Renovate does not remove and rewrite automergeComment on rebase

[RLRabinowitz]

What Renovate type, platform and version are you using?

Hosted app (not self-hosted), on github.com

Renovate type

• Hosted app
• Self hosted

Renovate platform

• Azure DevOps (dev.azure.com)
• Azure DevOps Server (self-hosted)
• Bitbucket Cloud (bitbucket.org)
• Bitbucket Server (self-hosted)
• Gitea (gitea.com, self-hosted)
• GitHub (github.com, GitHub Enterprise)
• GitLab (gitlab.com, self-hosted)

Describe the bug

According to this PR, if renovate rebases a PR (because of some conflict), it should remove and recreate the automergeComment.
This does not happen in our repository. The comment is created successfully, but the comment isn't removed and recreated on rebase.

The relevant config:

  rebaseWhen: 'conflicted',
  updateLockFiles: true,
  prCreation: 'immediate',
  automergeType: 'pr-comment',
  automergeComment: 'bors r+',

Relevant debug logs

Click me to see logs

DEBUG: PR is conflicted(branch="renovate/node-14.x")
DEBUG: Branch is not mergeable and needs rebasing(branch="renovate/node-14.x")
DEBUG: Using reuseExistingBranch: false(branch="renovate/node-14.x")
DEBUG: manager.getUpdatedPackageFiles() reuseExistinbranch=false(branch="renovate/node-14.x")
DEBUG: npm.updateDependency(): devDependencies.@types/node = 14.14.45(branch="renovate/node-14.x")
DEBUG: Updating @types/node in frontend/package.json(branch="renovate/node-14.x")
DEBUG: npm.updateDependency(): devDependencies.@types/node = 14.14.45(branch="renovate/node-14.x")
DEBUG: Updating @types/node in e2e/package.json(branch="renovate/node-14.x")
DEBUG: npm.updateDependency(): dependencies.@types/node = 14.14.45(branch="renovate/node-14.x")
DEBUG: Updating @types/node in e2e/api-tests/package.json(branch="renovate/node-14.x")
DEBUG: npm.updateDependency(): dependencies.@types/node = 14.14.45(branch="renovate/node-14.x")
DEBUG: Updating @types/node in common/dev/package.json(branch="renovate/node-14.x")
DEBUG: Updated 4 package files(branch="renovate/node-14.x")
DEBUG: Getting updated lock files(branch="renovate/node-14.x")
DEBUG: Writing package.json files(branch="renovate/node-14.x")
... 
<Tons of logs refering to file changes>
...
DEBUG: Committing files to branch renovate/node-14.x(branch="renovate/node-14.x")
DEBUG: git commit(branch="renovate/node-14.x")
{
  "result": {
    "author": null,
    "branch": "renovate/node-14.x",
    "commit": "dfa37ce",
    "root": false,
    "summary": {
      "changes": 7,
      "insertions": 16,
      "deletions": 0
    }
  }
}
DEBUG: git push(branch="renovate/node-14.x")
{
  "result": {
    "pushed": [],
    "branch": {
      "local": "renovate/node-14.x",
      "remote": "renovate/node-14.x",
      "remoteName": "origin"
    },
    "remoteMessages": {
      "all": []
    }
  }
}
INFO: Branch updated(branch="renovate/node-14.x")
{
  "commitSha": "dfa37ce"
}
DEBUG: Checking if we can automerge branch(branch="renovate/node-14.x")
DEBUG: mergeStatus=no automerge(branch="renovate/node-14.x")
DEBUG: Ensuring PR(branch="renovate/node-14.x")
DEBUG: There are 0 errors and 0 warnings(branch="renovate/node-14.x")
DEBUG: Found existing PR(branch="renovate/node-14.x")
DEBUG: getBranchStatus(renovate/node-14.x)(branch="renovate/node-14.x")
DEBUG: Status checks disabled = returning "success"(branch="renovate/node-14.x")
DEBUG: Processing existing PR(branch="renovate/node-14.x")
DEBUG: getBranchStatus(renovate/node-14.x)(branch="renovate/node-14.x")
DEBUG: Status checks disabled = returning "success"(branch="renovate/node-14.x")
DEBUG: getBranchStatus() result(branch="renovate/node-14.x")
{
  "branchStatus": "green",
  "branchName": "renovate/node-14.x"
}
DEBUG: Pull Request #4026 does not need updating(branch="renovate/node-14.x")
DEBUG: PR is configured for automerge(branch="renovate/node-14.x")
DEBUG: PR is conflicted(branch="renovate/node-14.x")

In the end, it exited with PR is conflicted from automerge.ts, so the following lines are never reached:

renovate/lib/workers/pr/automerge.ts

Lines 86 to 96 in e0488a3

	if (rebaseRequested) {
	await platform.ensureCommentRemoval({
	number: pr.number,
	content: automergeComment,
	});
	}
	await platform.ensureComment({
	number: pr.number,
	topic: null,
	content: automergeComment,
	});

Have you created a minimal reproduction repository?

Sorry, but:

• I have provided a minimal reproduction repository
• I don't have time for that, but it happens in a public repository I have linked to
• I don't have time for that, and cannot share my private repository
• The nature of this bug means it's impossible to reproduce publicly

Additional context

The next job resulted in an error, not sure if this is related:

Click me to see logs

INFO: Repository started
{
  "renovateVersion": "25.18.8"
}
DEBUG: Using localDir: /tmp/renovate/gh/env0/env0
DEBUG: Repository cache not found
{
  "cacheFileName": "/tmp/renovate-cache/renovate/repository/github/env0/env0.json"
}
ERROR: Repository has unknown error
{
  "err": {
    "errno": -13,
    "code": "EACCES",
    "syscall": "mkdir",
    "path": "/tmp/renovate-cache/__renovate-private-cache",
    "message": "EACCES: permission denied, mkdir '/tmp/renovate-cache/__renovate-private-cache'",
    "stack": "Error: EACCES: permission denied, mkdir '/tmp/renovate-cache/__renovate-private-cache'"
  }
}
DEBUG: Unknown res
{
  "res": "unknown-error"
}
DEBUG: Repository timing splits (milliseconds)
{
  "splits": {},
  "total": 3
}
INFO: Repository finished
{
  "durationMs": 3
}

[github-actions[bot]]

Hi there,

The Renovate team needs your help! Before we can start work on your issue we first need to know exactly what's causing the current behavior. A minimal reproduction helps us with this.

To get started, please read our guide on minimal reproductions to understand what is needed.

We may close the issue if you have not provided a minimal reproduction within two weeks. If you need more time, or are stuck, please ask for help or more time in a comment.

Good luck,

The Renovate team

[RLRabinowitz]

I have been able to reproduce this.
See https://github.com/RLRabinowitz/renovate-automerge-bug and its README

[github-actions[bot]]

Thank you for providing a reproduction! 🎉 🚀

The Renovate team will take a look at the reproduction repository. Once we confirm the provided repository reproduces the problem, the label will be changed to reproduction:confirmed.

[RLRabinowitz]

Hey there, anyone know if/when a fix for this will be worked on?
@rarkins

[rarkins]

No, unfortunately this is not high in priority compared to other open issues we have, so it would take a community PR to be implemented any time soon

[PhilipAbed]

so you are saying, in case the PR is conflicted, we will never reach the point where we ensureComment?
Per logic i see that if the PR is conflicted then Automerge shouldnt continue, do we really wanna change that logic?

if yes, what should we do in this case just move the comment check above the prConflict? what else?
i'm not sure what to do here