Feature: Add support for merge commits

[sorenlouv]

• Feature: Improve support for merge commits (Closes Backport commits in PR instead of merge commit #257)
• Fix: Fix bug where backport would fail if no .backportrc.json file existed

[Krzmbrzl]

Okay, I forgot how to make use of this feature and I can't seem to get it working anymore xD

Using the --pr option only seems to backport the first commit of that PR for me. Is there an additional CLI option that is intended for this feature? 🙈

[sorenlouv]

@Krzmbrzl --pr option should be all that's needed. What version are you using? You need minimum 7.2.

As far as I can tell, it works as it should. Take a look at this dummy repo: https://github.com/backport-org/different-merge-strategies. If you clone it, you'll be able to run:

backport --repo backport-org/different-merge-strategies --branch 7.x --pr 9

Then you should see that it backports all commits from the source pull request. I did it here.

I might have missed some edge cases so it would be terrific if you can reproduce the problem in a public repo that I can view.

[Krzmbrzl]

Hm okay. Could it be related to the fact that I was seeing a merge conflict during the cherry-pick of that very first commit? Could that have thrown off the following logic?

I did encounter the issue while trying to backport mumble-voip/mumble#5641 to https://github.com/mumble-voip/mumble/tree/1.4.x, though at commit 3960373d98f9226b73e947abc582e0e4e4ae5936.

The command that I ran was

backport --pr 5641

and then select then 1.4.x branch in the menu presented afterwards.

[sorenlouv]

Hi @Krzmbrzl

Thanks for making me aware of this problem. I just confirmed this is indeed a problem when conflicts occur.

The pull requests is expected to have 8 commits like here. But if a conflict occurs in the first commit, it omits the rest like here.

I'll look into a fix.

[Krzmbrzl]

I just confirmed this is indeed a problem when conflicts occur.

Aha - so it was not me doing something silly - that's good :D

I'll look into a fix.

Thanks! 👍

[sorenlouv]

@Krzmbrzl I've made a fix and released it in v8.4.1. Please let me know if it works for you if you have time.

[Krzmbrzl]

So I've been using the new version for a bit now and while I have yet to use it on a PR that causes a merge conflict, I now constantly keep running into issues where backlog "crashes" and in the logs there is always a message such as

{"level":"error","message":"runSequentially failed Code: 128, Args: \"rev-list -1 --merges e93d486ba6f7504eb08b94befcfc9a07c4fc5aae~1..e93d486ba6f7504eb08b94befcfc9a07c4fc5aae\", Message: fatal: ambiguous argument 'e93d486ba6f7504eb08b94befcfc9a07c4fc5aae~1..e93d486ba6f7504eb08b94befcfc9a07c4fc5aae': unknown revision or path not in the working tree.\nUse '--' to separate paths from revisions, like this:\n'git <command> [<revision>...] -- [<file>...]'","metadata":{"context":{"cmdArgs":["rev-list","-1","--merges","e93d486ba6f7504eb08b94befcfc9a07c4fc5aae~1..e93d486ba6f7504eb08b94befcfc9a07c4fc5aae"],"code":128,"stderr":"fatal: ambiguous argument 'e93d486ba6f7504eb08b94befcfc9a07c4fc5aae~1..e93d486ba6f7504eb08b94befcfc9a07c4fc5aae': unknown revision or path not in the working tree.\nUse '--' to separate paths from revisions, like this:\n'git <command> [<revision>...] -- [<file>...]'\n","stdout":""},"name":"SpawnError","stack":"SpawnError: Code: 128, Args: \"rev-list -1 --merges e93d486ba6f7504eb08b94befcfc9a07c4fc5aae~1..e93d486ba6f7504eb08b94befcfc9a07c4fc5aae\", Message: fatal: ambiguous argument 'e93d486ba6f7504eb08b94befcfc9a07c4fc5aae~1..e93d486ba6f7504eb08b94befcfc9a07c4fc5aae': unknown revision or path not in the working tree.\nUse '--' to separate paths from revisions, like this:\n'git <command> [<revision>...] -- [<file>...]'\n    at ChildProcess.<anonymous> (/usr/local/lib/node_modules/backport/dist/lib/child-process-promisified.js:37:29)\n    at ChildProcess.emit (node:events:526:28)\n    at maybeClose (node:internal/child_process:1092:16)\n    at Process.ChildProcess._handle.onexit (node:internal/child_process:302:5)"},"timestamp":"2022-05-18 09:43:06"}

I'm not sure if this is related to the latest changes though. This is backlog's output when this happens

$ backport --pr 5677
? Select pull request Merge PR #5677: CHANGE(client): Disable RNNoise by default
? Select branch 1.4.x

Backporting to 1.4.x:
✔ Pulling latest changes
An unhandled error occurred while backporting commit. Please see the logs for details

Whenever this happens I have to delete .backport/repositories/<theRepo> and then explicitly fetch the latest commits from the upstream master branch. Then I can repeat above command and it'll work.

[Krzmbrzl]

Note: Just after I wrote this I did encounter a backport with merge conflicts and it seems to work as expected 👍

[sorenlouv]

I now constantly keep running into issues where backlog "crashes"

@Krzmbrzl Thanks for the heads up! I was not aware of this problem until you pointed it out. I have a fixed ready and will merge and release it sometime Thursday.

[sorenlouv]

The fix is released in 8.4.2.

[Krzmbrzl]

Can confirm that everything seems to be working smoothly again. Thank you! 👍