Add support for creating a stashed commit

Adds a new command to stash the index and working directory
changes in a commit stored in refs/stash

Bug: 309355
Change-Id: I2ce85b1601b74b07e286a3f99feb358dfbdfe29c
Signed-off-by: Chris Aniszczyk <zx@twitter.com>

1 files changed, 397 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
new file mode 100644
index 0000000000..b91a50a945
--- /dev/null
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
@@ -0,0 +1,397 @@
+/*
+ * Copyright (C) 2012, GitHub 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 org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.List;
+
+import org.eclipse.jgit.diff.DiffEntry;
+import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.RepositoryTestCase;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevWalk;
+import org.eclipse.jgit.treewalk.TreeWalk;
+import org.eclipse.jgit.treewalk.filter.TreeFilter;
+import org.eclipse.jgit.util.FileUtils;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Unit tests of {@link StashCreateCommand}
+ */
+public class StashCreateCommandTest extends RepositoryTestCase {
+
+	private RevCommit head;
+
+	private Git git;
+
+	private File committedFile;
+
+	@Before
+	public void setUp() throws Exception {
+		super.setUp();
+		git = Git.wrap(db);
+		committedFile = writeTrashFile("file.txt", "content");
+		git.add().addFilepattern("file.txt").call();
+		head = git.commit().setMessage("add file").call();
+		assertNotNull(head);
+	}
+
+	/**
+	 * Core validation to be performed on all stashed commits
+	 *
+	 * @param commit
+	 * @throws IOException
+	 */
+	private void validateStashedCommit(final RevCommit commit)
+			throws IOException {
+		assertNotNull(commit);
+		Ref stashRef = db.getRef(Constants.R_STASH);
+		assertNotNull(stashRef);
+		assertEquals(commit, stashRef.getObjectId());
+		assertNotNull(commit.getAuthorIdent());
+		assertEquals(commit.getAuthorIdent(), commit.getCommitterIdent());
+		assertEquals(2, commit.getParentCount());
+
+		// Load parents
+		RevWalk walk = new RevWalk(db);
+		try {
+			for (RevCommit parent : commit.getParents())
+				walk.parseBody(parent);
+		} finally {
+			walk.release();
+		}
+
+		assertEquals(1, commit.getParent(1).getParentCount());
+		assertEquals(head, commit.getParent(1).getParent(0));
+		assertFalse("Head tree matches stashed commit tree", commit.getTree()
+				.equals(head.getTree()));
+		assertEquals(head, commit.getParent(0));
+		assertFalse(commit.getFullMessage().equals(
+				commit.getParent(1).getFullMessage()));
+	}
+
+	private TreeWalk createTreeWalk() {
+		TreeWalk walk = new TreeWalk(db);
+		walk.setRecursive(true);
+		walk.setFilter(TreeFilter.ANY_DIFF);
+		return walk;
+	}
+
+	private List<DiffEntry> diffWorkingAgainstHead(final RevCommit commit)
+			throws IOException {
+		TreeWalk walk = createTreeWalk();
+		try {
+			walk.addTree(commit.getParent(0).getTree());
+			walk.addTree(commit.getTree());
+			return DiffEntry.scan(walk);
+		} finally {
+			walk.release();
+		}
+	}
+
+	private List<DiffEntry> diffIndexAgainstHead(final RevCommit commit)
+			throws IOException {
+		TreeWalk walk = createTreeWalk();
+		try {
+			walk.addTree(commit.getParent(0).getTree());
+			walk.addTree(commit.getParent(1).getTree());
+			return DiffEntry.scan(walk);
+		} finally {
+			walk.release();
+		}
+	}
+
+	@Test
+	public void noLocalChanges() throws Exception {
+		assertNull(git.stashCreate().call());
+	}
+
+	@Test
+	public void workingDirectoryDelete() throws Exception {
+		deleteTrashFile("file.txt");
+		RevCommit stashed = git.stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(committedFile));
+		validateStashedCommit(stashed);
+
+		assertEquals(head.getTree(), stashed.getParent(1).getTree());
+
+		List<DiffEntry> diffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, diffs.size());
+		assertEquals(DiffEntry.ChangeType.DELETE, diffs.get(0).getChangeType());
+		assertEquals("file.txt", diffs.get(0).getOldPath());
+	}
+
+	@Test
+	public void indexAdd() throws Exception {
+		File addedFile = writeTrashFile("file2.txt", "content2");
+		git.add().addFilepattern("file2.txt").call();
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertFalse(addedFile.exists());
+		validateStashedCommit(stashed);
+
+		assertEquals(stashed.getTree(), stashed.getParent(1).getTree());
+
+		List<DiffEntry> diffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, diffs.size());
+		assertEquals(DiffEntry.ChangeType.ADD, diffs.get(0).getChangeType());
+		assertEquals("file2.txt", diffs.get(0).getNewPath());
+	}
+
+	@Test
+	public void indexDelete() throws Exception {
+		git.rm().addFilepattern("file.txt").call();
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(committedFile));
+		validateStashedCommit(stashed);
+
+		assertEquals(stashed.getTree(), stashed.getParent(1).getTree());
+
+		List<DiffEntry> diffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, diffs.size());
+		assertEquals(DiffEntry.ChangeType.DELETE, diffs.get(0).getChangeType());
+		assertEquals("file.txt", diffs.get(0).getOldPath());
+	}
+
+	@Test
+	public void workingDirectoryModify() throws Exception {
+		writeTrashFile("file.txt", "content2");
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(committedFile));
+		validateStashedCommit(stashed);
+
+		assertEquals(head.getTree(), stashed.getParent(1).getTree());
+
+		List<DiffEntry> diffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, diffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, diffs.get(0).getChangeType());
+		assertEquals("file.txt", diffs.get(0).getNewPath());
+	}
+
+	@Test
+	public void workingDirectoryModifyInSubfolder() throws Exception {
+		String path = "d1/d2/f.txt";
+		File subfolderFile = writeTrashFile(path, "content");
+		git.add().addFilepattern(path).call();
+		head = git.commit().setMessage("add file").call();
+
+		writeTrashFile(path, "content2");
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(subfolderFile));
+		validateStashedCommit(stashed);
+
+		assertEquals(head.getTree(), stashed.getParent(1).getTree());
+
+		List<DiffEntry> diffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, diffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, diffs.get(0).getChangeType());
+		assertEquals(path, diffs.get(0).getNewPath());
+	}
+
+	@Test
+	public void workingDirectoryModifyIndexChanged() throws Exception {
+		writeTrashFile("file.txt", "content2");
+		git.add().addFilepattern("file.txt").call();
+		writeTrashFile("file.txt", "content3");
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(committedFile));
+		validateStashedCommit(stashed);
+
+		assertFalse(stashed.getTree().equals(stashed.getParent(1).getTree()));
+
+		List<DiffEntry> workingDiffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, workingDiffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, workingDiffs.get(0)
+				.getChangeType());
+		assertEquals("file.txt", workingDiffs.get(0).getNewPath());
+
+		List<DiffEntry> indexDiffs = diffIndexAgainstHead(stashed);
+		assertEquals(1, indexDiffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, indexDiffs.get(0)
+				.getChangeType());
+		assertEquals("file.txt", indexDiffs.get(0).getNewPath());
+
+		assertEquals(workingDiffs.get(0).getOldId(), indexDiffs.get(0)
+				.getOldId());
+		assertFalse(workingDiffs.get(0).getNewId()
+				.equals(indexDiffs.get(0).getNewId()));
+	}
+
+	@Test
+	public void workingDirectoryCleanIndexModify() throws Exception {
+		writeTrashFile("file.txt", "content2");
+		git.add().addFilepattern("file.txt").call();
+		writeTrashFile("file.txt", "content");
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(committedFile));
+		validateStashedCommit(stashed);
+
+		assertTrue(stashed.getTree().equals(stashed.getParent(1).getTree()));
+
+		List<DiffEntry> workingDiffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, workingDiffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, workingDiffs.get(0)
+				.getChangeType());
+		assertEquals("file.txt", workingDiffs.get(0).getNewPath());
+
+		List<DiffEntry> indexDiffs = diffIndexAgainstHead(stashed);
+		assertEquals(1, indexDiffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, indexDiffs.get(0)
+				.getChangeType());
+		assertEquals("file.txt", indexDiffs.get(0).getNewPath());
+
+		assertEquals(workingDiffs.get(0).getOldId(), indexDiffs.get(0)
+				.getOldId());
+		assertTrue(workingDiffs.get(0).getNewId()
+				.equals(indexDiffs.get(0).getNewId()));
+	}
+
+	@Test
+	public void workingDirectoryDeleteIndexAdd() throws Exception {
+		String path = "file2.txt";
+		File added = writeTrashFile(path, "content2");
+		assertTrue(added.exists());
+		git.add().addFilepattern(path).call();
+		FileUtils.delete(added);
+		assertFalse(added.exists());
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertFalse(added.exists());
+
+		validateStashedCommit(stashed);
+
+		assertTrue(stashed.getTree().equals(stashed.getParent(1).getTree()));
+
+		List<DiffEntry> workingDiffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, workingDiffs.size());
+		assertEquals(DiffEntry.ChangeType.ADD, workingDiffs.get(0)
+				.getChangeType());
+		assertEquals(path, workingDiffs.get(0).getNewPath());
+
+		List<DiffEntry> indexDiffs = diffIndexAgainstHead(stashed);
+		assertEquals(1, indexDiffs.size());
+		assertEquals(DiffEntry.ChangeType.ADD, indexDiffs.get(0)
+				.getChangeType());
+		assertEquals(path, indexDiffs.get(0).getNewPath());
+
+		assertEquals(workingDiffs.get(0).getOldId(), indexDiffs.get(0)
+				.getOldId());
+		assertTrue(workingDiffs.get(0).getNewId()
+				.equals(indexDiffs.get(0).getNewId()));
+	}
+
+	@Test
+	public void workingDirectoryDeleteIndexEdit() throws Exception {
+		File edited = writeTrashFile("file.txt", "content2");
+		git.add().addFilepattern("file.txt").call();
+		FileUtils.delete(edited);
+		assertFalse(edited.exists());
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertEquals("content", read(committedFile));
+		validateStashedCommit(stashed);
+
+		assertFalse(stashed.getTree().equals(stashed.getParent(1).getTree()));
+
+		List<DiffEntry> workingDiffs = diffWorkingAgainstHead(stashed);
+		assertEquals(1, workingDiffs.size());
+		assertEquals(DiffEntry.ChangeType.DELETE, workingDiffs.get(0)
+				.getChangeType());
+		assertEquals("file.txt", workingDiffs.get(0).getOldPath());
+
+		List<DiffEntry> indexDiffs = diffIndexAgainstHead(stashed);
+		assertEquals(1, indexDiffs.size());
+		assertEquals(DiffEntry.ChangeType.MODIFY, indexDiffs.get(0)
+				.getChangeType());
+		assertEquals("file.txt", indexDiffs.get(0).getNewPath());
+
+		assertEquals(workingDiffs.get(0).getOldId(), indexDiffs.get(0)
+				.getOldId());
+		assertFalse(workingDiffs.get(0).getNewId()
+				.equals(indexDiffs.get(0).getNewId()));
+	}
+
+	@Test
+	public void multipleEdits() throws Exception {
+		git.rm().addFilepattern("file.txt").call();
+		File addedFile = writeTrashFile("file2.txt", "content2");
+		git.add().addFilepattern("file2.txt").call();
+
+		RevCommit stashed = Git.wrap(db).stashCreate().call();
+		assertNotNull(stashed);
+		assertFalse(addedFile.exists());
+		validateStashedCommit(stashed);
+
+		assertEquals(stashed.getTree(), stashed.getParent(1).getTree());
+
+		List<DiffEntry> diffs = diffWorkingAgainstHead(stashed);
+		assertEquals(2, diffs.size());
+		assertEquals(DiffEntry.ChangeType.DELETE, diffs.get(0).getChangeType());
+		assertEquals("file.txt", diffs.get(0).getOldPath());
+		assertEquals(DiffEntry.ChangeType.ADD, diffs.get(1).getChangeType());
+		assertEquals("file2.txt", diffs.get(1).getNewPath());
+	}
+}