Method change
has a Cognitive Complexity of 21 (exceeds 5 allowed). Consider refactoring. Open
def change
add_index :taggings, :tag_id unless index_exists? :taggings, :tag_id
add_index :taggings, :taggable_id unless index_exists? :taggings, :taggable_id
add_index :taggings, :taggable_type unless index_exists? :taggings, :taggable_type
add_index :taggings, :tagger_id unless index_exists? :taggings, :tagger_id
- Read upRead up
Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Cyclomatic complexity for change is too high. [8/6] Open
def change
add_index :taggings, :tag_id unless index_exists? :taggings, :tag_id
add_index :taggings, :taggable_id unless index_exists? :taggings, :taggable_id
add_index :taggings, :taggable_type unless index_exists? :taggings, :taggable_type
add_index :taggings, :tagger_id unless index_exists? :taggings, :tagger_id
- Read upRead up
- Exclude checks
This cop checks that the cyclomatic complexity of methods is not higher than the configured maximum. The cyclomatic complexity is the number of linearly independent paths through a method. The algorithm counts decision points and adds one.
An if statement (or unless or ?:) increases the complexity by one. An else branch does not, since it doesn't add a decision point. The && operator (or keyword and) can be converted to a nested if statement, and ||/or is shorthand for a sequence of ifs, so they also add one. Loops can be said to have an exit condition, so they add one.
Method has too many lines. [11/10] Open
def change
add_index :taggings, :tag_id unless index_exists? :taggings, :tag_id
add_index :taggings, :taggable_id unless index_exists? :taggings, :taggable_id
add_index :taggings, :taggable_type unless index_exists? :taggings, :taggable_type
add_index :taggings, :tagger_id unless index_exists? :taggings, :tagger_id
- Read upRead up
- Exclude checks
This cop checks if the length of a method exceeds some maximum value. Comment lines can optionally be ignored. The maximum allowed length is configurable.
Perceived complexity for change is too high. [8/7] Open
def change
add_index :taggings, :tag_id unless index_exists? :taggings, :tag_id
add_index :taggings, :taggable_id unless index_exists? :taggings, :taggable_id
add_index :taggings, :taggable_type unless index_exists? :taggings, :taggable_type
add_index :taggings, :tagger_id unless index_exists? :taggings, :tagger_id
- Read upRead up
- Exclude checks
This cop tries to produce a complexity score that's a measure of the
complexity the reader experiences when looking at a method. For that
reason it considers when
nodes as something that doesn't add as much
complexity as an if
or a &&
. Except if it's one of those special
case
/when
constructs where there's no expression after case
. Then
the cop treats it as an if
/elsif
/elsif
... and lets all the when
nodes count. In contrast to the CyclomaticComplexity cop, this cop
considers else
nodes as adding complexity.
Example:
def my_method # 1
if cond # 1
case var # 2 (0.8 + 4 * 0.2, rounded)
when 1 then func_one
when 2 then func_two
when 3 then func_three
when 4..10 then func_other
end
else # 1
do_something until a && b # 2
end # ===
end # 7 complexity points
Assignment Branch Condition size for change is too high. [15.65/15] Open
def change
add_index :taggings, :tag_id unless index_exists? :taggings, :tag_id
add_index :taggings, :taggable_id unless index_exists? :taggings, :taggable_id
add_index :taggings, :taggable_type unless index_exists? :taggings, :taggable_type
add_index :taggings, :tagger_id unless index_exists? :taggings, :tagger_id
- Read upRead up
- Exclude checks
This cop checks that the ABC size of methods is not higher than the configured maximum. The ABC size is based on assignments, branches (method calls), and conditions. See http://c2.com/cgi/wiki?AbcMetric
Use %i
or %I
for an array of symbols. Open
unless index_exists? :taggings, [:tagger_id, :tagger_type]
- Read upRead up
- Exclude checks
This cop can check for array literals made up of symbols that are not using the %i() syntax.
Alternatively, it checks for symbol arrays using the %i() syntax on projects which do not want to use that syntax.
Configuration option: MinSize
If set, arrays with fewer elements than this value will not trigger the
cop. For example, a MinSize of
3` will not enforce a style on an array
of 2 or fewer elements.
Example: EnforcedStyle: percent (default)
# good
%i[foo bar baz]
# bad
[:foo, :bar, :baz]
Example: EnforcedStyle: brackets
# good
[:foo, :bar, :baz]
# bad
%i[foo bar baz]
Line is too long. [86/80] Open
add_index :taggings, :taggable_type unless index_exists? :taggings, :taggable_type
- Exclude checks
Use %i
or %I
for an array of symbols. Open
add_index :taggings, [:taggable_id, :taggable_type, :tagger_id, :context], name: 'taggings_idy'
- Read upRead up
- Exclude checks
This cop can check for array literals made up of symbols that are not using the %i() syntax.
Alternatively, it checks for symbol arrays using the %i() syntax on projects which do not want to use that syntax.
Configuration option: MinSize
If set, arrays with fewer elements than this value will not trigger the
cop. For example, a MinSize of
3` will not enforce a style on an array
of 2 or fewer elements.
Example: EnforcedStyle: percent (default)
# good
%i[foo bar baz]
# bad
[:foo, :bar, :baz]
Example: EnforcedStyle: brackets
# good
[:foo, :bar, :baz]
# bad
%i[foo bar baz]
Use %i
or %I
for an array of symbols. Open
add_index :taggings, [:tagger_id, :tagger_type]
- Read upRead up
- Exclude checks
This cop can check for array literals made up of symbols that are not using the %i() syntax.
Alternatively, it checks for symbol arrays using the %i() syntax on projects which do not want to use that syntax.
Configuration option: MinSize
If set, arrays with fewer elements than this value will not trigger the
cop. For example, a MinSize of
3` will not enforce a style on an array
of 2 or fewer elements.
Example: EnforcedStyle: percent (default)
# good
%i[foo bar baz]
# bad
[:foo, :bar, :baz]
Example: EnforcedStyle: brackets
# good
[:foo, :bar, :baz]
# bad
%i[foo bar baz]
Use %i
or %I
for an array of symbols. Open
unless index_exists? :taggings, [:taggable_id, :taggable_type, :tagger_id, :context], name: 'taggings_idy'
- Read upRead up
- Exclude checks
This cop can check for array literals made up of symbols that are not using the %i() syntax.
Alternatively, it checks for symbol arrays using the %i() syntax on projects which do not want to use that syntax.
Configuration option: MinSize
If set, arrays with fewer elements than this value will not trigger the
cop. For example, a MinSize of
3` will not enforce a style on an array
of 2 or fewer elements.
Example: EnforcedStyle: percent (default)
# good
%i[foo bar baz]
# bad
[:foo, :bar, :baz]
Example: EnforcedStyle: brackets
# good
[:foo, :bar, :baz]
# bad
%i[foo bar baz]
Line is too long. [82/80] Open
add_index :taggings, :taggable_id unless index_exists? :taggings, :taggable_id
- Exclude checks
Missing magic comment # frozen_string_literal: true
. Open
# This migration comes from acts_as_taggable_on_engine (originally 6)
- Read upRead up
- 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
Line is too long. [110/80] Open
unless index_exists? :taggings, [:taggable_id, :taggable_type, :tagger_id, :context], name: 'taggings_idy'
- Exclude checks
Line is too long. [101/80] Open
add_index :taggings, [:taggable_id, :taggable_type, :tagger_id, :context], name: 'taggings_idy'
- Exclude checks
Use a guard clause instead of wrapping the code inside a conditional expression. Open
unless index_exists? :taggings, [:taggable_id, :taggable_type, :tagger_id, :context], name: 'taggings_idy'
- Read upRead up
- Exclude checks
Use a guard clause instead of wrapping the code inside a conditional expression
Example:
# bad
def test
if something
work
end
end
# good
def test
return unless something
work
end
# also good
def test
work if something
end
# bad
if something
raise 'exception'
else
ok
end
# good
raise 'exception' if something
ok