Gemspec

Gemspec/AddRuntimeDependency

Enabled by default Safe Supports autocorrection Version Added Version Changed

Pending

Yes

Always

1.65

-

Prefer add_dependency over add_runtime_dependency as the latter is considered soft-deprecated.

Examples

# bad
Gem::Specification.new do |spec|
  spec.add_runtime_dependency('rubocop')
end

# good
Gem::Specification.new do |spec|
  spec.add_dependency('rubocop')
end

Configurable attributes

Name Default value Configurable values

Include

**/*.gemspec

Array

References

Gemspec/DependencyVersion

Enabled by default Safe Supports autocorrection Version Added Version Changed

Disabled

Yes

No

1.29

-

Enforce that gem dependency version specifications or a commit reference (branch, ref, or tag) are either required or forbidden.

Examples

EnforcedStyle: required (default)

# bad
Gem::Specification.new do |spec|
  spec.add_dependency 'parser'
end

# bad
Gem::Specification.new do |spec|
  spec.add_development_dependency 'parser'
end

# good
Gem::Specification.new do |spec|
  spec.add_dependency 'parser', '>= 2.3.3.1', '< 3.0'
end

# good
Gem::Specification.new do |spec|
  spec.add_development_dependency 'parser', '>= 2.3.3.1', '< 3.0'
end

EnforcedStyle: forbidden

# bad
Gem::Specification.new do |spec|
  spec.add_dependency 'parser', '>= 2.3.3.1', '< 3.0'
end

# bad
Gem::Specification.new do |spec|
  spec.add_development_dependency 'parser', '>= 2.3.3.1', '< 3.0'
end

# good
Gem::Specification.new do |spec|
  spec.add_dependency 'parser'
end

# good
Gem::Specification.new do |spec|
  spec.add_development_dependency 'parser'
end

Configurable attributes

Name Default value Configurable values

EnforcedStyle

required

required, forbidden

Include

**/*.gemspec

Array

AllowedGems

[]

Array

Gemspec/DeprecatedAttributeAssignment

Enabled by default Safe Supports autocorrection Version Added Version Changed

Pending

Yes

Always

1.30

1.40

Checks that deprecated attributes are not set in a gemspec file. Removing deprecated attributes allows the user to receive smaller packed gems.

Examples

# bad
Gem::Specification.new do |spec|
  spec.name = 'your_cool_gem_name'
  spec.test_files = Dir.glob('test/**/*')
end

# bad
Gem::Specification.new do |spec|
  spec.name = 'your_cool_gem_name'
  spec.test_files += Dir.glob('test/**/*')
end

# good
Gem::Specification.new do |spec|
  spec.name = 'your_cool_gem_name'
end

Configurable attributes

Name Default value Configurable values

Severity

warning

String

Include

**/*.gemspec

Array

Gemspec/DevelopmentDependencies

Enabled by default Safe Supports autocorrection Version Added Version Changed

Pending

Yes

No

1.44

-

Enforce that development dependencies for a gem are specified in Gemfile, rather than in the gemspec using add_development_dependency. Alternatively, using EnforcedStyle: gemspec, enforce that all dependencies are specified in gemspec, rather than in Gemfile.

Examples

EnforcedStyle: Gemfile (default)

# Specify runtime dependencies in your gemspec,
# but all other dependencies in your Gemfile.

# bad
# example.gemspec
s.add_development_dependency "foo"

# good
# Gemfile
gem "foo"

# good
# gems.rb
gem "foo"

# good (with AllowedGems: ["bar"])
# example.gemspec
s.add_development_dependency "bar"

EnforcedStyle: gems.rb

# Specify runtime dependencies in your gemspec,
# but all other dependencies in your Gemfile.
#
# Identical to `EnforcedStyle: Gemfile`, but with a different error message.
# Rely on Bundler/GemFilename to enforce the use of `Gemfile` vs `gems.rb`.

# bad
# example.gemspec
s.add_development_dependency "foo"

# good
# Gemfile
gem "foo"

# good
# gems.rb
gem "foo"

# good (with AllowedGems: ["bar"])
# example.gemspec
s.add_development_dependency "bar"

EnforcedStyle: gemspec

# Specify all dependencies in your gemspec.

# bad
# Gemfile
gem "foo"

# good
# example.gemspec
s.add_development_dependency "foo"

# good (with AllowedGems: ["bar"])
# Gemfile
gem "bar"

Configurable attributes

Name Default value Configurable values

EnforcedStyle

Gemfile

Gemfile, gems.rb, gemspec

AllowedGems

[]

Array

Include

**/*.gemspec, **/Gemfile, **/gems.rb

Array

Gemspec/DuplicatedAssignment

Enabled by default Safe Supports autocorrection Version Added Version Changed

Enabled

Yes

No

0.52

1.40

An attribute assignment method calls should be listed only once in a gemspec.

Assigning to an attribute with the same name using spec.foo = will be an unintended usage. On the other hand, duplication of methods such as spec.requirements, spec.add_runtime_dependency, and others are permitted because it is the intended use of appending values.

Examples

# bad
Gem::Specification.new do |spec|
  spec.name = 'rubocop'
  spec.name = 'rubocop2'
end

# good
Gem::Specification.new do |spec|
  spec.name = 'rubocop'
end

# good
Gem::Specification.new do |spec|
  spec.requirements << 'libmagick, v6.0'
  spec.requirements << 'A good graphics card'
end

# good
Gem::Specification.new do |spec|
  spec.add_dependency('parallel', '~> 1.10')
  spec.add_dependency('parser', '>= 2.3.3.1', '< 3.0')
end

Configurable attributes

Name Default value Configurable values

Severity

warning

String

Include

**/*.gemspec

Array

Gemspec/OrderedDependencies

Enabled by default Safe Supports autocorrection Version Added Version Changed

Enabled

Yes

Always

0.51

-

Dependencies in the gemspec should be alphabetically sorted.

Examples

# bad
spec.add_dependency 'rubocop'
spec.add_dependency 'rspec'

# good
spec.add_dependency 'rspec'
spec.add_dependency 'rubocop'

# good
spec.add_dependency 'rubocop'

spec.add_dependency 'rspec'

# bad
spec.add_development_dependency 'rubocop'
spec.add_development_dependency 'rspec'

# good
spec.add_development_dependency 'rspec'
spec.add_development_dependency 'rubocop'

# good
spec.add_development_dependency 'rubocop'

spec.add_development_dependency 'rspec'

# bad
spec.add_runtime_dependency 'rubocop'
spec.add_runtime_dependency 'rspec'

# good
spec.add_runtime_dependency 'rspec'
spec.add_runtime_dependency 'rubocop'

# good
spec.add_runtime_dependency 'rubocop'

spec.add_runtime_dependency 'rspec'

TreatCommentsAsGroupSeparators: true (default)

# good
# For code quality
spec.add_dependency 'rubocop'
# For tests
spec.add_dependency 'rspec'

TreatCommentsAsGroupSeparators: false

# bad
# For code quality
spec.add_dependency 'rubocop'
# For tests
spec.add_dependency 'rspec'

Configurable attributes

Name Default value Configurable values

TreatCommentsAsGroupSeparators

true

Boolean

ConsiderPunctuation

false

Boolean

Include

**/*.gemspec

Array

Gemspec/RequireMFA

Enabled by default Safe Supports autocorrection Version Added Version Changed

Pending

Yes

Always

1.23

1.40

Requires a gemspec to have rubygems_mfa_required metadata set.

This setting tells RubyGems that MFA (Multi-Factor Authentication) is required for accounts to be able perform privileged operations, such as (see RubyGems' documentation for the full list of privileged operations):

  • gem push

  • gem yank

  • gem owner --add/remove

  • adding or removing owners using gem ownership page

This helps make your gem more secure, as users can be more confident that gem updates were pushed by maintainers.

Examples

# bad
Gem::Specification.new do |spec|
  # no `rubygems_mfa_required` metadata specified
end

# good
Gem::Specification.new do |spec|
  spec.metadata = {
    'rubygems_mfa_required' => 'true'
  }
end

# good
Gem::Specification.new do |spec|
  spec.metadata['rubygems_mfa_required'] = 'true'
end

# bad
Gem::Specification.new do |spec|
  spec.metadata = {
    'rubygems_mfa_required' => 'false'
  }
end

# good
Gem::Specification.new do |spec|
  spec.metadata = {
    'rubygems_mfa_required' => 'true'
  }
end

# bad
Gem::Specification.new do |spec|
  spec.metadata['rubygems_mfa_required'] = 'false'
end

# good
Gem::Specification.new do |spec|
  spec.metadata['rubygems_mfa_required'] = 'true'
end

Configurable attributes

Name Default value Configurable values

Severity

warning

String

Include

**/*.gemspec

Array

References

Gemspec/RequiredRubyVersion

Enabled by default Safe Supports autocorrection Version Added Version Changed

Enabled

Yes

No

0.52

1.40

Checks that required_ruby_version in a gemspec file is set to a valid value (non-blank) and matches TargetRubyVersion as set in RuboCop’s configuration for the gem.

This ensures that RuboCop is using the same Ruby version as the gem.

Examples

# When `TargetRubyVersion` of .rubocop.yml is `2.5`.

# bad
Gem::Specification.new do |spec|
  # no `required_ruby_version` specified
end

# bad
Gem::Specification.new do |spec|
  spec.required_ruby_version = '>= 2.4.0'
end

# bad
Gem::Specification.new do |spec|
  spec.required_ruby_version = '>= 2.6.0'
end

# bad
Gem::Specification.new do |spec|
  spec.required_ruby_version = ''
end

# good
Gem::Specification.new do |spec|
  spec.required_ruby_version = '>= 2.5.0'
end

# good
Gem::Specification.new do |spec|
  spec.required_ruby_version = '>= 2.5'
end

# accepted but not recommended
Gem::Specification.new do |spec|
  spec.required_ruby_version = ['>= 2.5.0', '< 2.7.0']
end

# accepted but not recommended, since
# Ruby does not really follow semantic versioning
Gem::Specification.new do |spec|
  spec.required_ruby_version = '~> 2.5'
end

Configurable attributes

Name Default value Configurable values

Severity

warning

String

Include

**/*.gemspec

Array

Gemspec/RubyVersionGlobalsUsage

Enabled by default Safe Supports autocorrection Version Added Version Changed

Enabled

Yes

No

0.72

1.40

Checks that RUBY_VERSION constant is not used in gemspec. Using RUBY_VERSION is dangerous because value of the constant is determined by rake release. It’s possible to have dependency based on ruby version used to execute rake release and not user’s ruby version.

Examples

# bad
Gem::Specification.new do |spec|
  if RUBY_VERSION >= '3.0'
    spec.add_dependency 'gem_a'
  else
    spec.add_dependency 'gem_b'
  end
end

# good
Gem::Specification.new do |spec|
  spec.add_dependency 'gem_a'
end

Configurable attributes

Name Default value Configurable values

Severity

warning

String

Include

**/*.gemspec

Array

References