org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcBasicPackingTest.java - sop/jgit - Git at Google

 /*
  * Copyright (C) 2012, Christian Halstrick <christian.halstrick@sap.com>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
  * under the terms of the Eclipse Distribution License v1.0 which
  * accompanies this distribution, is reproduced below, and is
  * available at http://www.eclipse.org/org/documents/edl-v10.php
  *
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or
  * without modification, are permitted provided that the following
  * conditions are met:
  *
  * - Redistributions of source code must retain the above copyright
  *   notice, this list of conditions and the following disclaimer.
  *
  * - Redistributions in binary form must reproduce the above
  *   copyright notice, this list of conditions and the following
  *   disclaimer in the documentation and/or other materials provided
  *   with the distribution.
  *
  * - Neither the name of the Eclipse Foundation, Inc. nor the
  *   names of its contributors may be used to endorse or promote
  *   products derived from this software without specific prior
  *   written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 package org.eclipse.jgit.internal.storage.file;

 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;

 import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Date;
 import java.util.List;

 import org.eclipse.jgit.junit.TestRepository.BranchBuilder;
 import org.eclipse.jgit.lib.ConfigConstants;
 import org.eclipse.jgit.lib.RefUpdate;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.storage.file.FileBasedConfig;
 import org.eclipse.jgit.storage.pack.PackConfig;
 import org.junit.Test;
 import org.junit.experimental.theories.DataPoints;
 import org.junit.experimental.theories.Theories;
 import org.junit.experimental.theories.Theory;
 import org.junit.runner.RunWith;

 @RunWith(Theories.class)
 public class GcBasicPackingTest extends GcTestCase {
 	@DataPoints
 	public static boolean[] aggressiveValues = { true, false };

 	@Theory
 	public void repackEmptyRepo_noPackCreated(boolean aggressive)
 			throws IOException {
 		configureGc(gc, aggressive);
 		gc.repack();
 		assertEquals(0, repo.getObjectDatabase().getPacks().size());
 	}

 	@Theory
 	public void testPackRepoWithNoRefs(boolean aggressive) throws Exception {
 		tr.commit().add("A", "A").add("B", "B").create();
 		stats = gc.getStatistics();
 		assertEquals(4, stats.numberOfLooseObjects);
 		assertEquals(0, stats.numberOfPackedObjects);
 		configureGc(gc, aggressive);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(4, stats.numberOfLooseObjects);
 		assertEquals(0, stats.numberOfPackedObjects);
 		assertEquals(0, stats.numberOfPackFiles);
 		assertEquals(0, stats.numberOfBitmaps);
 	}

 	@Theory
 	public void testPack2Commits(boolean aggressive) throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		bb.commit().add("A", "A").add("B", "B").create();
 		bb.commit().add("A", "A2").add("B", "B2").create();

 		stats = gc.getStatistics();
 		assertEquals(8, stats.numberOfLooseObjects);
 		assertEquals(0, stats.numberOfPackedObjects);
 		configureGc(gc, aggressive);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		assertEquals(8, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
 		assertEquals(2, stats.numberOfBitmaps);
 	}

 	@Theory
 	public void testPackAllObjectsInOnePack(boolean aggressive)
 			throws Exception {
 		tr.branch("refs/heads/master").commit().add("A", "A").add("B", "B")
 				.create();
 		stats = gc.getStatistics();
 		assertEquals(4, stats.numberOfLooseObjects);
 		assertEquals(0, stats.numberOfPackedObjects);
 		configureGc(gc, aggressive);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		assertEquals(4, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
 		assertEquals(1, stats.numberOfBitmaps);

 		// Do the gc again and check that it hasn't changed anything
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		assertEquals(4, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
 		assertEquals(1, stats.numberOfBitmaps);
 	}

 	@Theory
 	public void testPackCommitsAndLooseOne(boolean aggressive)
 			throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		RevCommit first = bb.commit().add("A", "A").add("B", "B").create();
 		bb.commit().add("A", "A2").add("B", "B2").create();
 		tr.update("refs/heads/master", first);

 		stats = gc.getStatistics();
 		assertEquals(8, stats.numberOfLooseObjects);
 		assertEquals(0, stats.numberOfPackedObjects);
 		configureGc(gc, aggressive);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		assertEquals(8, stats.numberOfPackedObjects);
 		assertEquals(2, stats.numberOfPackFiles);
 		assertEquals(1, stats.numberOfBitmaps);
 	}

 	@Theory
 	public void testNotPackTwice(boolean aggressive) throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		RevCommit first = bb.commit().message("M").add("M", "M").create();
 		bb.commit().message("B").add("B", "Q").create();
 		bb.commit().message("A").add("A", "A").create();
 		RevCommit second = tr.commit().parent(first).message("R").add("R", "Q")
 				.create();
 		tr.update("refs/tags/t1", second);

 		Collection<PackFile> oldPacks = tr.getRepository().getObjectDatabase()
 				.getPacks();
 		assertEquals(0, oldPacks.size());
 		stats = gc.getStatistics();
 		assertEquals(11, stats.numberOfLooseObjects);
 		assertEquals(0, stats.numberOfPackedObjects);

 		gc.setExpireAgeMillis(0);
 		fsTick();
 		configureGc(gc, aggressive);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);

 		List<PackFile> packs = new ArrayList<>(
 				repo.getObjectDatabase().getPacks());
 		assertEquals(11, packs.get(0).getObjectCount());
 	}

 	@Test
 	public void testDonePruneTooYoungPacks() throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		bb.commit().message("M").add("M", "M").create();

 		String tempRef = "refs/heads/soon-to-be-unreferenced";
 		BranchBuilder bb2 = tr.branch(tempRef);
 		bb2.commit().message("M").add("M", "M").create();

 		gc.setExpireAgeMillis(0);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		assertEquals(4, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
 		File oldPackfile = tr.getRepository().getObjectDatabase().getPacks()
 				.iterator().next().getPackFile();

 		fsTick();

 		// delete the temp ref, orphaning its commit
 		RefUpdate update = tr.getRepository().getRefDatabase().newUpdate(tempRef, false);
 		update.setForceUpdate(true);
 		update.delete();

 		bb.commit().message("B").add("B", "Q").create();

 		// The old packfile is too young to be deleted. We should end up with
 		// two pack files
 		gc.setExpire(new Date(oldPackfile.lastModified() - 1));
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		// if objects exist in multiple packFiles then they are counted multiple
 		// times
 		assertEquals(10, stats.numberOfPackedObjects);
 		assertEquals(2, stats.numberOfPackFiles);

 		// repack again but now without a grace period for loose objects. Since
 		// we don't have loose objects anymore this shouldn't change anything
 		gc.setExpireAgeMillis(0);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		// if objects exist in multiple packFiles then they are counted multiple
 		// times
 		assertEquals(10, stats.numberOfPackedObjects);
 		assertEquals(2, stats.numberOfPackFiles);

 		// repack again but now without a grace period for packfiles. We should
 		// end up with one packfile
 		gc.setPackExpireAgeMillis(0);

 		// we want to keep newly-loosened objects though
 		gc.setExpireAgeMillis(-1);

 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(1, stats.numberOfLooseObjects);
 		// if objects exist in multiple packFiles then they are counted multiple
 		// times
 		assertEquals(6, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
 	}

 	@Test
 	public void testImmediatePruning() throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		bb.commit().message("M").add("M", "M").create();

 		String tempRef = "refs/heads/soon-to-be-unreferenced";
 		BranchBuilder bb2 = tr.branch(tempRef);
 		bb2.commit().message("M").add("M", "M").create();

 		gc.setExpireAgeMillis(0);
 		gc.gc();
 		stats = gc.getStatistics();

 		fsTick();

 		// delete the temp ref, orphaning its commit
 		RefUpdate update = tr.getRepository().getRefDatabase().newUpdate(tempRef, false);
 		update.setForceUpdate(true);
 		update.delete();

 		bb.commit().message("B").add("B", "Q").create();

 		// We want to immediately prune deleted objects
 		FileBasedConfig config = repo.getConfig();
 		config.setString(ConfigConstants.CONFIG_GC_SECTION, null,
 			ConfigConstants.CONFIG_KEY_PRUNEEXPIRE, "now");
 		config.save();

 		//And we don't want to keep packs full of dead objects
 		gc.setPackExpireAgeMillis(0);

 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
 		assertEquals(6, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
 	}

 	@Test
 	public void testPreserveAndPruneOldPacks() throws Exception {
 		testPreserveOldPacks();
 		configureGc(gc, false).setPrunePreserved(true);
 		gc.gc();

 		assertFalse(repo.getObjectDatabase().getPreservedDirectory().exists());
 	}

 	private void testPreserveOldPacks() throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		bb.commit().message("P").add("P", "P").create();

 		// pack loose object into packfile
 		gc.setExpireAgeMillis(0);
 		gc.gc();
 		File oldPackfile = tr.getRepository().getObjectDatabase().getPacks()
 				.iterator().next().getPackFile();
 		assertTrue(oldPackfile.exists());

 		fsTick();
 		bb.commit().message("B").add("B", "Q").create();

 		// repack again but now without a grace period for packfiles. We should
 		// end up with a new packfile and the old one should be placed in the
 		// preserved directory
 		gc.setPackExpireAgeMillis(0);
 		configureGc(gc, false).setPreserveOldPacks(true);
 		gc.gc();

 		File oldPackDir = repo.getObjectDatabase().getPreservedDirectory();
 		String oldPackFileName = oldPackfile.getName();
 		String oldPackName = oldPackFileName.substring(0,
 				oldPackFileName.lastIndexOf('.')) + ".old-pack";  //$NON-NLS-1$
 		File preservePackFile = new File(oldPackDir, oldPackName);
 		assertTrue(preservePackFile.exists());
 	}

 	private PackConfig configureGc(GC myGc, boolean aggressive) {
 		PackConfig pconfig = new PackConfig(repo);
 		if (aggressive) {
 			pconfig.setDeltaSearchWindowSize(250);
 			pconfig.setMaxDeltaDepth(250);
 			pconfig.setReuseObjects(false);
 		} else
 			pconfig = new PackConfig(repo);
 		myGc.setPackConfig(pconfig);
 		return pconfig;
 	}
 }
	/*
	* Copyright (C) 2012, Christian Halstrick <christian.halstrick@sap.com>
	* and other copyright owners as documented in the project's IP log.
	*
	* This program and the accompanying materials are made available
	* under the terms of the Eclipse Distribution License v1.0 which
	* accompanies this distribution, is reproduced below, and is
	* available at http://www.eclipse.org/org/documents/edl-v10.php
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials provided
	* with the distribution.
	*
	* - Neither the name of the Eclipse Foundation, Inc. nor the
	* names of its contributors may be used to endorse or promote
	* products derived from this software without specific prior
	* written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
	* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
	* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
	* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	package org.eclipse.jgit.internal.storage.file;

	import static org.junit.Assert.assertEquals;
	import static org.junit.Assert.assertFalse;
	import static org.junit.Assert.assertTrue;

	import java.io.File;
	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.Collection;
	import java.util.Date;
	import java.util.List;

	import org.eclipse.jgit.junit.TestRepository.BranchBuilder;
	import org.eclipse.jgit.lib.ConfigConstants;
	import org.eclipse.jgit.lib.RefUpdate;
	import org.eclipse.jgit.revwalk.RevCommit;
	import org.eclipse.jgit.storage.file.FileBasedConfig;
	import org.eclipse.jgit.storage.pack.PackConfig;
	import org.junit.Test;
	import org.junit.experimental.theories.DataPoints;
	import org.junit.experimental.theories.Theories;
	import org.junit.experimental.theories.Theory;
	import org.junit.runner.RunWith;

	@RunWith(Theories.class)
	public class GcBasicPackingTest extends GcTestCase {
	@DataPoints
	public static boolean[] aggressiveValues = { true, false };

	@Theory
	public void repackEmptyRepo_noPackCreated(boolean aggressive)
	throws IOException {
	configureGc(gc, aggressive);
	gc.repack();
	assertEquals(0, repo.getObjectDatabase().getPacks().size());
	}

	@Theory
	public void testPackRepoWithNoRefs(boolean aggressive) throws Exception {
	tr.commit().add("A", "A").add("B", "B").create();
	stats = gc.getStatistics();
	assertEquals(4, stats.numberOfLooseObjects);
	assertEquals(0, stats.numberOfPackedObjects);
	configureGc(gc, aggressive);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(4, stats.numberOfLooseObjects);
	assertEquals(0, stats.numberOfPackedObjects);
	assertEquals(0, stats.numberOfPackFiles);
	assertEquals(0, stats.numberOfBitmaps);
	}

	@Theory
	public void testPack2Commits(boolean aggressive) throws Exception {
	BranchBuilder bb = tr.branch("refs/heads/master");
	bb.commit().add("A", "A").add("B", "B").create();
	bb.commit().add("A", "A2").add("B", "B2").create();

	stats = gc.getStatistics();
	assertEquals(8, stats.numberOfLooseObjects);
	assertEquals(0, stats.numberOfPackedObjects);
	configureGc(gc, aggressive);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	assertEquals(8, stats.numberOfPackedObjects);
	assertEquals(1, stats.numberOfPackFiles);
	assertEquals(2, stats.numberOfBitmaps);
	}

	@Theory
	public void testPackAllObjectsInOnePack(boolean aggressive)
	throws Exception {
	tr.branch("refs/heads/master").commit().add("A", "A").add("B", "B")
	.create();
	stats = gc.getStatistics();
	assertEquals(4, stats.numberOfLooseObjects);
	assertEquals(0, stats.numberOfPackedObjects);
	configureGc(gc, aggressive);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	assertEquals(4, stats.numberOfPackedObjects);
	assertEquals(1, stats.numberOfPackFiles);
	assertEquals(1, stats.numberOfBitmaps);

	// Do the gc again and check that it hasn't changed anything
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	assertEquals(4, stats.numberOfPackedObjects);
	assertEquals(1, stats.numberOfPackFiles);
	assertEquals(1, stats.numberOfBitmaps);
	}

	@Theory
	public void testPackCommitsAndLooseOne(boolean aggressive)
	throws Exception {
	BranchBuilder bb = tr.branch("refs/heads/master");
	RevCommit first = bb.commit().add("A", "A").add("B", "B").create();
	bb.commit().add("A", "A2").add("B", "B2").create();
	tr.update("refs/heads/master", first);

	stats = gc.getStatistics();
	assertEquals(8, stats.numberOfLooseObjects);
	assertEquals(0, stats.numberOfPackedObjects);
	configureGc(gc, aggressive);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	assertEquals(8, stats.numberOfPackedObjects);
	assertEquals(2, stats.numberOfPackFiles);
	assertEquals(1, stats.numberOfBitmaps);
	}

	@Theory
	public void testNotPackTwice(boolean aggressive) throws Exception {
	BranchBuilder bb = tr.branch("refs/heads/master");
	RevCommit first = bb.commit().message("M").add("M", "M").create();
	bb.commit().message("B").add("B", "Q").create();
	bb.commit().message("A").add("A", "A").create();
	RevCommit second = tr.commit().parent(first).message("R").add("R", "Q")
	.create();
	tr.update("refs/tags/t1", second);

	Collection<PackFile> oldPacks = tr.getRepository().getObjectDatabase()
	.getPacks();
	assertEquals(0, oldPacks.size());
	stats = gc.getStatistics();
	assertEquals(11, stats.numberOfLooseObjects);
	assertEquals(0, stats.numberOfPackedObjects);

	gc.setExpireAgeMillis(0);
	fsTick();
	configureGc(gc, aggressive);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);

	List<PackFile> packs = new ArrayList<>(
	repo.getObjectDatabase().getPacks());
	assertEquals(11, packs.get(0).getObjectCount());
	}

	@Test
	public void testDonePruneTooYoungPacks() throws Exception {
	BranchBuilder bb = tr.branch("refs/heads/master");
	bb.commit().message("M").add("M", "M").create();

	String tempRef = "refs/heads/soon-to-be-unreferenced";
	BranchBuilder bb2 = tr.branch(tempRef);
	bb2.commit().message("M").add("M", "M").create();

	gc.setExpireAgeMillis(0);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	assertEquals(4, stats.numberOfPackedObjects);
	assertEquals(1, stats.numberOfPackFiles);
	File oldPackfile = tr.getRepository().getObjectDatabase().getPacks()
	.iterator().next().getPackFile();

	fsTick();

	// delete the temp ref, orphaning its commit
	RefUpdate update = tr.getRepository().getRefDatabase().newUpdate(tempRef, false);
	update.setForceUpdate(true);
	update.delete();

	bb.commit().message("B").add("B", "Q").create();

	// The old packfile is too young to be deleted. We should end up with
	// two pack files
	gc.setExpire(new Date(oldPackfile.lastModified() - 1));
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	// if objects exist in multiple packFiles then they are counted multiple
	// times
	assertEquals(10, stats.numberOfPackedObjects);
	assertEquals(2, stats.numberOfPackFiles);

	// repack again but now without a grace period for loose objects. Since
	// we don't have loose objects anymore this shouldn't change anything
	gc.setExpireAgeMillis(0);
	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	// if objects exist in multiple packFiles then they are counted multiple
	// times
	assertEquals(10, stats.numberOfPackedObjects);
	assertEquals(2, stats.numberOfPackFiles);

	// repack again but now without a grace period for packfiles. We should
	// end up with one packfile
	gc.setPackExpireAgeMillis(0);

	// we want to keep newly-loosened objects though
	gc.setExpireAgeMillis(-1);

	gc.gc();
	stats = gc.getStatistics();
	assertEquals(1, stats.numberOfLooseObjects);
	// if objects exist in multiple packFiles then they are counted multiple
	// times
	assertEquals(6, stats.numberOfPackedObjects);
	assertEquals(1, stats.numberOfPackFiles);
	}

	@Test
	public void testImmediatePruning() throws Exception {
	BranchBuilder bb = tr.branch("refs/heads/master");
	bb.commit().message("M").add("M", "M").create();

	String tempRef = "refs/heads/soon-to-be-unreferenced";
	BranchBuilder bb2 = tr.branch(tempRef);
	bb2.commit().message("M").add("M", "M").create();

	gc.setExpireAgeMillis(0);
	gc.gc();
	stats = gc.getStatistics();

	fsTick();

	// delete the temp ref, orphaning its commit
	RefUpdate update = tr.getRepository().getRefDatabase().newUpdate(tempRef, false);
	update.setForceUpdate(true);
	update.delete();

	bb.commit().message("B").add("B", "Q").create();

	// We want to immediately prune deleted objects
	FileBasedConfig config = repo.getConfig();
	config.setString(ConfigConstants.CONFIG_GC_SECTION, null,
	ConfigConstants.CONFIG_KEY_PRUNEEXPIRE, "now");
	config.save();

	//And we don't want to keep packs full of dead objects
	gc.setPackExpireAgeMillis(0);

	gc.gc();
	stats = gc.getStatistics();
	assertEquals(0, stats.numberOfLooseObjects);
	assertEquals(6, stats.numberOfPackedObjects);
	assertEquals(1, stats.numberOfPackFiles);
	}

	@Test
	public void testPreserveAndPruneOldPacks() throws Exception {
	testPreserveOldPacks();
	configureGc(gc, false).setPrunePreserved(true);
	gc.gc();

	assertFalse(repo.getObjectDatabase().getPreservedDirectory().exists());
	}

	private void testPreserveOldPacks() throws Exception {
	BranchBuilder bb = tr.branch("refs/heads/master");
	bb.commit().message("P").add("P", "P").create();

	// pack loose object into packfile
	gc.setExpireAgeMillis(0);
	gc.gc();
	File oldPackfile = tr.getRepository().getObjectDatabase().getPacks()
	.iterator().next().getPackFile();
	assertTrue(oldPackfile.exists());

	fsTick();
	bb.commit().message("B").add("B", "Q").create();

	// repack again but now without a grace period for packfiles. We should
	// end up with a new packfile and the old one should be placed in the
	// preserved directory
	gc.setPackExpireAgeMillis(0);
	configureGc(gc, false).setPreserveOldPacks(true);
	gc.gc();

	File oldPackDir = repo.getObjectDatabase().getPreservedDirectory();
	String oldPackFileName = oldPackfile.getName();
	String oldPackName = oldPackFileName.substring(0,
	oldPackFileName.lastIndexOf('.')) + ".old-pack"; //$NON-NLS-1$
	File preservePackFile = new File(oldPackDir, oldPackName);
	assertTrue(preservePackFile.exists());
	}

	private PackConfig configureGc(GC myGc, boolean aggressive) {
	PackConfig pconfig = new PackConfig(repo);
	if (aggressive) {
	pconfig.setDeltaSearchWindowSize(250);
	pconfig.setMaxDeltaDepth(250);
	pconfig.setReuseObjects(false);
	} else
	pconfig = new PackConfig(repo);
	myGc.setPackConfig(pconfig);
	return pconfig;
	}
	}