Allow to include untracked files in stash operations.

Unstashed changes are saved in a commit which is added as an additional
parent to the stash commit.
This behaviour is fully compatible with C Git stashing of untracked
files.

Bug: 434411
Change-Id: I2af784deb0c2320bb57bc4fd472a8daad8674e7d
Signed-off-by: Andreas Hermann <a.v.hermann@gmail.com>

2 files changed, 133 insertions, 4 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashApplyCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashApplyCommandTest.java
index 2834100389..95b14192c9 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashApplyCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashApplyCommandTest.java
@@ -608,7 +608,8 @@ public class StashApplyCommandTest extends RepositoryTestCase {
 			fail("Exception not thrown");
 		} catch (JGitInternalException e) {
 			assertEquals(MessageFormat.format(
-					JGitText.get().stashCommitMissingTwoParents, head.name()),
+					JGitText.get().stashCommitIncorrectNumberOfParents,
+					head.name(), 0),
 					e.getMessage());
 		}
 	}
@@ -648,4 +649,91 @@ public class StashApplyCommandTest extends RepositoryTestCase {
 
 		assertFalse(file.exists());
 	}
+
+	@Test
+	public void untrackedFileNotIncluded() throws Exception {
+		String untrackedPath = "untracked.txt";
+		File untrackedFile = writeTrashFile(untrackedPath, "content");
+		// at least one modification needed
+		writeTrashFile(PATH, "content2");
+		git.add().addFilepattern(PATH).call();
+		git.stashCreate().call();
+		assertTrue(untrackedFile.exists());
+
+		git.stashApply().setStashRef("stash@{0}").call();
+		assertTrue(untrackedFile.exists());
+
+		Status status = git.status().call();
+		assertEquals(1, status.getUntracked().size());
+		assertTrue(status.getUntracked().contains(untrackedPath));
+		assertEquals(1, status.getChanged().size());
+		assertTrue(status.getChanged().contains(PATH));
+		assertTrue(status.getAdded().isEmpty());
+		assertTrue(status.getConflicting().isEmpty());
+		assertTrue(status.getMissing().isEmpty());
+		assertTrue(status.getRemoved().isEmpty());
+		assertTrue(status.getModified().isEmpty());
+	}
+
+	@Test
+	public void untrackedFileIncluded() throws Exception {
+		String path = "a/b/untracked.txt";
+		File untrackedFile = writeTrashFile(path, "content");
+		RevCommit stashedCommit = git.stashCreate().setIncludeUntracked(true)
+				.call();
+		assertNotNull(stashedCommit);
+		assertFalse(untrackedFile.exists());
+		deleteTrashFile("a/b"); // checkout should create parent dirs
+
+		git.stashApply().setStashRef("stash@{0}").call();
+		assertTrue(untrackedFile.exists());
+		assertEquals("content", read(path));
+
+		Status status = git.status().call();
+		assertEquals(1, status.getUntracked().size());
+		assertTrue(status.getAdded().isEmpty());
+		assertTrue(status.getChanged().isEmpty());
+		assertTrue(status.getConflicting().isEmpty());
+		assertTrue(status.getMissing().isEmpty());
+		assertTrue(status.getRemoved().isEmpty());
+		assertTrue(status.getModified().isEmpty());
+		assertTrue(status.getUntracked().contains(path));
+	}
+
+	@Test
+	public void untrackedFileConflictsWithCommit() throws Exception {
+		String path = "untracked.txt";
+		writeTrashFile(path, "untracked");
+		git.stashCreate().setIncludeUntracked(true).call();
+
+		writeTrashFile(path, "committed");
+		head = git.commit().setMessage("add file").call();
+		git.add().addFilepattern(path).call();
+		git.commit().setMessage("conflicting commit").call();
+
+		try {
+			git.stashApply().setStashRef("stash@{0}").call();
+			fail("StashApplyFailureException should be thrown.");
+		} catch (StashApplyFailureException e) {
+			assertEquals(e.getMessage(), JGitText.get().stashApplyConflict);
+		}
+		assertEquals("committed", read(path));
+	}
+
+	@Test
+	public void untrackedFileConflictsWithWorkingDirectory()
+			throws Exception {
+		String path = "untracked.txt";
+		writeTrashFile(path, "untracked");
+		git.stashCreate().setIncludeUntracked(true).call();
+
+		writeTrashFile(path, "working-directory");
+		try {
+			git.stashApply().setStashRef("stash@{0}").call();
+			fail("StashApplyFailureException should be thrown.");
+		} catch (StashApplyFailureException e) {
+			assertEquals(e.getMessage(), JGitText.get().stashApplyConflict);
+		}
+		assertEquals("working-directory", read(path));
+	}
 }
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
index 030dc9f4a1..387120342f 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
@@ -80,6 +80,8 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 
 	private File committedFile;
 
+	private File untrackedFile;
+
 	@Before
 	public void setUp() throws Exception {
 		super.setUp();
@@ -88,16 +90,24 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 		git.add().addFilepattern("file.txt").call();
 		head = git.commit().setMessage("add file").call();
 		assertNotNull(head);
-		writeTrashFile("untracked.txt", "content");
+		untrackedFile = writeTrashFile("untracked.txt", "content");
+	}
+
+	private void validateStashedCommit(final RevCommit commit)
+			throws IOException {
+		validateStashedCommit(commit, 2);
 	}
 
 	/**
 	 * Core validation to be performed on all stashed commits
 	 *
 	 * @param commit
+	 * @param parentCount
+	 *            number of parent commits required
 	 * @throws IOException
 	 */
-	private void validateStashedCommit(final RevCommit commit)
+	private void validateStashedCommit(final RevCommit commit,
+			int parentCount)
 			throws IOException {
 		assertNotNull(commit);
 		Ref stashRef = db.getRef(Constants.R_STASH);
@@ -105,7 +115,7 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 		assertEquals(commit, stashRef.getObjectId());
 		assertNotNull(commit.getAuthorIdent());
 		assertEquals(commit.getAuthorIdent(), commit.getCommitterIdent());
-		assertEquals(2, commit.getParentCount());
+		assertEquals(parentCount, commit.getParentCount());
 
 		// Load parents
 		RevWalk walk = new RevWalk(db);
@@ -461,4 +471,35 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 
 		git.stashCreate().call();
 	}
+
+	@Test
+	public void untrackedFileIncluded() throws Exception {
+		String trackedPath = "tracked.txt";
+		writeTrashFile(trackedPath, "content2");
+		git.add().addFilepattern(trackedPath).call();
+
+		RevCommit stashed = git.stashCreate()
+				.setIncludeUntracked(true).call();
+		validateStashedCommit(stashed, 3);
+
+		assertEquals(
+				"Expected commits for workingDir,stashedIndex and untrackedFiles.",
+				3, stashed.getParentCount());
+		assertFalse("untracked file should be deleted.", untrackedFile.exists());
+	}
+
+	@Test
+	public void untrackedFileNotIncluded() throws Exception {
+		String trackedPath = "tracked.txt";
+		// at least one modification needed
+		writeTrashFile(trackedPath, "content2");
+		git.add().addFilepattern(trackedPath).call();
+
+		RevCommit stashed = git.stashCreate().call();
+		validateStashedCommit(stashed);
+
+		assertTrue("untracked file should be left untouched.",
+				untrackedFile.exists());
+		assertEquals("content", read(untrackedFile));
+	}
 }