Gemspec does not have Rails version dependency for various version of the gem

[kiransajeev]

Steps to reproduce

Used version 1.16.0 with Rails 6.0

Got error while checking ability permissions
undefined method `expand_hash_conditions_for_aggregates'

Since this method is deprecated in Rails 6.0, however dependency resolution for the gem passed, It is not in place even for the latest version of the Gem.

Expected behavior

Dependency resolution should fail if a particular version of cancancan gem cannot be used with a specific version of Rails.

For example version 1.16.0 of the gem does not work with Rails 6 however no dependency checks are there in place to prevent using it.

There are following files which are written to support specific version of Rails but it not tagged as dependency

Actual behavior

While trying to install gem version 1.16.0, dependency resolution should fail

System configuration

Rails version:6.0.5

Ruby version:2.7.5

CanCanCan version1.16.0