From 7a428fae4bbbb60a76832bbf5185b26605f7270b Mon Sep 17 00:00:00 2001
From: zeripath <art27@cantab.net>
Date: Fri, 29 Jul 2022 00:19:55 +0100
Subject: [PATCH] Ensure that all unmerged files are merged when conflict
checking (#20528)
There is a subtle bug in the code relating to collating the results of
`git ls-files -u -z` in `unmergedFiles()`. The code here makes the
mistake of assuming that every unmerged file will always have a stage 1
conflict, and this results in conflicts that occur in stage 3 only being
dropped.
This PR simply adjusts this code to ensure that any empty unmergedFile
will always be passed down the channel.
The PR also adds a lot of Trace commands to attempt to help find future
bugs in this code.
Fix #19527
Signed-off-by: Andrew Thornton <art27@cantab.net>
---
services/pull/patch.go | 4 +++-
services/pull/patch_unmerged.go | 25 ++++++++++++++++++++++++-
2 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/services/pull/patch.go b/services/pull/patch.go
index bb09acc89f..32895b2e78 100644
--- a/services/pull/patch.go
+++ b/services/pull/patch.go
@@ -124,6 +124,7 @@ func (e *errMergeConflict) Error() string {
}
func attemptMerge(ctx context.Context, file *unmergedFile, tmpBasePath string, gitRepo *git.Repository) error {
+ log.Trace("Attempt to merge:\n%v", file)
switch {
case file.stage1 != nil && (file.stage2 == nil || file.stage3 == nil):
// 1. Deleted in one or both:
@@ -295,7 +296,8 @@ func checkConflicts(ctx context.Context, pr *issues_model.PullRequest, gitRepo *
var treeHash string
treeHash, _, err = git.NewCommand(ctx, "write-tree").RunStdString(&git.RunOpts{Dir: tmpBasePath})
if err != nil {
- return false, err
+ lsfiles, _, _ := git.NewCommand(ctx, "ls-files", "-u").RunStdString(&git.RunOpts{Dir: tmpBasePath})
+ return false, fmt.Errorf("unable to write unconflicted tree: %w\n`git ls-files -u`:\n%s", err, lsfiles)
}
treeHash = strings.TrimSpace(treeHash)
baseTree, err := gitRepo.GetTree("base")
diff --git a/services/pull/patch_unmerged.go b/services/pull/patch_unmerged.go
index 3839419142..465465d0da 100644
--- a/services/pull/patch_unmerged.go
+++ b/services/pull/patch_unmerged.go
@@ -42,6 +42,17 @@ func (line *lsFileLine) SameAs(other *lsFileLine) bool {
line.path == other.path
}
+// String provides a string representation for logging
+func (line *lsFileLine) String() string {
+ if line == nil {
+ return "<nil>"
+ }
+ if line.err != nil {
+ return fmt.Sprintf("%d %s %s %s %v", line.stage, line.mode, line.path, line.sha, line.err)
+ }
+ return fmt.Sprintf("%d %s %s %s", line.stage, line.mode, line.path, line.sha)
+}
+
// readUnmergedLsFileLines calls git ls-files -u -z and parses the lines into mode-sha-stage-path quadruplets
// it will push these to the provided channel closing it at the end
func readUnmergedLsFileLines(ctx context.Context, tmpBasePath string, outputChan chan *lsFileLine) {
@@ -118,6 +129,17 @@ type unmergedFile struct {
err error
}
+// String provides a string representation of the an unmerged file for logging
+func (u *unmergedFile) String() string {
+ if u == nil {
+ return "<nil>"
+ }
+ if u.err != nil {
+ return fmt.Sprintf("error: %v\n%v\n%v\n%v", u.err, u.stage1, u.stage2, u.stage3)
+ }
+ return fmt.Sprintf("%v\n%v\n%v", u.stage1, u.stage2, u.stage3)
+}
+
// unmergedFiles will collate the output from readUnstagedLsFileLines in to file triplets and send them
// to the provided channel, closing at the end.
func unmergedFiles(ctx context.Context, tmpBasePath string, unmerged chan *unmergedFile) {
@@ -138,6 +160,7 @@ func unmergedFiles(ctx context.Context, tmpBasePath string, unmerged chan *unmer
next := &unmergedFile{}
for line := range lsFileLineChan {
+ log.Trace("Got line: %v Current State:\n%v", line, next)
if line.err != nil {
log.Error("Unable to run ls-files -u -z! Error: %v", line.err)
unmerged <- &unmergedFile{err: fmt.Errorf("unable to run ls-files -u -z! Error: %v", line.err)}
@@ -149,7 +172,7 @@ func unmergedFiles(ctx context.Context, tmpBasePath string, unmerged chan *unmer
case 0:
// Should not happen as this represents successfully merged file - we will tolerate and ignore though
case 1:
- if next.stage1 != nil {
+ if next.stage1 != nil || next.stage2 != nil || next.stage3 != nil {
// We need to handle the unstaged file stage1,stage2,stage3
unmerged <- next
}