%w
-literals should be delimited by [
and ]
. Open
AVAILABLE_CATEGORIES = %w(news).freeze
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- Exclude checks
This cop enforces the consistent usage of %
-literal delimiters.
Specify the 'default' key to set all preferred delimiters at once. You can continue to specify individual preferred delimiters to override the default.
Example:
# Style/PercentLiteralDelimiters:
# PreferredDelimiters:
# default: '[]'
# '%i': '()'
# good
%w[alpha beta] + %i(gamma delta)
# bad
%W(alpha #{beta})
# bad
%I(alpha beta)
%w
-literals should be delimited by [
and ]
. Open
VISIBILITY_OPTIONS = %w(public hidden).freeze
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- Exclude checks
This cop enforces the consistent usage of %
-literal delimiters.
Specify the 'default' key to set all preferred delimiters at once. You can continue to specify individual preferred delimiters to override the default.
Example:
# Style/PercentLiteralDelimiters:
# PreferredDelimiters:
# default: '[]'
# '%i': '()'
# good
%w[alpha beta] + %i(gamma delta)
# bad
%W(alpha #{beta})
# bad
%I(alpha beta)
Use invalid_categories.count.positive?
instead of invalid_categories.count > 0
. Open
errors.add(:categories, 'Not all the categories are valid') if invalid_categories.count > 0
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- Exclude checks
This cop checks for usage of comparison operators (==
,
>
, <
) to test numbers as zero, positive, or negative.
These can be replaced by their respective predicate methods.
The cop can also be configured to do the reverse.
The cop disregards #nonzero?
as it its value is truthy or falsey,
but not true
and false
, and thus not always interchangeable with
!= 0
.
The cop ignores comparisons to global variables, since they are often
populated with objects which can be compared with integers, but are
not themselves Interger
polymorphic.
Example: EnforcedStyle: predicate (default)
# bad
foo == 0
0 > foo
bar.baz > 0
# good
foo.zero?
foo.negative?
bar.baz.positive?
Example: EnforcedStyle: comparison
# bad
foo.zero?
foo.negative?
bar.baz.positive?
# good
foo == 0
0 > foo
bar.baz > 0
Missing magic comment # frozen_string_literal: true
. Open
class Post < ApplicationRecord
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- Exclude checks
This cop is designed to help upgrade to Ruby 3.0. It will add the
comment # frozen_string_literal: true
to the top of files to
enable frozen string literals. Frozen string literals may be default
in Ruby 3.0. The comment will be added below a shebang and encoding
comment. The frozen string literal comment is only valid in Ruby 2.3+.
Example: EnforcedStyle: when_needed (default)
# The `when_needed` style will add the frozen string literal comment
# to files only when the `TargetRubyVersion` is set to 2.3+.
# bad
module Foo
# ...
end
# good
# frozen_string_literal: true
module Foo
# ...
end
Example: EnforcedStyle: always
# The `always` style will always add the frozen string literal comment
# to a file, regardless of the Ruby version or if `freeze` or `<<` are
# called on a string literal.
# bad
module Bar
# ...
end
# good
# frozen_string_literal: true
module Bar
# ...
end
Example: EnforcedStyle: never
# The `never` will enforce that the frozen string literal comment does
# not exist in a file.
# bad
# frozen_string_literal: true
module Baz
# ...
end
# good
module Baz
# ...
end
Use safe navigation (&.
) instead of checking if an object exists before calling the method. Open
tags.join(', ') unless tags.nil?
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- Exclude checks
This cop transforms usages of a method call safeguarded by a non nil
check for the variable whose method is being called to
safe navigation (&.
).
Configuration option: ConvertCodeThatCanStartToReturnNil
The default for this is false
. When configured to true
, this will
check for code in the format !foo.nil? && foo.bar
. As it is written,
the return of this code is limited to false
and whatever the return
of the method is. If this is converted to safe navigation,
foo&.bar
can start returning nil
as well as what the method
returns.
Example:
# bad
foo.bar if foo
foo.bar(param1, param2) if foo
foo.bar { |e| e.something } if foo
foo.bar(param) { |e| e.something } if foo
foo.bar if !foo.nil?
foo.bar unless !foo
foo.bar unless foo.nil?
foo && foo.bar
foo && foo.bar(param1, param2)
foo && foo.bar { |e| e.something }
foo && foo.bar(param) { |e| e.something }
# good
foo&.bar
foo&.bar(param1, param2)
foo&.bar { |e| e.something }
foo&.bar(param) { |e| e.something }
foo.nil? || foo.bar
!foo || foo.bar
# Methods that `nil` will `respond_to?` should not be converted to
# use safe navigation
foo.to_i if foo