uninitialized constant ActiveRecord::DatabaseConfigurations::ConnectionUrlResolver::URI

使用 Ruby 2.7.2 和 Rails 6.1.3.1，通过 bundle exec rspec 重现该失败。先从 vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations/connection_url_resolver.rb:47 开始，然后从 spec/rails_helper.rb:3 追踪加载过程；当 specs 能够在没有所报告的 NameError 的情况下加载时，即表示完成。

I run my specs on Gitlab CI. When I try to run bundle exec rspec I get:

-----> Running test: bundle exec rspec
An error occurred while loading ./spec/auth/authenticate_user_spec.rb.
Failure/Error: require 'database_cleaner'
NameError:
  uninitialized constant ActiveRecord::DatabaseConfigurations::ConnectionUrlResolver::URI
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations/connection_url_resolver.rb:47:in `uri_parser'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations/connection_url_resolver.rb:25:in `initialize'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations/url_config.rb:48:in `new'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations/url_config.rb:48:in `build_url_hash'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations/url_config.rb:38:in `initialize'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations.rb:262:in `new'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations.rb:262:in `environment_url_config'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations.rb:177:in `build_configs'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/database_configurations.rb:19:in `initialize'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/core.rb:64:in `new'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/core.rb:64:in `configurations='
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/core.rb:66:in `block in <module:Core>'
# ./vendor/bundle/ruby/2.7.0/gems/activesupport-6.1.3.1/lib/active_support/concern.rb:136:in `class_eval'
# ./vendor/bundle/ruby/2.7.0/gems/activesupport-6.1.3.1/lib/active_support/concern.rb:136:in `append_features'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/base.rb:282:in `include'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/base.rb:282:in `<class:Base>'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/base.rb:265:in `<module:ActiveRecord>'
# ./vendor/bundle/ruby/2.7.0/gems/activerecord-6.1.3.1/lib/active_record/base.rb:15:in `<top (required)>'
# ./vendor/bundle/ruby/2.7.0/gems/database_cleaner-active_record-2.0.0/lib/database_cleaner/active_record/truncation.rb:2:in `require'
# ./vendor/bundle/ruby/2.7.0/gems/database_cleaner-active_record-2.0.0/lib/database_cleaner/active_record/truncation.rb:2:in `<top (required)>'
# ./vendor/bundle/ruby/2.7.0/gems/database_cleaner-active_record-2.0.0/lib/database_cleaner/active_record.rb:4:in `require'
# ./vendor/bundle/ruby/2.7.0/gems/database_cleaner-active_record-2.0.0/lib/database_cleaner/active_record.rb:4:in `<top (required)>'
# ./vendor/bundle/ruby/2.7.0/gems/database_cleaner-2.0.1/lib/database_cleaner.rb:1:in `require'
# ./vendor/bundle/ruby/2.7.0/gems/database_cleaner-2.0.1/lib/database_cleaner.rb:1:in `<top (required)>'
# ./spec/rails_helper.rb:3:in `require'
# ./spec/rails_helper.rb:3:in `<top (required)>'
# ./spec/auth/authenticate_user_spec.rb:1:in `require'
# ./spec/auth/authenticate_user_spec.rb:1:in `<top (required)>'
Rails V: 6.1.3.1 - test

ruby '2.7.2'

Gemfile:

group :development, :test do
  gem 'database_cleaner'
end

Gemfile.lock

    database_cleaner (2.0.1)
      database_cleaner-active_record (~> 2.0.0)
    database_cleaner-active_record (2.0.0)
      activerecord (>= 5.a)
      database_cleaner-core (~> 2.0.0)
    database_cleaner-core (2.0.1)

On my internet research I found this:

https://blog.code-fabrik.ch/2021/03/31/sinatra-databaseconfiguration-url.html