Add reset with paths support to ResetCommand

Bug: 338701
Change-Id: Id7cbce47131b459e632ddc2c9a94628c7d0b75cd
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

2 files changed, 154 insertions, 8 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java
index 578b98170f..f79592f223 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java
@@ -44,6 +44,7 @@ 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.assertTrue;
 
 import java.io.File;
@@ -58,6 +59,7 @@ import org.eclipse.jgit.api.errors.NoHeadException;
 import org.eclipse.jgit.api.errors.NoMessageException;
 import org.eclipse.jgit.api.errors.WrongRepositoryStateException;
 import org.eclipse.jgit.dircache.DirCache;
+import org.eclipse.jgit.dircache.DirCacheEntry;
 import org.eclipse.jgit.errors.AmbiguousObjectException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
@@ -66,6 +68,7 @@ import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.treewalk.TreeWalk;
 import org.eclipse.jgit.util.FileUtils;
+import org.junit.Assert;
 import org.junit.Test;
 
 public class ResetCommandTest extends RepositoryTestCase {
@@ -74,10 +77,14 @@ public class ResetCommandTest extends RepositoryTestCase {
 
 	private RevCommit initialCommit;
 
+	private RevCommit secondCommit;
+
 	private File indexFile;
 
 	private File untrackedFile;
 
+	private DirCacheEntry prestage;
+
 	public void setupRepository() throws IOException, NoFilepatternException,
 			NoHeadException, NoMessageException, ConcurrentRefUpdateException,
 			JGitInternalException, WrongRepositoryStateException {
@@ -95,7 +102,10 @@ public class ResetCommandTest extends RepositoryTestCase {
 
 		// add file and commit it
 		git.add().addFilepattern("a.txt").call();
-		git.commit().setMessage("adding a.txt").call();
+		secondCommit = git.commit().setMessage("adding a.txt").call();
+
+		prestage = DirCache.read(db.getIndexFile(), db.getFS()).getEntry(
+				indexFile.getName());
 
 		// modify file and add to index
 		writer.print("new content");
@@ -178,6 +188,66 @@ public class ResetCommandTest extends RepositoryTestCase {
 		assertReflog(prevHead, head);
 	}
 
+	@Test
+	public void testPathsReset() throws Exception {
+		setupRepository();
+
+		DirCacheEntry preReset = DirCache.read(db.getIndexFile(), db.getFS())
+				.getEntry(indexFile.getName());
+		assertNotNull(preReset);
+
+		git.add().addFilepattern(untrackedFile.getName()).call();
+
+		// 'a.txt' has already been modified in setupRepository
+		// 'notAddedToIndex.txt' has been added to repository
+		git.reset().addPath(indexFile.getName())
+				.addPath(untrackedFile.getName()).call();
+
+		DirCacheEntry postReset = DirCache.read(db.getIndexFile(), db.getFS())
+				.getEntry(indexFile.getName());
+		assertNotNull(postReset);
+		Assert.assertNotSame(preReset.getObjectId(), postReset.getObjectId());
+		Assert.assertEquals(prestage.getObjectId(), postReset.getObjectId());
+
+		// check that HEAD hasn't moved
+		ObjectId head = db.resolve(Constants.HEAD);
+		assertTrue(head.equals(secondCommit));
+		// check if files still exist
+		assertTrue(untrackedFile.exists());
+		assertTrue(indexFile.exists());
+		assertTrue(inHead(indexFile.getName()));
+		assertTrue(inIndex(indexFile.getName()));
+		assertFalse(inIndex(untrackedFile.getName()));
+	}
+
+	@Test
+	public void testPathsResetWithRef() throws Exception {
+		setupRepository();
+
+		DirCacheEntry preReset = DirCache.read(db.getIndexFile(), db.getFS())
+				.getEntry(indexFile.getName());
+		assertNotNull(preReset);
+
+		git.add().addFilepattern(untrackedFile.getName()).call();
+
+		// 'a.txt' has already been modified in setupRepository
+		// 'notAddedToIndex.txt' has been added to repository
+		// reset to the inital commit
+		git.reset().setRef(initialCommit.getName())
+				.addPath(indexFile.getName())
+				.addPath(untrackedFile.getName()).call();
+
+		// check that HEAD hasn't moved
+		ObjectId head = db.resolve(Constants.HEAD);
+		assertTrue(head.equals(secondCommit));
+		// check if files still exist
+		assertTrue(untrackedFile.exists());
+		assertTrue(indexFile.exists());
+		assertTrue(inHead(indexFile.getName()));
+		assertFalse(inIndex(indexFile.getName()));
+		assertFalse(inIndex(untrackedFile.getName()));
+	}
+
 	private void assertReflog(ObjectId prevHead, ObjectId head)
 			throws IOException {
 		// Check the reflog for HEAD
@@ -187,9 +257,8 @@ public class ResetCommandTest extends RepositoryTestCase {
 		assertEquals(expectedHeadMessage, actualHeadMessage);
 		assertEquals(head.getName(), db.getReflogReader(Constants.HEAD)
 				.getLastEntry().getNewId().getName());
-		assertEquals(prevHead.getName(), db
-				.getReflogReader(Constants.HEAD).getLastEntry().getOldId()
-				.getName());
+		assertEquals(prevHead.getName(), db.getReflogReader(Constants.HEAD)
+				.getLastEntry().getOldId().getName());
 
 		// The reflog for master contains the same as the one for HEAD
 		String actualMasterMessage = db.getReflogReader("refs/heads/master")
@@ -198,9 +267,9 @@ public class ResetCommandTest extends RepositoryTestCase {
 		assertEquals(expectedMasterMessage, actualMasterMessage);
 		assertEquals(head.getName(), db.getReflogReader(Constants.HEAD)
 				.getLastEntry().getNewId().getName());
-		assertEquals(prevHead.getName(),
-				db.getReflogReader("refs/heads/master").getLastEntry()
-						.getOldId().getName());
+		assertEquals(prevHead.getName(), db
+				.getReflogReader("refs/heads/master").getLastEntry().getOldId()
+				.getName());
 	}
 
 	/**
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/ResetCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/ResetCommand.java
index 1ddfd6d77a..206d4062b7 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/ResetCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/ResetCommand.java
@@ -44,12 +44,17 @@ package org.eclipse.jgit.api;
 
 import java.io.IOException;
 import java.text.MessageFormat;
+import java.util.Collection;
+import java.util.LinkedList;
 
 import org.eclipse.jgit.JGitText;
 import org.eclipse.jgit.api.errors.JGitInternalException;
 import org.eclipse.jgit.dircache.DirCache;
 import org.eclipse.jgit.dircache.DirCacheBuilder;
 import org.eclipse.jgit.dircache.DirCacheCheckout;
+import org.eclipse.jgit.dircache.DirCacheEditor;
+import org.eclipse.jgit.dircache.DirCacheEntry;
+import org.eclipse.jgit.dircache.DirCacheIterator;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Ref;
@@ -58,6 +63,9 @@ import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.RepositoryState;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevWalk;
+import org.eclipse.jgit.treewalk.CanonicalTreeParser;
+import org.eclipse.jgit.treewalk.TreeWalk;
+import org.eclipse.jgit.treewalk.filter.PathFilterGroup;
 
 /**
  * A class used to execute a {@code Reset} command. It has setters for all
@@ -103,10 +111,12 @@ public class ResetCommand extends GitCommand<Ref> {
 		KEEP // TODO not implemented yet
 	}
 
-	private String ref;
+	private String ref = Constants.HEAD;
 
 	private ResetType mode;
 
+	private Collection<String> filepaths = new LinkedList<String>();
+
 	/**
 	 *
 	 * @param repo
@@ -157,6 +167,13 @@ public class ResetCommand extends GitCommand<Ref> {
 				rw.release();
 			}
 
+			if (!filepaths.isEmpty()) {
+				// reset [commit] -- paths
+				resetIndexForPaths(commit);
+				setCallable(false);
+				return repo.getRef(Constants.HEAD);
+			}
+
 			// write the ref
 			final RefUpdate ru = repo.updateRef(Constants.HEAD);
 			ru.setNewObjectId(commitId);
@@ -217,10 +234,70 @@ public class ResetCommand extends GitCommand<Ref> {
 	 * @return this instance
 	 */
 	public ResetCommand setMode(ResetType mode) {
+		if (!filepaths.isEmpty())
+			throw new JGitInternalException(MessageFormat.format(
+					JGitText.get().illegalCombinationOfArguments,
+					"[--mixed | --soft | --hard]", "<paths>..."));
 		this.mode = mode;
 		return this;
 	}
 
+	/**
+	 * @param file
+	 *            the file to add
+	 * @return this instance
+	 */
+	public ResetCommand addPath(String file) {
+		if (mode != null)
+			throw new JGitInternalException(MessageFormat.format(
+					JGitText.get().illegalCombinationOfArguments, "<paths>...",
+					"[--mixed | --soft | --hard]"));
+		filepaths.add(file);
+		return this;
+	}
+
+	private void resetIndexForPaths(RevCommit commit) {
+		DirCache dc = null;
+		final DirCacheEditor edit;
+		try {
+			dc = repo.lockDirCache();
+			edit = dc.editor();
+
+			final TreeWalk tw = new TreeWalk(repo);
+			tw.addTree(new DirCacheIterator(dc));
+			tw.addTree(commit.getTree());
+			tw.setFilter(PathFilterGroup.createFromStrings(filepaths));
+
+			while (tw.next()) {
+				final String path = tw.getPathString();
+				// DirCacheIterator dci = tw.getTree(0, DirCacheIterator.class);
+				final CanonicalTreeParser tree = tw.getTree(1,
+						CanonicalTreeParser.class);
+				if (tree == null)
+					// file is not in the commit, remove from index
+					edit.add(new DirCacheEditor.DeletePath(path));
+				else {
+					// revert index to commit
+					edit.add(new DirCacheEditor.PathEdit(path) {
+						@Override
+						public void apply(DirCacheEntry ent) {
+							ent.setFileMode(tree.getEntryFileMode());
+							ent.setObjectId(tree.getEntryObjectId());
+							ent.setLastModified(0);
+						}
+					});
+				}
+			}
+
+			edit.commit();
+		} catch (IOException e) {
+			throw new RuntimeException(e);
+		} finally {
+			if (dc != null)
+				dc.unlock();
+		}
+	}
+
 	private void resetIndex(RevCommit commit) throws IOException {
 		DirCache dc = null;
 		try {