org.eclipse.jgit.test/tst/org/eclipse/jgit/api/DescribeCommandTest.java - jgit - Git at Google

 /*
  * Copyright (C) 2013, CloudBees, Inc.
  * 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.api;

 import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;

 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.util.Arrays;
 import java.util.Collection;

 import org.eclipse.jgit.api.errors.GitAPIException;
 import org.eclipse.jgit.api.errors.RefNotFoundException;
 import org.eclipse.jgit.junit.RepositoryTestCase;
 import org.eclipse.jgit.lib.ObjectId;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 import org.junit.runners.Parameterized.Parameter;
 import org.junit.runners.Parameterized.Parameters;

 @RunWith(Parameterized.class)
 public class DescribeCommandTest extends RepositoryTestCase {

 	private Git git;

 	@Parameter(0)
 	public boolean useAnnotatedTags;

 	@Parameter(1)
 	public boolean describeUseAllTags;

 	@Parameters(name = "git tag -a {0}?-a: with git describe {1}?--tags:")
 	public static Collection<Boolean[]> getUseAnnotatedTagsValues() {
 		return Arrays.asList(new Boolean[][] { { Boolean.TRUE, Boolean.FALSE },
 				{ Boolean.FALSE, Boolean.FALSE },
 				{ Boolean.TRUE, Boolean.TRUE },
 				{ Boolean.FALSE, Boolean.TRUE } });
 	}

 	@Override
 	public void setUp() throws Exception {
 		super.setUp();
 		git = new Git(db);
 	}

 	@Test(expected = RefNotFoundException.class)
 	public void noTargetSet() throws Exception {
 		git.describe().call();
 	}

 	@Test
 	public void testDescribe() throws Exception {
 		ObjectId c1 = modify("aaa");

 		ObjectId c2 = modify("bbb");
 		tag("alice-t1");

 		ObjectId c3 = modify("ccc");
 		tag("bob-t2");

 		ObjectId c4 = modify("ddd");
 		assertNameStartsWith(c4, "3e563c5");

 		assertNull(describe(c1));
 		assertNull(describe(c1, true, false));
 		assertNull(describe(c1, "a*", "b*", "c*"));
 		assertNull(describe(c2, "bob*"));
 		assertNull(describe(c2, "?ob*"));

 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("alice-t1", describe(c2));
 			assertEquals("alice-t1", describe(c2, "alice*"));
 			assertEquals("alice-t1", describe(c2, "a*", "b*", "c*"));

 			assertEquals("bob-t2", describe(c3));
 			assertEquals("bob-t2-0-g44579eb", describe(c3, true, false));
 			assertEquals("alice-t1-1-g44579eb", describe(c3, "alice*"));
 			assertEquals("alice-t1-1-g44579eb", describe(c3, "a??c?-t*"));
 			assertEquals("bob-t2", describe(c3, "bob*"));
 			assertEquals("bob-t2", describe(c3, "?ob*"));
 			assertEquals("bob-t2", describe(c3, "a*", "b*", "c*"));

 			// the value verified with git-describe(1)
 			assertEquals("bob-t2-1-g3e563c5", describe(c4));
 			assertEquals("bob-t2-1-g3e563c5", describe(c4, true, false));
 			assertEquals("alice-t1-2-g3e563c5", describe(c4, "alice*"));
 			assertEquals("bob-t2-1-g3e563c5", describe(c4, "bob*"));
 			assertEquals("bob-t2-1-g3e563c5", describe(c4, "a*", "b*", "c*"));
 		} else {
 			assertEquals(null, describe(c2));
 			assertEquals(null, describe(c3));
 			assertEquals(null, describe(c4));

 			assertEquals("3747db3", describe(c2, false, true));
 			assertEquals("44579eb", describe(c3, false, true));
 			assertEquals("3e563c5", describe(c4, false, true));
 		}

 		// test default target
 		if (useAnnotatedTags) {
 			assertEquals("bob-t2-1-g3e563c5", git.describe().call());
 			assertEquals("bob-t2-1-g3e563c5",
 					git.describe().setTags(false).call());
 			assertEquals("bob-t2-1-g3e563c5",
 					git.describe().setTags(true).call());
 		} else {
 			assertEquals(null, git.describe().call());
 			assertEquals(null, git.describe().setTags(false).call());
 			assertEquals("bob-t2-1-g3e563c5",
 					git.describe().setTags(true).call());
 		}
 	}

 	@Test
 	public void testDescribeMultiMatch() throws Exception {
 		ObjectId c1 = modify("aaa");
 		tag("v1.0.0");
 		tick();
 		tag("v1.0.1");
 		tick();
 		tag("v1.1.0");
 		tick();
 		tag("v1.1.1");
 		ObjectId c2 = modify("bbb");

 		if (!useAnnotatedTags && !describeUseAllTags) {
 			assertEquals(null, describe(c1));
 			assertEquals(null, describe(c2));

 			assertEquals("fd70040", describe(c1, false, true));
 			assertEquals("b89dead", describe(c2, false, true));

 			return;
 		}

 		// Ensure that if we're interested in any tags, we get the most recent tag
 		// as per Git behaviour since 1.7.1.1
 		if (useAnnotatedTags) {
 			assertEquals("v1.1.1", describe(c1));
 			assertEquals("v1.1.1-1-gb89dead", describe(c2));
 			// Ensure that if we're only interested in one of multiple tags, we get the right match
 			assertEquals("v1.0.1", describe(c1, "v1.0*"));
 			assertEquals("v1.1.1", describe(c1, "v1.1*"));
 			assertEquals("v1.0.1-1-gb89dead", describe(c2, "v1.0*"));
 			assertEquals("v1.1.1-1-gb89dead", describe(c2, "v1.1*"));

 			// Ensure that ordering of match precedence is preserved as per Git behaviour
 			assertEquals("v1.1.1", describe(c1, "v1.0*", "v1.1*"));
 			assertEquals("v1.1.1", describe(c1, "v1.1*", "v1.0*"));
 			assertEquals("v1.1.1-1-gb89dead", describe(c2, "v1.0*", "v1.1*"));
 			assertEquals("v1.1.1-1-gb89dead", describe(c2, "v1.1*", "v1.0*"));
 		} else {
 			// no timestamps so no guarantees on which tag is chosen
 			assertNotNull(describe(c1));
 			assertNotNull(describe(c2));

 			assertNotNull(describe(c1, "v1.0*"));
 			assertNotNull(describe(c1, "v1.1*"));
 			assertNotNull(describe(c2, "v1.0*"));
 			assertNotNull(describe(c2, "v1.1*"));

 			// Ensure that ordering of match precedence is preserved as per Git behaviour
 			assertNotNull(describe(c1, "v1.0*", "v1.1*"));
 			assertNotNull(describe(c1, "v1.1*", "v1.0*"));
 			assertNotNull(describe(c2, "v1.0*", "v1.1*"));
 			assertNotNull(describe(c2, "v1.1*", "v1.0*"));
 		}
 	}

 	/**
 	 * Make sure it finds a tag when not all ancestries include a tag.
 	 *
 	 * <pre>
 	 * c1 -+-&gt; T  -
 	 *     |       |
 	 *     +-&gt; c3 -+-&gt; c4
 	 * </pre>
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void testDescribeBranch() throws Exception {
 		ObjectId c1 = modify("aaa");

 		ObjectId c2 = modify("bbb");
 		tag("t");

 		branch("b", c1);

 		ObjectId c3 = modify("ccc");

 		ObjectId c4 = merge(c2);

 		assertNameStartsWith(c4, "119892b");
 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("2 commits: c4 and c3", "t-2-g119892b", describe(c4));
 		} else {
 			assertEquals(null, describe(c4));

 			assertEquals("119892b", describe(c4, false, true));
 		}
 		assertNull(describe(c3));
 		assertNull(describe(c3, true, false));
 	}

 	private void branch(String name, ObjectId base) throws GitAPIException {
 		git.checkout().setCreateBranch(true).setName(name)
 				.setStartPoint(base.name()).call();
 	}

 	/**
 	 * When t2 dominates t1, it's clearly preferable to describe by using t2.
 	 *
 	 * <pre>
 	 * t1 -+-&gt; t2  -
 	 *     |       |
 	 *     +-&gt; c3 -+-&gt; c4
 	 * </pre>
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void t1DominatesT2() throws Exception {
 		ObjectId c1 = modify("aaa");
 		tag("t1");

 		ObjectId c2 = modify("bbb");
 		tag("t2");

 		branch("b", c1);

 		ObjectId c3 = modify("ccc");
 		assertNameStartsWith(c3, "0244e7f");

 		ObjectId c4 = merge(c2);

 		assertNameStartsWith(c4, "119892b");

 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("t2-2-g119892b", describe(c4)); // 2 commits: c4 and c3
 			assertEquals("t1-1-g0244e7f", describe(c3));
 		} else {
 			assertEquals(null, describe(c4));
 			assertEquals(null, describe(c3));

 			assertEquals("119892b", describe(c4, false, true));
 			assertEquals("0244e7f", describe(c3, false, true));
 		}
 	}

 	/**
 	 * When t1 annotated dominates t2 lightweight tag
 	 *
 	 * <pre>
 	 * t1 -+-> t2  -
 	 *     |       |
 	 *     +-> c3 -+-> c4
 	 * </pre>
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void t1AnnotatedDominatesT2lightweight() throws Exception {
 		ObjectId c1 = modify("aaa");
 		tag("t1", useAnnotatedTags);

 		ObjectId c2 = modify("bbb");
 		tag("t2", false);

 		assertNameStartsWith(c2, "3747db3");
 		if (useAnnotatedTags && !describeUseAllTags) {
 			assertEquals(
 					"only annotated tag t1 expected to be used for describe",
 					"t1-1-g3747db3", describe(c2)); // 1 commits: t2 overridden
 													// by t1
 		} else if (!useAnnotatedTags && !describeUseAllTags) {
 			assertEquals("no commits to describe expected", null, describe(c2));
 		} else {
 			assertEquals("lightweight tag t2 expected in describe", "t2",
 					describe(c2));
 		}

 		branch("b", c1);

 		ObjectId c3 = modify("ccc");

 		assertNameStartsWith(c3, "0244e7f");
 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("t1-1-g0244e7f", describe(c3));
 		}

 		ObjectId c4 = merge(c2);

 		assertNameStartsWith(c4, "119892b");
 		if (describeUseAllTags) {
 			assertEquals(
 					"2 commits for describe commit increment expected since lightweight tag: c4 and c3",
 					"t2-2-g119892b", describe(c4)); // 2 commits: c4 and c3
 		} else if (!useAnnotatedTags && !describeUseAllTags) {
 			assertEquals("no matching commits expected", null, describe(c4));
 		} else {
 			assertEquals(
 					"3 commits for describe commit increment expected since annotated tag: c4 and c3 and c2",
 					"t1-3-g119892b", describe(c4)); //
 		}
 	}

 	/**
 	 * When t1 is nearer than t2, t2 should be found
 	 *
 	 * <pre>
 	 * c1 -+-&gt; c2 -&gt; t1 -+
 	 *     |             |
 	 *     +-&gt; t2 -&gt; c3 -+-&gt; c4
 	 * </pre>
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void t1nearerT2() throws Exception {
 		ObjectId c1 = modify("aaa");
 		modify("bbb");
 		ObjectId t1 = modify("ccc");
 		tag("t1");

 		branch("b", c1);
 		modify("ddd");
 		tag("t2");
 		modify("eee");
 		ObjectId c4 = merge(t1);

 		assertNameStartsWith(c4, "bb389a4");
 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("t1-3-gbb389a4", describe(c4));
 		} else {
 			assertEquals(null, describe(c4));

 			assertEquals("bb389a4", describe(c4, false, true));
 		}
 	}

 	/**
 	 * When t1 and t2 have same depth native git seems to add the depths of both
 	 * paths
 	 *
 	 * <pre>
 	 * c1 -+-&gt; t1 -&gt; c2 -+
 	 *     |             |
 	 *     +-&gt; t2 -&gt; c3 -+-&gt; c4
 	 * </pre>
 	 *
 	 * @throws Exception
 	 */
 	@Test
 	public void t1sameDepthT2() throws Exception {
 		ObjectId c1 = modify("aaa");
 		modify("bbb");
 		tag("t1");
 		ObjectId c2 = modify("ccc");

 		branch("b", c1);
 		modify("ddd");
 		tag("t2");
 		modify("eee");
 		ObjectId c4 = merge(c2);

 		assertNameStartsWith(c4, "bb389a4");
 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("t2-4-gbb389a4", describe(c4));
 		} else {
 			assertEquals(null, describe(c4));

 			assertEquals("bb389a4", describe(c4, false, true));
 		}
 	}

 	@Test
 	public void globMatchWithSlashes() throws Exception {
 		ObjectId c1 = modify("aaa");
 		tag("a/b/version");
 		ObjectId c2 = modify("bbb");
 		tag("a/b/version2");
 		if (useAnnotatedTags || describeUseAllTags) {
 			assertEquals("a/b/version", describe(c1, "*/version*"));
 			assertEquals("a/b/version2", describe(c2, "*/version*"));
 		} else {
 			assertNull(describe(c1));
 			assertNull(describe(c1, "*/version*"));
 			assertNull(describe(c2));
 			assertNull(describe(c2, "*/version*"));
 		}
 	}

 	private ObjectId merge(ObjectId c2) throws GitAPIException {
 		return git.merge().include(c2).call().getNewHead();
 	}

 	private ObjectId modify(String content) throws Exception {
 		File a = new File(db.getWorkTree(), "a.txt");
 		touch(a, content);
 		return git.commit().setAll(true).setMessage(content).call().getId();
 	}

 	private void tag(String tag) throws GitAPIException {
 		tag(tag, this.useAnnotatedTags);
 	}

 	private void tag(String tag, boolean annotatedTag) throws GitAPIException {
 		TagCommand tagCommand = git.tag().setName(tag)
 				.setAnnotated(annotatedTag);
 		if (annotatedTag) {
 			tagCommand.setMessage(tag);
 		}
 		tagCommand.call();
 	}

 	private static void touch(File f, String contents) throws Exception {
 		try (BufferedWriter w = Files.newBufferedWriter(f.toPath(), UTF_8)) {
 			w.write(contents);
 		}
 	}

 	private String describe(ObjectId c1, boolean longDesc, boolean always)
 			throws GitAPIException, IOException {
 		return git.describe().setTarget(c1).setTags(describeUseAllTags)
 				.setLong(longDesc).setAlways(always).call();
 	}

 	private String describe(ObjectId c1) throws GitAPIException, IOException {
 		return describe(c1, false, false);
 	}

 	private String describe(ObjectId c1, String... patterns) throws Exception {
 		return git.describe().setTarget(c1).setTags(describeUseAllTags)
 				.setMatch(patterns).call();
 	}

 	private static void assertNameStartsWith(ObjectId c4, String prefix) {
 		assertTrue(c4.name(), c4.name().startsWith(prefix));
 	}
 }
	/*
	* Copyright (C) 2013, CloudBees, Inc.
	* 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.api;

	import static java.nio.charset.StandardCharsets.UTF_8;
	import static org.junit.Assert.assertEquals;
	import static org.junit.Assert.assertNull;
	import static org.junit.Assert.assertNotNull;
	import static org.junit.Assert.assertTrue;

	import java.io.BufferedWriter;
	import java.io.File;
	import java.io.IOException;
	import java.nio.file.Files;
	import java.util.Arrays;
	import java.util.Collection;

	import org.eclipse.jgit.api.errors.GitAPIException;
	import org.eclipse.jgit.api.errors.RefNotFoundException;
	import org.eclipse.jgit.junit.RepositoryTestCase;
	import org.eclipse.jgit.lib.ObjectId;
	import org.junit.Test;
	import org.junit.runner.RunWith;
	import org.junit.runners.Parameterized;
	import org.junit.runners.Parameterized.Parameter;
	import org.junit.runners.Parameterized.Parameters;

	@RunWith(Parameterized.class)
	public class DescribeCommandTest extends RepositoryTestCase {

	private Git git;

	@Parameter(0)
	public boolean useAnnotatedTags;

	@Parameter(1)
	public boolean describeUseAllTags;

	@Parameters(name = "git tag -a {0}?-a: with git describe {1}?--tags:")
	public static Collection<Boolean[]> getUseAnnotatedTagsValues() {
	return Arrays.asList(new Boolean[][] { { Boolean.TRUE, Boolean.FALSE },
	{ Boolean.FALSE, Boolean.FALSE },
	{ Boolean.TRUE, Boolean.TRUE },
	{ Boolean.FALSE, Boolean.TRUE } });
	}

	@Override
	public void setUp() throws Exception {
	super.setUp();
	git = new Git(db);
	}

	@Test(expected = RefNotFoundException.class)
	public void noTargetSet() throws Exception {
	git.describe().call();
	}

	@Test
	public void testDescribe() throws Exception {
	ObjectId c1 = modify("aaa");

	ObjectId c2 = modify("bbb");
	tag("alice-t1");

	ObjectId c3 = modify("ccc");
	tag("bob-t2");

	ObjectId c4 = modify("ddd");
	assertNameStartsWith(c4, "3e563c5");

	assertNull(describe(c1));
	assertNull(describe(c1, true, false));
	assertNull(describe(c1, "a", "b", "c*"));
	assertNull(describe(c2, "bob*"));
	assertNull(describe(c2, "?ob*"));

	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("alice-t1", describe(c2));
	assertEquals("alice-t1", describe(c2, "alice*"));
	assertEquals("alice-t1", describe(c2, "a", "b", "c*"));

	assertEquals("bob-t2", describe(c3));
	assertEquals("bob-t2-0-g44579eb", describe(c3, true, false));
	assertEquals("alice-t1-1-g44579eb", describe(c3, "alice*"));
	assertEquals("alice-t1-1-g44579eb", describe(c3, "a??c?-t*"));
	assertEquals("bob-t2", describe(c3, "bob*"));
	assertEquals("bob-t2", describe(c3, "?ob*"));
	assertEquals("bob-t2", describe(c3, "a", "b", "c*"));

	// the value verified with git-describe(1)
	assertEquals("bob-t2-1-g3e563c5", describe(c4));
	assertEquals("bob-t2-1-g3e563c5", describe(c4, true, false));
	assertEquals("alice-t1-2-g3e563c5", describe(c4, "alice*"));
	assertEquals("bob-t2-1-g3e563c5", describe(c4, "bob*"));
	assertEquals("bob-t2-1-g3e563c5", describe(c4, "a", "b", "c*"));
	} else {
	assertEquals(null, describe(c2));
	assertEquals(null, describe(c3));
	assertEquals(null, describe(c4));

	assertEquals("3747db3", describe(c2, false, true));
	assertEquals("44579eb", describe(c3, false, true));
	assertEquals("3e563c5", describe(c4, false, true));
	}

	// test default target
	if (useAnnotatedTags) {
	assertEquals("bob-t2-1-g3e563c5", git.describe().call());
	assertEquals("bob-t2-1-g3e563c5",
	git.describe().setTags(false).call());
	assertEquals("bob-t2-1-g3e563c5",
	git.describe().setTags(true).call());
	} else {
	assertEquals(null, git.describe().call());
	assertEquals(null, git.describe().setTags(false).call());
	assertEquals("bob-t2-1-g3e563c5",
	git.describe().setTags(true).call());
	}
	}

	@Test
	public void testDescribeMultiMatch() throws Exception {
	ObjectId c1 = modify("aaa");
	tag("v1.0.0");
	tick();
	tag("v1.0.1");
	tick();
	tag("v1.1.0");
	tick();
	tag("v1.1.1");
	ObjectId c2 = modify("bbb");

	if (!useAnnotatedTags && !describeUseAllTags) {
	assertEquals(null, describe(c1));
	assertEquals(null, describe(c2));

	assertEquals("fd70040", describe(c1, false, true));
	assertEquals("b89dead", describe(c2, false, true));

	return;
	}

	// Ensure that if we're interested in any tags, we get the most recent tag
	// as per Git behaviour since 1.7.1.1
	if (useAnnotatedTags) {
	assertEquals("v1.1.1", describe(c1));
	assertEquals("v1.1.1-1-gb89dead", describe(c2));
	// Ensure that if we're only interested in one of multiple tags, we get the right match
	assertEquals("v1.0.1", describe(c1, "v1.0*"));
	assertEquals("v1.1.1", describe(c1, "v1.1*"));
	assertEquals("v1.0.1-1-gb89dead", describe(c2, "v1.0*"));
	assertEquals("v1.1.1-1-gb89dead", describe(c2, "v1.1*"));

	// Ensure that ordering of match precedence is preserved as per Git behaviour
	assertEquals("v1.1.1", describe(c1, "v1.0", "v1.1"));
	assertEquals("v1.1.1", describe(c1, "v1.1", "v1.0"));
	assertEquals("v1.1.1-1-gb89dead", describe(c2, "v1.0", "v1.1"));
	assertEquals("v1.1.1-1-gb89dead", describe(c2, "v1.1", "v1.0"));
	} else {
	// no timestamps so no guarantees on which tag is chosen
	assertNotNull(describe(c1));
	assertNotNull(describe(c2));

	assertNotNull(describe(c1, "v1.0*"));
	assertNotNull(describe(c1, "v1.1*"));
	assertNotNull(describe(c2, "v1.0*"));
	assertNotNull(describe(c2, "v1.1*"));

	// Ensure that ordering of match precedence is preserved as per Git behaviour
	assertNotNull(describe(c1, "v1.0", "v1.1"));
	assertNotNull(describe(c1, "v1.1", "v1.0"));
	assertNotNull(describe(c2, "v1.0", "v1.1"));
	assertNotNull(describe(c2, "v1.1", "v1.0"));
	}
	}

	/**
	* Make sure it finds a tag when not all ancestries include a tag.
	*
	* <pre>
	* c1 -+-> T -
	* \| \|
	* +-> c3 -+-> c4
	* </pre>
	*
	* @throws Exception
	*/
	@Test
	public void testDescribeBranch() throws Exception {
	ObjectId c1 = modify("aaa");

	ObjectId c2 = modify("bbb");
	tag("t");

	branch("b", c1);

	ObjectId c3 = modify("ccc");

	ObjectId c4 = merge(c2);

	assertNameStartsWith(c4, "119892b");
	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("2 commits: c4 and c3", "t-2-g119892b", describe(c4));
	} else {
	assertEquals(null, describe(c4));

	assertEquals("119892b", describe(c4, false, true));
	}
	assertNull(describe(c3));
	assertNull(describe(c3, true, false));
	}

	private void branch(String name, ObjectId base) throws GitAPIException {
	git.checkout().setCreateBranch(true).setName(name)
	.setStartPoint(base.name()).call();
	}

	/**
	* When t2 dominates t1, it's clearly preferable to describe by using t2.
	*
	* <pre>
	* t1 -+-> t2 -
	* \| \|
	* +-> c3 -+-> c4
	* </pre>
	*
	* @throws Exception
	*/
	@Test
	public void t1DominatesT2() throws Exception {
	ObjectId c1 = modify("aaa");
	tag("t1");

	ObjectId c2 = modify("bbb");
	tag("t2");

	branch("b", c1);

	ObjectId c3 = modify("ccc");
	assertNameStartsWith(c3, "0244e7f");

	ObjectId c4 = merge(c2);

	assertNameStartsWith(c4, "119892b");

	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("t2-2-g119892b", describe(c4)); // 2 commits: c4 and c3
	assertEquals("t1-1-g0244e7f", describe(c3));
	} else {
	assertEquals(null, describe(c4));
	assertEquals(null, describe(c3));

	assertEquals("119892b", describe(c4, false, true));
	assertEquals("0244e7f", describe(c3, false, true));
	}
	}

	/**
	* When t1 annotated dominates t2 lightweight tag
	*
	* <pre>
	* t1 -+-> t2 -
	* \| \|
	* +-> c3 -+-> c4
	* </pre>
	*
	* @throws Exception
	*/
	@Test
	public void t1AnnotatedDominatesT2lightweight() throws Exception {
	ObjectId c1 = modify("aaa");
	tag("t1", useAnnotatedTags);

	ObjectId c2 = modify("bbb");
	tag("t2", false);

	assertNameStartsWith(c2, "3747db3");
	if (useAnnotatedTags && !describeUseAllTags) {
	assertEquals(
	"only annotated tag t1 expected to be used for describe",
	"t1-1-g3747db3", describe(c2)); // 1 commits: t2 overridden
	// by t1
	} else if (!useAnnotatedTags && !describeUseAllTags) {
	assertEquals("no commits to describe expected", null, describe(c2));
	} else {
	assertEquals("lightweight tag t2 expected in describe", "t2",
	describe(c2));
	}

	branch("b", c1);

	ObjectId c3 = modify("ccc");

	assertNameStartsWith(c3, "0244e7f");
	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("t1-1-g0244e7f", describe(c3));
	}

	ObjectId c4 = merge(c2);

	assertNameStartsWith(c4, "119892b");
	if (describeUseAllTags) {
	assertEquals(
	"2 commits for describe commit increment expected since lightweight tag: c4 and c3",
	"t2-2-g119892b", describe(c4)); // 2 commits: c4 and c3
	} else if (!useAnnotatedTags && !describeUseAllTags) {
	assertEquals("no matching commits expected", null, describe(c4));
	} else {
	assertEquals(
	"3 commits for describe commit increment expected since annotated tag: c4 and c3 and c2",
	"t1-3-g119892b", describe(c4)); //
	}
	}

	/**
	* When t1 is nearer than t2, t2 should be found
	*
	* <pre>
	* c1 -+-> c2 -> t1 -+
	* \| \|
	* +-> t2 -> c3 -+-> c4
	* </pre>
	*
	* @throws Exception
	*/
	@Test
	public void t1nearerT2() throws Exception {
	ObjectId c1 = modify("aaa");
	modify("bbb");
	ObjectId t1 = modify("ccc");
	tag("t1");

	branch("b", c1);
	modify("ddd");
	tag("t2");
	modify("eee");
	ObjectId c4 = merge(t1);

	assertNameStartsWith(c4, "bb389a4");
	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("t1-3-gbb389a4", describe(c4));
	} else {
	assertEquals(null, describe(c4));

	assertEquals("bb389a4", describe(c4, false, true));
	}
	}

	/**
	* When t1 and t2 have same depth native git seems to add the depths of both
	* paths
	*
	* <pre>
	* c1 -+-> t1 -> c2 -+
	* \| \|
	* +-> t2 -> c3 -+-> c4
	* </pre>
	*
	* @throws Exception
	*/
	@Test
	public void t1sameDepthT2() throws Exception {
	ObjectId c1 = modify("aaa");
	modify("bbb");
	tag("t1");
	ObjectId c2 = modify("ccc");

	branch("b", c1);
	modify("ddd");
	tag("t2");
	modify("eee");
	ObjectId c4 = merge(c2);

	assertNameStartsWith(c4, "bb389a4");
	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("t2-4-gbb389a4", describe(c4));
	} else {
	assertEquals(null, describe(c4));

	assertEquals("bb389a4", describe(c4, false, true));
	}
	}

	@Test
	public void globMatchWithSlashes() throws Exception {
	ObjectId c1 = modify("aaa");
	tag("a/b/version");
	ObjectId c2 = modify("bbb");
	tag("a/b/version2");
	if (useAnnotatedTags \|\| describeUseAllTags) {
	assertEquals("a/b/version", describe(c1, "/version"));
	assertEquals("a/b/version2", describe(c2, "/version"));
	} else {
	assertNull(describe(c1));
	assertNull(describe(c1, "/version"));
	assertNull(describe(c2));
	assertNull(describe(c2, "/version"));
	}
	}

	private ObjectId merge(ObjectId c2) throws GitAPIException {
	return git.merge().include(c2).call().getNewHead();
	}

	private ObjectId modify(String content) throws Exception {
	File a = new File(db.getWorkTree(), "a.txt");
	touch(a, content);
	return git.commit().setAll(true).setMessage(content).call().getId();
	}

	private void tag(String tag) throws GitAPIException {
	tag(tag, this.useAnnotatedTags);
	}

	private void tag(String tag, boolean annotatedTag) throws GitAPIException {
	TagCommand tagCommand = git.tag().setName(tag)
	.setAnnotated(annotatedTag);
	if (annotatedTag) {
	tagCommand.setMessage(tag);
	}
	tagCommand.call();
	}

	private static void touch(File f, String contents) throws Exception {
	try (BufferedWriter w = Files.newBufferedWriter(f.toPath(), UTF_8)) {
	w.write(contents);
	}
	}

	private String describe(ObjectId c1, boolean longDesc, boolean always)
	throws GitAPIException, IOException {
	return git.describe().setTarget(c1).setTags(describeUseAllTags)
	.setLong(longDesc).setAlways(always).call();
	}

	private String describe(ObjectId c1) throws GitAPIException, IOException {
	return describe(c1, false, false);
	}

	private String describe(ObjectId c1, String... patterns) throws Exception {
	return git.describe().setTarget(c1).setTags(describeUseAllTags)
	.setMatch(patterns).call();
	}

	private static void assertNameStartsWith(ObjectId c4, String prefix) {
	assertTrue(c4.name(), c4.name().startsWith(prefix));
	}
	}