renovatebot_renovate/docs/usage/key-concepts/automerge.md

title	description
Automerge configuration and troubleshooting	Learn all about Renovate's automerge functionality here

Introduction

Automerging is a Renovate feature that you can use to automate upgrading dependencies. When enabled, Renovate tries to merge the proposed update once the tests pass.

Keep in mind that Renovate automerges take a bit of time, do not expect Renovate to automerge a PR the second it opens and passes tests. Wait for at least an hour or two before troubleshooting to ensure that Renovate has had the time to run once in a state where tests have passed and the branch is up-to-date with its base branch. If you or others keep committing to the default branch then Renovate cannot find a suitable gap to automerge into!

Once a branch is automerged, the "Git state" needs to be recalculated for every remaining branch. At times, merging one branch could result in another branch's updates being changed or even removed as unnecessary. Renovate's approach is to ensure that automerging branches are up-to-date with their target branch before automerging. This means merging multiple branches in a row won't work reliably, so we prefer not to do that. What all this means is that Renovate will only automerge at most one branch/PR per target branch per run, before you need to wait for the next run.

As a general guide, we recommend that you enable automerge for any type of dependency updates where you would select "merge" anyway. For any updates where you want to review the changelogs - or code - before you merge, you can keep automerge disabled.

Automerge works particularly well for devDependencies as well as for production dependencies in projects which have great test coverage.

For example, if you have Jest or Mocha as a development dependency, and it has an upgrade with passing tests... automerge them! If you have a linter like ESLint or TSLint and its update passes... automerge them! If you have an API with 100% test coverage and Express is updated... automerge it!

{ loading=lazy }

Configuration examples

Automerge lock file maintenance

The lowest risk type of update to automerge is probably lockFileMaintenance. When Renovate performs lock file maintenance, it leaves the project dependency definitions unchanged, but refreshes the lock file completely so that the latest versions according to the package file constraints are installed.

{
  "lockFileMaintenance": {
    "enabled": true,
    "automerge": true
  }
}

Automerge lint tool updates

Automerging lint tool updates can be a real time-saver. Sometimes an update to a lint tool or plugin definition causes tests to fail, and that is usually deliberate/intentional because the lint authors have added a new rule that you need to adhere to. But in many cases the new version(s) will pass tests, and if so then there's really nothing else to consider before merging, so they may as well be automerged:

{
  "packageRules": [
    {
      "matchDepTypes": ["devDependencies"],
      "matchPackageNames": ["lint", "prettier"],
      "automerge": true
    }
  ]
}

Automerge non-major updates

Non-major updates in SemVer ecosystems shouldn't have breaking changes (if they follow the spec), so many users enable automerge for these too:

{
  "packageRules": [
    {
      "matchUpdateTypes": ["minor", "patch"],
      "matchCurrentVersion": "!/^0/",
      "automerge": true
    }
  ]
}

The matchCurrentVersion setting above is a rule to exclude any dependencies which are pre-1.0.0 because those can make breaking changes at any time according to the SemVer spec.

Automerge monorepo PRs

Say you want to automerge patch and minor updates for packages in the group:ionic-nativeMonorepo preset:

{
  "packageRules": [
    {
      "extends": ["monorepo:ionic-native"],
      "matchUpdateTypes": ["patch", "minor"],
      "automerge": true
    }
  ]
}

Faster merges with platform-native automerge

By default, Renovate uses platform-native automerge to speed up automerging. If you don't want Renovate to use the platform-native automerge, then set platformAutomerge to false.

{
  "lockFileMaintenance": {
    "enabled": true,
    "automerge": true,
    "automergeType": "pr",
    "platformAutomerge": false
  }
}

For more information read platformAutomerge.

GitHub Merge Queue

Renovate supports GitHub's Merge Queue.

Read the GitHub Docs, managing a merge queue first.

The steps to enable GitHub's Merge Queue differ based on whether you use GitHub Actions or another CI provider.

!!! tip "GitHub Merge Queue overview page" GitHub has a page that shows all the PRs in the Merge Queue. The page link follows this pattern: https://github.com/organization-name/repository-name/queue/base-branch-name. For example, here's Renovate's main repository's Merge Queue overview.

If you use GitHub Actions

If you use GitHub Actions as your CI provider, follow these steps:

Add the on.merge_group event to your GitHub Action .yaml files, for example:

on:
  pull_request:
  merge_group:

On github.com, go to your repository's "homepage", click on Settings, scroll down to the Pull Requests section and enable the "Allow auto-merge" checkbox.

Then go to your repository's branch protection rules for your base branch (usually main) and enable the "Require merge queue" setting. Confirm you've set the correct "required checks" for your base branch.

Finally, allow Renovate to automerge by setting automerge=true in your Renovate config file, for example:

{
  "packageRules": [
    {
      "description": "Automerge non-major updates",
      "matchUpdateTypes": ["minor", "patch"],
      "automerge": true
    }
  ]
}

If you don't use GitHub Actions

If you don't use GitHub Actions as your CI provider, follow these steps:

Update your CI provider's configuration so it also runs tests on the temporary gh-readonly-queue/{base_branch} branches, read your CI providers's documentation to learn how to do this.

On github.com, go to your repository's "homepage", click on Settings, scroll down to the Pull Requests section and enable the "Allow auto-merge" checkbox. Go to your repository's branch protection rules for your base branch (usually main) and enable the "Require merge queue" setting. Confirm you've set the correct "required checks" for your base branch.

Finally, allow Renovate to automerge by setting automerge=true in your Renovate config file (see earlier example).

Automerging and scheduling

Automerging is particularly beneficial if you have configured a schedule, because Renovate on its own may be able to automerge the majority of your updates. And this is especially so if your repository needs rebasing, like when you use lock files. Let's say you have dependencies abc and xyz with upgrades, and you use a yarn.lock file.

• At the start of the schedule, Renovate will create branches for abc and xyz upgrades, including yarn.lock updates
• After abc passes tests, Renovate will automerge it into the base branch
• The xyz branch has a yarn.lock conflict now
• Renovate will immediately check all other branches and rebase them
• The change to xyz branch will trigger another round of CI tests
• After the updated xyz branch passes, Renovate will automerge it too

This is a lot better than you waking up to two PRs and then having to deal with conflicts yourself after you merge the first one.

Branch vs PR automerging

Even if you automerge PRs, you are likely to still get notification noise - one when the PR is created and another when it is merged. For this reason we recommend you consider setting automergeType=branch which will mean:

• Renovate first creates a branch and no PR
• If tests pass, Renovate pushes a commit directly to the base branch without PR
• If tests fail, Renovate raises a PR for you to review

Add the renovate/** branch to your testing workflow files, or Renovate will not work properly with the automergeType=branch setting.

The result is that passing updates are essentially "silent" - the only sign of them are the commits Renovate pushes to your base branch. If you have enabled branch protection which prevents Renovate from automerging directly to the base branch, then this won't work and you should stick with the default PR-based automerging instead.

Assignees and Reviewers

When automerge is enabled on a PR, Renovate will not add assignees or reviewers at PR creation time, in order to decrease notifications noise a little. If tests subsequently fail, making automerge not possible, then Renovate will add the configured assignees and/or reviewers.

Note: Renovate won't add assignees and reviewers to a PR with failing checks if the PR already has assignees or reviewers present. If there are accounts you wish to ignore (i.e. add assignees and reviewers regardless) then add them to ignoreReviewers to specify those which should be filtered out in such consideration.

Frequent problems and how to resolve them

Automerge not enabled correctly in config

Sometimes, the reason Renovate is not automerging a PR is because of a configuration mistake. You can confirm that Renovate knows you want it to automerge by checking if the PR body includes the text "Automerge: Enabled". If you see "Automerge: Disabled by config" it means you need to make a config change for automerge to work.

Absence of tests

By default, Renovate will not automerge until it sees passing status checks / check runs for the branch. If you have no tests but still want Renovate to automerge, you need to add "ignoreTests": true to your configuration.

!!! tip We strongly recommend you have tests in any project where you are regularly updating dependencies.

Committer restrictions

If you have protected your base branch with a list of allowed committers, and Renovate is not on that list, then naturally automerge can't work.

Pull Requests Required

If you have configured your project to require Pull Requests before merging, it means that branch automerging is not possible, even if Renovate has rights to commit to the base branch.

Required Pull Request reviews

If you have mandatory Pull Request reviews then it means Renovate can't automerge its own PR until such a review has happened.

If you're on github.com or GitHub Enterprise Server (>=3.4) you can let Renovate bypass the mandatory Pull Request reviews using the "Allow specified actors to bypass required pull requests" option in your branch protection rules.

Alternatively, if you use the Mend Renovate App, you can also install the helper apps renovate-approve and renovate-approve-2 and they will mark all automerging Pull Requests by Renovate as approved. These approval helper apps are only available for GitHub.

Codeowners

Depending on the platform, having a CODEOWNERS file could block automerging, because it means a code owner must review the PR.

Overriding global automerge

You might have setup a global configuration in a .github repository, that has a renovate.json file that turns on automerge for certain dependencies. It does not matter where you've put the global config, the important point in this example is that you're extending from a global config that's somewhere else. For this example we'll assume you put your config in a repository on GitHub, called .github.

Repositories in the organization all extend from this global configuration, and so they "inherit" the automerge settings as well.

To turn off automerge for all dependencies of a selected repository, you need to make a config that overrides all packageRules in the repository's renovate.json file, like this:

{
  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
  "extends": ["local>org-name/.github:renovate-config"],
  "packageRules": [
    {
      "matchPackageNames": ["*"],
      "automerge": false
    }
  ]
}