TestRepository: Optionally insert Change-Id in commit message

Copied the implementation from CommitCommand.

Change-Id: Iade0e2d70bde70cfa830fe23bcc41959b011a14a

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java

@@ -96,6 +96,7 @@
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.treewalk.TreeWalk;
 import org.eclipse.jgit.treewalk.filter.PathFilterGroup;
+import org.eclipse.jgit.util.ChangeIdUtil;
 import org.eclipse.jgit.util.FileUtils;
 import org.eclipse.jgit.util.io.SafeBufferedOutputStream;
 
@@ -749,6 +750,8 @@ public class CommitBuilder {
 		private PersonIdent author;
 		private PersonIdent committer;
 
+		private boolean insertChangeId;
+
 		CommitBuilder() {
 			branch = null;
 		}
@@ -856,6 +859,11 @@ public CommitBuilder committer(PersonIdent c) {
 			return this;
 		}
 
+		public CommitBuilder insertChangeId() {
+			insertChangeId = true;
+			return this;
+		}
+
 		public RevCommit create() throws Exception {
 			if (self == null) {
 				TestRepository.this.tick(tick);
@@ -869,7 +877,6 @@ public RevCommit create() throws Exception {
 					c.setAuthor(author);
 				if (committer != null)
 					c.setCommitter(committer);
-				c.setMessage(message);
 
 				ObjectId commitId;
 				try (ObjectInserter ins = inserter) {
@@ -877,6 +884,9 @@ public RevCommit create() throws Exception {
 						c.setTreeId(topLevelTree);
 					else
 						c.setTreeId(tree.writeTree(ins));
+					if (insertChangeId)
+						insertChangeId(c);
+					c.setMessage(message);
 					commitId = ins.insert(c);
 					ins.flush();
 				}
@@ -888,6 +898,20 @@ public RevCommit create() throws Exception {
 			return self;
 		}
 
+		private void insertChangeId(org.eclipse.jgit.lib.CommitBuilder c)
+				throws IOException {
+			ObjectId firstParentId = null;
+			if (!parents.isEmpty())
+				firstParentId = parents.get(0);
+			ObjectId changeId = ChangeIdUtil.computeChangeId(c.getTreeId(),
+					firstParentId, c.getAuthor(), c.getCommitter(), message);
+			message = ChangeIdUtil.insertId(message, changeId);
+			if (changeId != null)
+				message = message.replaceAll("\nChange-Id: I" //$NON-NLS-1$
+						+ ObjectId.zeroId().getName() + "\n", "\nChange-Id: I" //$NON-NLS-1$ //$NON-NLS-2$
+						+ changeId.getName() + "\n"); //$NON-NLS-1$
+		}
+
 		public CommitBuilder child() throws Exception {
 			return new CommitBuilder(this);
 		}

org.eclipse.jgit.test/tst/org/eclipse/jgit/junit/TestRepositoryTest.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2015, Google 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.junit;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.util.regex.Pattern;
+
+import org.eclipse.jgit.internal.storage.dfs.DfsRepositoryDescription;
+import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevWalk;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class TestRepositoryTest {
+	private TestRepository<InMemoryRepository> tr;
+	private RevWalk rw;
+
+	@Before
+	public void setUp() throws Exception {
+		tr = new TestRepository<>(new InMemoryRepository(
+				new DfsRepositoryDescription("test")));
+		rw = tr.getRevWalk();
+	}
+
+	@After
+	public void tearDown() {
+		rw.close();
+		tr.getRepository().close();
+	}
+
+	@Test
+	public void insertChangeId() throws Exception {
+		RevCommit c1 = tr.commit().message("message").insertChangeId().create();
+		rw.parseBody(c1);
+		assertTrue(Pattern.matches(
+				"^message\n\nChange-Id: I[0-9a-f]{40}\n$", c1.getFullMessage()));
+
+		RevCommit c2 = tr.commit().message("").insertChangeId().create();
+		rw.parseBody(c2);
+		assertEquals("\n\nChange-Id: I0000000000000000000000000000000000000000\n",
+				c2.getFullMessage());
+	}
+}