com.google.gerrit.server.submit.RebaseSorter Maven / Gradle / Ivy
// Copyright (C) 2012 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.gerrit.server.submit;
import com.google.common.flogger.FluentLogger;
import com.google.gerrit.entities.BranchNameKey;
import com.google.gerrit.exceptions.StorageException;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.git.CodeReviewCommit;
import com.google.gerrit.server.git.CodeReviewCommit.CodeReviewRevWalk;
import com.google.gerrit.server.query.change.ChangeData;
import com.google.gerrit.server.query.change.InternalChangeQuery;
import com.google.inject.Provider;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevFlag;
public class RebaseSorter {
private static final FluentLogger logger = FluentLogger.forEnclosingClass();
private final CurrentUser caller;
private final CodeReviewRevWalk rw;
private final RevFlag canMergeFlag;
private final RevCommit initialTip;
private final Set alreadyAccepted;
private final Provider queryProvider;
private final Set incoming;
public RebaseSorter(
CurrentUser caller,
CodeReviewRevWalk rw,
RevCommit initialTip,
Set alreadyAccepted,
RevFlag canMergeFlag,
Provider queryProvider,
Set incoming) {
this.caller = caller;
this.rw = rw;
this.canMergeFlag = canMergeFlag;
this.initialTip = initialTip;
this.alreadyAccepted = alreadyAccepted;
this.queryProvider = queryProvider;
this.incoming = incoming;
}
public List sort(Collection toSort) throws IOException {
final List sorted = new ArrayList<>();
final Set sort = new HashSet<>(toSort);
final Set uninterestingParents = new HashSet<>();
while (!sort.isEmpty()) {
final CodeReviewCommit n = removeOne(sort);
collectUninterestingParents(n, uninterestingParents);
rw.resetRetain(canMergeFlag);
rw.markStart(n);
if (initialTip != null) {
rw.markUninteresting(initialTip);
}
CodeReviewCommit c;
final List contents = new ArrayList<>();
while ((c = rw.next()) != null) {
collectUninterestingParents(c, uninterestingParents);
if (!c.has(canMergeFlag) || !incoming.contains(c)) {
if (isMergedInBranchAsSubmittedChange(c, n.change().getDest())
|| isAlreadyMergedInAnyBranch(c)) {
rw.markUninteresting(c);
} else {
// We cannot merge n as it would bring something we
// aren't permitted to merge at this time. Drop n.
//
n.setStatusCode(CommitMergeStatus.MISSING_DEPENDENCY);
n.setStatusMessage(
CommitMergeStatus.createMissingDependencyMessage(
caller, queryProvider, n.name(), c.name()));
}
// Stop RevWalk because c is either a merged commit or a missing
// dependency. Not need to walk further.
break;
}
contents.add(c);
}
if (n.getStatusCode() == CommitMergeStatus.MISSING_DEPENDENCY) {
continue;
}
sort.removeAll(contents);
Collections.reverse(contents);
sorted.removeAll(contents);
sorted.addAll(contents);
}
sorted.removeAll(uninterestingParents);
return sorted;
}
/**
* Rebasing merge commits is done by rebasing their first parent commit, i.e. the first parent is
* updated to the new base while the second parent stays intact. This means for chains of changes
* we only need to rebase changes that are reachable via the first parents. Changes that are
* reachable via second parents do not need to be rebased (since the second parent of merge
* commits stays intact) which is why we filter them out here by marking them as uninteresting.
*/
private void collectUninterestingParents(CodeReviewCommit c, Set uninterestingParents)
throws IOException {
if (c.getParentCount() > 0) {
for (int parent = 1; parent < c.getParentCount(); parent++) {
uninterestingParents.add(c.getParent(parent));
rw.markUninteresting(c.getParent(parent));
}
}
}
private boolean isAlreadyMergedInAnyBranch(CodeReviewCommit commit) throws IOException {
try (CodeReviewRevWalk mirw = CodeReviewCommit.newRevWalk(rw.getObjectReader())) {
mirw.reset();
mirw.markStart(commit);
// check if the commit is merged in other branches
for (RevCommit accepted : alreadyAccepted) {
if (mirw.isMergedInto(mirw.parseCommit(commit), mirw.parseCommit(accepted))) {
logger.atFine().log(
"Dependency %s merged into branch head %s.", commit.getName(), accepted.getName());
return true;
}
}
return false;
} catch (StorageException e) {
throw new IOException(e);
}
}
private boolean isMergedInBranchAsSubmittedChange(CodeReviewCommit commit, BranchNameKey dest) {
List changes = queryProvider.get().byBranchCommit(dest, commit.getId().getName());
for (ChangeData change : changes) {
if (change.change().isMerged()) {
logger.atFine().log(
"Dependency %s associated with merged change %s.", commit.getName(), change.getId());
return true;
}
}
return false;
}
private static T removeOne(Collection c) {
final Iterator i = c.iterator();
final T r = i.next();
i.remove();
return r;
}
}