Assignment Branch Condition size for short_time is too high. [26.32/15] Open
def short_time
result = ''
if start_date && start_date.year == Time.zone.today.year
result += start_date.strftime('%m/%d')
elsif start_date
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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
Method has too many lines. [12/10] Open
def short_time
result = ''
if start_date && start_date.year == Time.zone.today.year
result += start_date.strftime('%m/%d')
elsif start_date
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- 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 short_time is too high. [9/7] Open
def short_time
result = ''
if start_date && start_date.year == Time.zone.today.year
result += start_date.strftime('%m/%d')
elsif start_date
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- 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
Cyclomatic complexity for short_time is too high. [7/6] Open
def short_time
result = ''
if start_date && start_date.year == Time.zone.today.year
result += start_date.strftime('%m/%d')
elsif start_date
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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 short_time
has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring. Open
def short_time
result = ''
if start_date && start_date.year == Time.zone.today.year
result += start_date.strftime('%m/%d')
elsif start_date
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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
Specify an :inverse_of
option. Open
has_many :stickies, -> { current }
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This cop looks for has(one|many) and belongsto associations where
ActiveRecord can't automatically determine the inverse association
because of a scope or the options used. This can result in unnecessary
queries in some circumstances. :inverse_of
must be manually specified
for associations to work in both ways, or set to false
to opt-out.
Example:
# good
class Blog < ApplicationRecord
has_many :posts
end
class Post < ApplicationRecord
belongs_to :blog
end
Example:
# bad
class Blog < ApplicationRecord
has_many :posts, -> { order(published_at: :desc) }
end
class Post < ApplicationRecord
belongs_to :blog
end
# good
class Blog < ApplicationRecord
has_many(:posts,
-> { order(published_at: :desc) },
inverse_of: :blog
)
end
class Post < ApplicationRecord
belongs_to :blog
end
# good
class Blog < ApplicationRecord
with_options inverse_of: :blog do
has_many :posts, -> { order(published_at: :desc) }
end
end
class Post < ApplicationRecord
belongs_to :blog
end
Example:
# bad
class Picture < ApplicationRecord
belongs_to :imageable, polymorphic: true
end
class Employee < ApplicationRecord
has_many :pictures, as: :imageable
end
class Product < ApplicationRecord
has_many :pictures, as: :imageable
end
# good
class Picture < ApplicationRecord
belongs_to :imageable, polymorphic: true
end
class Employee < ApplicationRecord
has_many :pictures, as: :imageable, inverse_of: :imageable
end
class Product < ApplicationRecord
has_many :pictures, as: :imageable, inverse_of: :imageable
end
Example:
# bad
# However, RuboCop can not detect this pattern...
class Physician < ApplicationRecord
has_many :appointments
has_many :patients, through: :appointments
end
class Appointment < ApplicationRecord
belongs_to :physician
belongs_to :patient
end
class Patient < ApplicationRecord
has_many :appointments
has_many :physicians, through: :appointments
end
# good
class Physician < ApplicationRecord
has_many :appointments
has_many :patients, through: :appointments
end
class Appointment < ApplicationRecord
belongs_to :physician, inverse_of: :appointments
belongs_to :patient, inverse_of: :appointments
end
class Patient < ApplicationRecord
has_many :appointments
has_many :physicians, through: :appointments
end
@see http://guides.rubyonrails.org/association_basics.html#bi-directional-associations @see http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html#module-ActiveRecord::Associations::ClassMethods-label-Setting+Inverses
Use %i
or %I
for an array of symbols. Open
validates :name, uniqueness: { scope: [:deleted, :project_id] }
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- 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]
Put include
mixins in separate statements. Open
include Searchable, Deletable, Filterable
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- Exclude checks
This cop checks for grouping of mixins in class
and module
bodies.
By default it enforces mixins to be placed in separate declarations,
but it can be configured to enforce grouping them in one declaration.
Example: EnforcedStyle: separated (default)
# bad
class Foo
include Bar, Qox
end
# good
class Foo
include Qox
include Bar
end
Example: EnforcedStyle: grouped
# bad
class Foo
extend Bar
extend Qox
end
# good
class Foo
extend Qox, Bar
end