertThat(protocolsSupported, hasItems("https"));
 						if (!protocolsSupported.contains("https"))
 							return null;
 						return new PackInfo("myhash", "myuri", 100);
 					}
 
 				});
 			},
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want " + commit2.getName() + "\n",
 			"sideband-all\n",
 			"packfile-uris https\n",
 			"done\n",
 			PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 
 		String s;
 		// skip all \002 strings
 		for (s = pckIn.readString(); s.startsWith("\002"); s = pckIn.readString()) {
 			// do nothing
 		}
 		assertThat(s, is("\001packfile-uris"));
 		assertThat(pckIn.readString(), is("\001myhash myuri"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("\001packfile"));
 		parsePack(recvStream);
 
 		assertFalse(client.getObjectDatabase().has(commit.toObjectId()));
 		assertTrue(client.getObjectDatabase().has(commit2.toObjectId()));
 	}
 
 	@Test
 	public void testGetPeerAgentProtocolV0() throws Exception {
 		RevCommit one = remote.commit().message("1").create();
 		remote.update("one", one);
 
 		UploadPack up = new UploadPack(server);
 		ByteArrayInputStream send = linesAsInputStream(
 				"want " + one.getName() + " agent=JGit-test/1.2.3\n",
 				PacketLineIn.end(),
 				"have 11cedf1b796d44207da702f7d420684022fc0f09\n", "done\n");
 
 		ByteArrayOutputStream recv = new ByteArrayOutputStream();
 		up.upload(send, recv, null);
 
 		assertEquals(up.getPeerUserAgent(), "JGit-test/1.2.3");
 	}
 
 	@Test
 	public void testGetPeerAgentProtocolV2() throws Exception {
 		server.getConfig().setString("protocol", null, "version", "2");
 
 		RevCommit one = remote.commit().message("1").create();
 		remote.update("one", one);
 
 		UploadPack up = new UploadPack(server);
 		up.setExtraParameters(Sets.of("version=2"));
 
 		ByteArrayInputStream send = linesAsInputStream(
 				"command=fetch\n", "agent=JGit-test/1.2.4\n",
 				PacketLineIn.delimiter(), "want " + one.getName() + "\n",
 				"have 11cedf1b796d44207da702f7d420684022fc0f09\n", "done\n",
 				PacketLineIn.end());
 
 		ByteArrayOutputStream recv = new ByteArrayOutputStream();
 		up.upload(send, recv, null);
 
 		assertEquals(up.getPeerUserAgent(), "JGit-test/1.2.4");
 	}
 
 	private static class RejectAllRefFilter implements RefFilter {
 		@Override
 		public Map<String, Ref> filter(Map<String, Ref> refs) {
 			return new HashMap<>();
 		}
 	}
 
 	@Test
 	public void testSingleBranchCloneTagChain() throws Exception {
 		RevBlob blob0 = remote.blob("Initial content of first file");
 		RevBlob blob1 = remote.blob("Second file content");
 		RevCommit commit0 = remote
 				.commit(remote.tree(remote.file("prvni.txt", blob0)));
 		RevCommit commit1 = remote
 				.commit(remote.tree(remote.file("druhy.txt", blob1)), commit0);
 		remote.update("master", commit1);
 
 		RevTag heavyTag1 = remote.tag("commitTagRing", commit0);
 		remote.getRevWalk().parseHeaders(heavyTag1);
 		RevTag heavyTag2 = remote.tag("middleTagRing", heavyTag1);
 		remote.lightweightTag("refTagRing", heavyTag2);
 
 		UploadPack uploadPack = new UploadPack(remote.getRepository());
 
 		ByteArrayOutputStream cli = new ByteArrayOutputStream();
 		PacketLineOut clientWant = new PacketLineOut(cli);
 		clientWant.writeString("want " + commit1.name()
 				+ " multi_ack_detailed include-tag thin-pack ofs-delta agent=tempo/pflaska");
 		clientWant.end();
 		clientWant.writeString("done\n");
 
 		try (ByteArrayOutputStream serverResponse = new ByteArrayOutputStream()) {
 
 			uploadPack.setPreUploadHook(new PreUploadHook() {
 				@Override
 				public void onBeginNegotiateRound(UploadPack up,
 						Collection<? extends ObjectId> wants, int cntOffered)
 						throws ServiceMayNotContinueException {
 					// Do nothing.
 				}
 
 				@Override
 				public void onEndNegotiateRound(UploadPack up,
 						Collection<? extends ObjectId> wants, int cntCommon,
 						int cntNotFound, boolean ready)
 						throws ServiceMayNotContinueException {
 					// Do nothing.
 				}
 
 				@Override
 				public void onSendPack(UploadPack up,
 						Collection<? extends ObjectId> wants,
 						Collection<? extends ObjectId> haves)
 						throws ServiceMayNotContinueException {
 					// collect pack data
 					serverResponse.reset();
 				}
 			});
 			uploadPack.upload(new ByteArrayInputStream(cli.toByteArray()),
 					serverResponse, System.err);
 			InputStream packReceived = new ByteArrayInputStream(
 					serverResponse.toByteArray());
 			PackLock lock = null;
 			try (ObjectInserter ins = client.newObjectInserter()) {
 				PackParser parser = ins.newPackParser(packReceived);
 				parser.setAllowThin(true);
 				parser.setLockMessage("receive-tag-chain");
 				ProgressMonitor mlc = NullProgressMonitor.INSTANCE;
 				lock = parser.parse(mlc, mlc);
 				ins.flush();
 			} finally {
 				if (lock != null) {
 					lock.unlock();
 				}
 			}
 			InMemoryRepository.MemObjDatabase objDb = client
 					.getObjectDatabase();
 			assertTrue(objDb.has(blob0.toObjectId()));
 			assertTrue(objDb.has(blob1.toObjectId()));
 			assertTrue(objDb.has(commit0.toObjectId()));
 			assertTrue(objDb.has(commit1.toObjectId()));
 			assertTrue(objDb.has(heavyTag1.toObjectId()));
 			assertTrue(objDb.has(heavyTag2.toObjectId()));
 		}
 	}
 
 	@Test
 	public void testSafeToClearRefsInFetchV0() throws Exception {
 		server =
 			new RefCallsCountingRepository(
 				new DfsRepositoryDescription("server"));
 		remote = new TestRepository<>(server);
 		RevCommit one = remote.commit().message("1").create();
 		remote.update("one", one);
 		testProtocol = new TestProtocol<>((Object req, Repository db) -> {
 			UploadPack up = new UploadPack(db);
 			return up;
 		}, null);
 		uri = testProtocol.register(ctx, server);
 		try (Transport tn = testProtocol.open(uri, client, "server")) {
 			tn.fetch(NullProgressMonitor.INSTANCE,
 				Collections.singletonList(new RefSpec(one.name())));
 		}
 		assertTrue(client.getObjectDatabase().has(one.toObjectId()));
 		assertEquals(1, ((RefCallsCountingRepository)server).numRefCalls());
 	}
 
 	@Test
 	public void testSafeToClearRefsInFetchV2() throws Exception {
 		server =
 			new RefCallsCountingRepository(
 				new DfsRepositoryDescription("server"));
 		remote = new TestRepository<>(server);
 		RevCommit one = remote.commit().message("1").create();
 		RevCommit two = remote.commit().message("2").create();
 		remote.update("one", one);
 		remote.update("two", two);
 		server.getConfig().setBoolean("uploadpack", null, "allowrefinwant", true);
 		ByteArrayInputStream recvStream = uploadPackV2(
 			"command=fetch\n",
 			PacketLineIn.delimiter(),
 			"want-ref refs/heads/one\n",
 			"want-ref refs/heads/two\n",
 			"done\n",
 			PacketLineIn.end());
 		PacketLineIn pckIn = new PacketLineIn(recvStream);
 		assertThat(pckIn.readString(), is("wanted-refs"));
 		assertThat(
 			Arrays.asList(pckIn.readString(), pckIn.readString()),
 			hasItems(
 				one.toObjectId().getName() + " refs/heads/one",
 				two.toObjectId().getName() + " refs/heads/two"));
 		assertTrue(PacketLineIn.isDelimiter(pckIn.readString()));
 		assertThat(pckIn.readString(), is("packfile"));
 		parsePack(recvStream);
 		assertTrue(client.getObjectDatabase().has(one.toObjectId()));
 		assertEquals(1, ((RefCallsCountingRepository)server).numRefCalls());
 	}
 
 	private class RefCallsCountingRepository extends InMemoryRepository {
 		private final InMemoryRepository.MemRefDatabase refdb;
 		private int numRefCalls;
 
 		public RefCallsCountingRepository(DfsRepositoryDescription repoDesc) {
 			super(repoDesc);
 			refdb = new InMemoryRepository.MemRefDatabase() {
 				@Override
 				public List<Ref> getRefs() throws IOException {
 					numRefCalls++;
 					return super.getRefs();
 				}
 			};
 		}
 
 		public int numRefCalls() {
 			return numRefCalls;
 		}
 
 		@Override
 		public RefDatabase getRefDatabase() {
 			return refdb;
 		}
 	}
 }