Rails 8.1 Support

[comandeo-mongo]

No description provided.

[Copilot]

Pull Request Overview

This PR adds support for Rails 8.1 by updating dependency constraints and test configurations. The changes enable the Mongoid gem to work with Rails 8.1 while maintaining compatibility with earlier versions.

Key Changes:

• Updated activemodel dependency to support versions up to (but not including) 8.2
• Added Rails 8.1 to CI test matrices and re-enabled rails-master testing
• Created a new gemfile for Rails 8.1 testing

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
mongoid.gemspec	Updated activemodel dependency constraint to allow Rails 8.1
gemfiles/rails-8.1.gemfile	Added new gemfile specifying Rails 8.1 dependencies for testing
.github/workflows/test.yml	Updated test matrix to use Rails 8.1 instead of 8.0
.evergreen/config/variants.yml.erb	Re-enabled rails-master variant and added 8.1 to rails-8 matrix
.evergreen/config/axes.yml.erb	Added Rails 8.1 configuration axis definition
.evergreen/config.yml	Added Rails 8.1 axis and updated build variants (mirrors variants.yml.erb changes)

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[jclusso]

Just curious when would you expect this to get merged into the 9.0.8 branch since right now bundling this forces you to downgrade to 9.0.2.

[comandeo-mongo]

@jclusso I am not sure I understand the question. This is merged to 9.0-stable branch, and will be released in the next 9.0.x version, 9.0.9. There is no "9.0.8 branch", actually, this is just a tag for a released version.

[jclusso]

@comandeo-mongo when I bundle from master it forces me to downgrade to 9.0.2

[comandeo-mongo]

This is because we do not update version in master after releases; we should fix this. However, when you install a gem from github directly, you get the latest code of the branch regardless of what the version says.

[johnnyshields]

I've been begging Mongoid for a long time to merge it's release branches back to master... It would help all of us so much if you did this, as the current situation makes it very difficult to track down what change is where--and there have even been cases where changes done on release branches have not been correctly ported back to master.

[jamis]

@jclusso -- you probably want to bundle from the 9.0-stable branch, and not master. Master is technically the 9.1 release branch, but because we haven't yet released 9.1.0 it's all in a kind of uncomfortable limbo.

Dmitry and I will work out the versioning on master so you can bundle it if you need the absolute bleeding edge, but for 99% of cases you'll be better of using the 9.0-stable branch for now.