/*
* 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
*
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* without modification, are permitted provided that the following
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* - Redistributions in binary form must reproduce the above
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* disclaimer in the documentation and/or other materials provided
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package org.eclipse.jgit.api;
import java.io.File;
import java.io.IOException;
import java.text.MessageFormat;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.api.errors.InvalidRefNameException;
import org.eclipse.jgit.api.errors.JGitInternalException;
import org.eclipse.jgit.api.errors.NoHeadException;
import org.eclipse.jgit.api.errors.WrongRepositoryStateException;
import org.eclipse.jgit.dircache.DirCache;
import org.eclipse.jgit.dircache.DirCacheCheckout;
import org.eclipse.jgit.dircache.DirCacheEditor;
import org.eclipse.jgit.dircache.DirCacheEditor.DeletePath;
import org.eclipse.jgit.dircache.DirCacheEditor.PathEdit;
import org.eclipse.jgit.dircache.DirCacheEntry;
import org.eclipse.jgit.dircache.DirCacheIterator;
import org.eclipse.jgit.errors.CheckoutConflictException;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.lib.RepositoryState;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevTree;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.treewalk.AbstractTreeIterator;
import org.eclipse.jgit.treewalk.CanonicalTreeParser;
import org.eclipse.jgit.treewalk.FileTreeIterator;
import org.eclipse.jgit.treewalk.TreeWalk;
import org.eclipse.jgit.treewalk.filter.TreeFilter;
import org.eclipse.jgit.util.FileUtils;
/**
* Command class to apply a stashed commit.
*
* @see <a href="http://www.kernel.org/pub/software/scm/git/docs/git-stash.html"
* >Git documentation about Stash</a>
* @since 2.0
*/
public class StashApplyCommand extends GitCommand<ObjectId> {
private static final String DEFAULT_REF = Constants.STASH + "@{0}";
/**
* Stash diff filter that looks for differences in the first three trees
* which must be the stash head tree, stash index tree, and stash working
* directory tree in any order.
*/
private static class StashDiffFilter extends TreeFilter {
@Override
public boolean include(final TreeWalk walker) {
final int m = walker.getRawMode(0);
if (walker.getRawMode(1) != m || !walker.idEqual(1, 0))
return true;
if (walker.getRawMode(2) != m || !walker.idEqual(2, 0))
return true;
return false;
}
@Override
public boolean shouldBeRecursive() {
return false;
}
@Override
public TreeFilter clone() {
return this;
}
@Override
public String toString() {
return "STASH_DIFF";
}
}
private String stashRef;
/**
* Create command to apply the changes of a stashed commit
*
* @param repo
*/
public StashApplyCommand(final Repository repo) {
super(repo);
}
/**
* Set the stash reference to apply
* <p>
* This will default to apply the latest stashed commit (stash@{0}) if
* unspecified
*
* @param stashRef
* @return {@code this}
*/
public StashApplyCommand setStashRef(final String stashRef) {
this.stashRef = stashRef;
return this;
}
private boolean isEqualEntry(AbstractTreeIterator iter1,
AbstractTreeIterator iter2) {
if (!iter1.getEntryFileMode().equals(iter2.getEntryFileMode()))
return false;
ObjectId id1 = iter1.getEntryObjectId();
ObjectId id2 = iter2.getEntryObjectId();
return id1 != null ? id1.equals(id2) : id2 == null;
}
/**
* Would unstashing overwrite local changes?
*
* @param stashIndexIter
* @param stashWorkingTreeIter
* @param headIter
* @param indexIter
* @param workingTreeIter
* @return true if unstash conflict, false otherwise
*/
private boolean isConflict(AbstractTreeIterator stashIndexIter,
AbstractTreeIterator stashWorkingTreeIter,
AbstractTreeIterator headIter, AbstractTreeIterator indexIter,
AbstractTreeIterator workingTreeIter) {
// Is the current index dirty?
boolean indexDirty = indexIter != null
&& (headIter == null || !isEqualEntry(indexIter, headIter));
// Is the current working tree dirty?
boolean workingTreeDirty = workingTreeIter != null
&& (headIter == null || !isEqualEntry(workingTreeIter, headIter));
// Would unstashing overwrite existing index changes?
if (indexDirty && stashIndexIter != null && indexIter != null
&& !isEqualEntry(stashIndexIter, indexIter))
return true;
// Would unstashing overwrite existing working tree changes?
if (workingTreeDirty && stashWorkingTreeIter != null
&& workingTreeIter != null
&& !isEqualEntry(stashWorkingTreeIter, workingTreeIter))
return true;
return false;
}
private ObjectId getHeadTree() throws GitAPIException {
final ObjectId headTree;
try {
headTree = repo.resolve(Constants.HEAD + "^{tree}");
} catch (IOException e) {
throw new JGitInternalException(JGitText.get().cannotReadTree, e);
}
if (headTree == null)
throw new NoHeadException(JGitText.get().cannotReadTree);
return headTree;
}
private ObjectId getStashId() throws GitAPIException {
final String revision = stashRef != null ? stashRef : DEFAULT_REF;
final ObjectId stashId;
try {
stashId = repo.resolve(revision);
} catch (IOException e) {
throw new InvalidRefNameException(MessageFormat.format(
JGitText.get().stashResolveFailed, revision), e);
}
if (stashId == null)
throw new InvalidRefNameException(MessageFormat.format(
JGitText.get().stashResolveFailed, revision));
return stashId;
}
private void scanForConflicts(TreeWalk treeWalk) throws IOException {
File workingTree = repo.getWorkTree();
while (treeWalk.next()) {
// State of the stashed index and working directory
AbstractTreeIterator stashIndexIter = treeWalk.getTree(1,
AbstractTreeIterator.class);
AbstractTreeIterator stashWorkingIter = treeWalk.getTree(2,
AbstractTreeIterator.class);
// State of the current HEAD, index, and working directory
AbstractTreeIterator headIter = treeWalk.getTree(3,
AbstractTreeIterator.class);
AbstractTreeIterator indexIter = treeWalk.getTree(4,
AbstractTreeIterator.class);
AbstractTreeIterator workingIter = treeWalk.getTree(5,
AbstractTreeIterator.class);
if (isConflict(stashIndexIter, stashWorkingIter, headIter,
indexIter, workingIter)) {
String path = treeWalk.getPathString();
File file = new File(workingTree, path);
throw new CheckoutConflictException(file.getAbsolutePath());
}
}
}
private void applyChanges(TreeWalk treeWalk, DirCache cache,
DirCacheEditor editor) throws IOException {
File workingTree = repo.getWorkTree();
while (treeWalk.next()) {
String path = treeWalk.getPathString();
File file = new File(workingTree, path);
// State of the stashed HEAD, index, and working directory
AbstractTreeIterator stashHeadIter = treeWalk.getTree(0,
AbstractTreeIterator.class);
AbstractTreeIterator stashIndexIter = treeWalk.getTree(1,
AbstractTreeIterator.class);
AbstractTreeIterator stashWorkingIter = treeWalk.getTree(2,
AbstractTreeIterator.class);
if (stashWorkingIter != null && stashIndexIter != null) {
// Checkout index change
DirCacheEntry entry = cache.getEntry(path);
if (entry == null)
entry = new DirCacheEntry(treeWalk.getRawPath());
entry.setFileMode(stashIndexIter.getEntryFileMode());
entry.setObjectId(stashIndexIter.getEntryObjectId());
DirCacheCheckout.checkoutEntry(repo, file, entry,
treeWalk.getObjectReader());
final DirCacheEntry updatedEntry = entry;
editor.add(new PathEdit(path) {
public void apply(DirCacheEntry ent) {
ent.copyMetaData(updatedEntry);
}
});
// Checkout working directory change
if (!stashWorkingIter.idEqual(stashIndexIter)) {
entry = new DirCacheEntry(treeWalk.getRawPath());
entry.setObjectId(stashWorkingIter.getEntryObjectId());
DirCacheCheckout.checkoutEntry(repo, file, entry,
treeWalk.getObjectReader());
}
} else {
if (stashIndexIter == null
|| (stashHeadIter != null && !stashIndexIter
.idEqual(stashHeadIter)))
editor.add(new DeletePath(path));
FileUtils
.delete(file, FileUtils.RETRY | FileUtils.SKIP_MISSING);
}
}
}
/**
* Apply the changes in a stashed commit to the working directory and index
*
* @return id of stashed commit that was applied
* @throws GitAPIException
* @throws WrongRepositoryStateException
*/
public ObjectId call() throws GitAPIException,
WrongRepositoryStateException {
checkCallable();
if (repo.getRepositoryState() != RepositoryState.SAFE)
throw new WrongRepositoryStateException(MessageFormat.format(
JGitText.get().stashApplyOnUnsafeRepository,
repo.getRepositoryState()));
final ObjectId headTree = getHeadTree();
final ObjectId stashId = getStashId();
ObjectReader reader = repo.newObjectReader();
try {
RevWalk revWalk = new RevWalk(reader);
RevCommit stashCommit = revWalk.parseCommit(stashId);
if (stashCommit.getParentCount() != 2)
throw new JGitInternalException(MessageFormat.format(
JGitText.get().stashCommitMissingTwoParents,
stashId.name()));
RevTree stashWorkingTree = stashCommit.getTree();
RevTree stashIndexTree = revWalk.parseCommit(
stashCommit.getParent(1)).getTree();
RevTree stashHeadTree = revWalk.parseCommit(
stashCommit.getParent(0)).getTree();
CanonicalTreeParser stashWorkingIter = new CanonicalTreeParser();
stashWorkingIter.reset(reader, stashWorkingTree);
CanonicalTreeParser stashIndexIter = new CanonicalTreeParser();
stashIndexIter.reset(reader, stashIndexTree);
CanonicalTreeParser stashHeadIter = new CanonicalTreeParser();
stashHeadIter.reset(reader, stashHeadTree);
CanonicalTreeParser headIter = new CanonicalTreeParser();
headIter.reset(reader, headTree);
DirCache cache = repo.lockDirCache();
DirCacheEditor editor = cache.editor();
try {
DirCacheIterator indexIter = new DirCacheIterator(cache);
FileTreeIterator workingIter = new FileTreeIterator(repo);
TreeWalk treeWalk = new TreeWalk(reader);
treeWalk.setRecursive(true);
treeWalk.setFilter(new StashDiffFilter());
treeWalk.addTree(stashHeadIter);
treeWalk.addTree(stashIndexIter);
treeWalk.addTree(stashWorkingIter);
treeWalk.addTree(headIter);
treeWalk.addTree(indexIter);
treeWalk.addTree(workingIter);
scanForConflicts(treeWalk);
// Reset trees and walk
treeWalk.reset();
stashWorkingIter.reset(reader, stashWorkingTree);
stashIndexIter.reset(reader, stashIndexTree);
stashHeadIter.reset(reader, stashHeadTree);
treeWalk.addTree(stashHeadIter);
treeWalk.addTree(stashIndexIter);
treeWalk.addTree(stashWorkingIter);
applyChanges(treeWalk, cache, editor);
} finally {
editor.commit();
cache.unlock();
}
} catch (JGitInternalException e) {
throw e;
} catch (IOException e) {
throw new JGitInternalException(JGitText.get().stashApplyFailed, e);
} finally {
reader.release();
}
return stashId;
}
}