Examples with MergeResult org.eclipse.jgit.merge.MergeResult used on opensource projects

Example 1 with MergeResult

use of org.eclipse.jgit.merge.MergeResult in project gerrit by GerritCodeReview.

the class AutoMerger method merge.

/**
   * Perform an auto-merge of the parents of the given merge commit.
   *
   * @return auto-merge commit or {@code null} if an auto-merge commit couldn't be created. Headers
   *     of the returned RevCommit are parsed.
   */
public RevCommit merge(Repository repo, RevWalk rw, final ObjectInserter ins, RevCommit merge, ThreeWayMergeStrategy mergeStrategy) throws IOException {
    checkArgument(rw.getObjectReader().getCreatedFromInserter() == ins);
    InMemoryInserter tmpIns = null;
    if (ins instanceof InMemoryInserter) {
        // Caller gave us an in-memory inserter, so ensure anything we write from
        // this method is visible to them.
        tmpIns = (InMemoryInserter) ins;
    } else if (!save) {
        // If we don't plan on saving results, use a fully in-memory inserter.
        // Using just a non-flushing wrapper is not sufficient, since in
        // particular DfsInserter might try to write to storage after exceeding an
        // internal buffer size.
        tmpIns = new InMemoryInserter(rw.getObjectReader());
    }
    rw.parseHeaders(merge);
    String refName = RefNames.refsCacheAutomerge(merge.name());
    Ref ref = repo.getRefDatabase().exactRef(refName);
    if (ref != null && ref.getObjectId() != null) {
        RevObject obj = rw.parseAny(ref.getObjectId());
        if (obj instanceof RevCommit) {
            return (RevCommit) obj;
        }
        return commit(repo, rw, tmpIns, ins, refName, obj, merge);
    }
    ResolveMerger m = (ResolveMerger) mergeStrategy.newMerger(repo, true);
    DirCache dc = DirCache.newInCore();
    m.setDirCache(dc);
    m.setObjectInserter(tmpIns == null ? new NonFlushingWrapper(ins) : tmpIns);
    boolean couldMerge;
    try {
        couldMerge = m.merge(merge.getParents());
    } catch (IOException e) {
        // It is not safe to continue further down in this method as throwing
        // an exception most likely means that the merge tree was not created
        // and m.getMergeResults() is empty. This would mean that all paths are
        // unmerged and Gerrit UI would show all paths in the patch list.
        log.warn("Error attempting automerge " + refName, e);
        return null;
    }
    ObjectId treeId;
    if (couldMerge) {
        treeId = m.getResultTreeId();
    } else {
        RevCommit ours = merge.getParent(0);
        RevCommit theirs = merge.getParent(1);
        rw.parseBody(ours);
        rw.parseBody(theirs);
        String oursMsg = ours.getShortMessage();
        String theirsMsg = theirs.getShortMessage();
        String oursName = String.format("HEAD   (%s %s)", ours.abbreviate(6).name(), oursMsg.substring(0, Math.min(oursMsg.length(), 60)));
        String theirsName = String.format("BRANCH (%s %s)", theirs.abbreviate(6).name(), theirsMsg.substring(0, Math.min(theirsMsg.length(), 60)));
        MergeFormatter fmt = new MergeFormatter();
        Map<String, MergeResult<? extends Sequence>> r = m.getMergeResults();
        Map<String, ObjectId> resolved = new HashMap<>();
        for (Map.Entry<String, MergeResult<? extends Sequence>> entry : r.entrySet()) {
            MergeResult<? extends Sequence> p = entry.getValue();
            try (TemporaryBuffer buf = new TemporaryBuffer.LocalFile(null, 10 * 1024 * 1024)) {
                fmt.formatMerge(buf, p, "BASE", oursName, theirsName, UTF_8.name());
                buf.close();
                try (InputStream in = buf.openInputStream()) {
                    resolved.put(entry.getKey(), ins.insert(Constants.OBJ_BLOB, buf.length(), in));
                }
            }
        }
        DirCacheBuilder builder = dc.builder();
        int cnt = dc.getEntryCount();
        for (int i = 0; i < cnt; ) {
            DirCacheEntry entry = dc.getEntry(i);
            if (entry.getStage() == 0) {
                builder.add(entry);
                i++;
                continue;
            }
            int next = dc.nextEntry(i);
            String path = entry.getPathString();
            DirCacheEntry res = new DirCacheEntry(path);
            if (resolved.containsKey(path)) {
                // For a file with content merge conflict that we produced a result
                // above on, collapse the file down to a single stage 0 with just
                // the blob content, and a randomly selected mode (the lowest stage,
                // which should be the merge base, or ours).
                res.setFileMode(entry.getFileMode());
                res.setObjectId(resolved.get(path));
            } else if (next == i + 1) {
                // If there is exactly one stage present, shouldn't be a conflict...
                res.setFileMode(entry.getFileMode());
                res.setObjectId(entry.getObjectId());
            } else if (next == i + 2) {
                // Two stages suggests a delete/modify conflict. Pick the higher
                // stage as the automatic result.
                entry = dc.getEntry(i + 1);
                res.setFileMode(entry.getFileMode());
                res.setObjectId(entry.getObjectId());
            } else {
                // 3 stage conflict, no resolve above
                // Punt on the 3-stage conflict and show the base, for now.
                res.setFileMode(entry.getFileMode());
                res.setObjectId(entry.getObjectId());
            }
            builder.add(res);
            i = next;
        }
        builder.finish();
        treeId = dc.writeTree(ins);
    }
    return commit(repo, rw, tmpIns, ins, refName, treeId, merge);
}