ViewAttributeMerge

A Ruby gem for merging HTML view attributes with support for Stimulus 2.0 conventions.

• Merges HTML attributes from multiple sources
• Handles and concatenates Stimulus 2.0 data attributes:
  • data-controller
  • data-action
  • data-[controller]-target
• Supports nested data/aria attributes
• Properly concatenates class attributes
• Maintains attribute precedence

Add to your Gemfile:

gem 'view_attribute_merge'

attributes = ViewAttributeMerge.attr_merge(
  { class: "btn", data: { controller: "modal" } },
  { class: "btn-primary", "data-action": "click->modal#open" },
  { "data-modal-target": "dialog" }
)

# Returns:
# {
#   class: ["btn", "btn-primary"],
#   data: {
#     controller: "modal",
#     action: "click->modal#open", 
#     target: "dialog"
#   }
# }

The gem follows Stimulus 2.0 conventions:

• data-controller values are concatenated
• data-action values are concatenated
• data-[controller]-target values are concatenated

# Proper Stimulus 2.0 format:
{ "data-controller": "controller", "data-controller-target": "element" }

# Legacy format (not supported):
{ "data-target": "controller.element" }

After checking out the repo:

1. Run bin/setup to install dependencies
2. Run bundle exec rspec to execute tests
3. Run bundle exec rubocop to check code style
4. Run bundle exec standardrb to verify Standard Ruby style

The project uses:

• Rubocop for linting
• Standard for formatting
• SimpleCov for test coverage (minimum 90%)
• Solargraph for documentation

To generate a coverage report:

COVERAGE=true bundle exec rspec

Open coverage/index.html to view the report.

1. Fork the project
2. Create a feature branch
3. Add tests for your changes
4. Ensure all tests pass and coverage remains at 90%+
5. Submit a pull request

MIT License - see LICENSE.txt