opendev/gerrit
Code Issues Proposed changes

AutoMerger: Catch RuntimeException from Merger#merge

Browse Source 
Certain merge commits cannot be processed by JGit, in a way that throws
IllegalStateException:

Caused by: java.lang.IllegalStateException: Duplicate stages not allowed: 0 <filename>
        at org.eclipse.jgit.dircache.DirCacheBuilder.bad(DirCacheBuilder.java:277)
        at org.eclipse.jgit.dircache.DirCacheBuilder.resort(DirCacheBuilder.java:267)
        at org.eclipse.jgit.dircache.DirCacheBuilder.finish(DirCacheBuilder.java:223)
        at org.eclipse.jgit.merge.ResolveMerger.mergeTrees(ResolveMerger.java:1041)
        at org.eclipse.jgit.merge.RecursiveMerger.getBaseCommit(RecursiveMerger.java:200)
        at org.eclipse.jgit.merge.RecursiveMerger.getBaseCommit(RecursiveMerger.java:124)
        at org.eclipse.jgit.merge.ThreeWayMerger.mergeBase(ThreeWayMerger.java:133)
        at org.eclipse.jgit.merge.ResolveMerger.mergeImpl(ResolveMerger.java:304)
        at org.eclipse.jgit.merge.Merger.merge(Merger.java:212)
        at org.eclipse.jgit.merge.Merger.merge(Merger.java:165)
        at org.eclipse.jgit.merge.ThreeWayMerger.merge(ThreeWayMerger.java:114)
        at com.google.gerrit.server.patch.AutoMerger.merge(AutoMerger.java:116)
        at com.google.gerrit.server.patch.PatchListLoader.aFor(PatchListLoader.java:388)
        at com.google.gerrit.server.patch.PatchListLoader.readPatchList(PatchListLoader.java:154)
        at com.google.gerrit.server.patch.PatchListLoader.call(PatchListLoader.java:120)
        at com.google.gerrit.server.patch.PatchListLoader.call(PatchListLoader.java:74)

This codepath is called when indexing the change, which depends on the
PatchList. An unchecked exception bubbles up and fails the whole
request, which is a problem when this happens during ReceiveCommits, as
it effectively prevents pushing this change for review. As with other
types of exceptions during PatchListLoader, it's generally preferable to
continue with an incomplete PatchList that contains only the commit
message and merge list, rather than failing the whole operation.

Change-Id: Ib1cdb6ab1ca89e5bf20ae499c7501cc4e0087b85
This commit is contained in:
Dave Borowitz
2018-04-09 04:27:34 -04:00
parent 3817100d4a
commit 29b22dfe05
1 changed files with 1 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
java/com/google/gerrit/server/patch/AutoMerger.java
View File

@@ -114,7 +114,7 @@ public class AutoMerger {
boolean couldMerge;
try {
couldMerge = m.merge(merge.getParents());
} catch (IOException e) {
} catch (IOException | RuntimeException 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