Mass assignment is not restricted using attr_accessible Open
class CourseParticipant < Participant
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- Exclude checks
This warning comes up if a model does not limit what attributes can be set through mass assignment.
In particular, this check looks for attr_accessible
inside model definitions. If it is not found, this warning will be issued.
Brakeman also warns on use of attr_protected
- especially since it was found to be vulnerable to bypass. Warnings for mass assignment on models using attr_protected
will be reported, but at a lower confidence level.
Note that disabling mass assignment globally will suppress these warnings.
Assignment Branch Condition size for import is too high. [21.95/15] Open
def self.import(row_hash, _row_header = nil, session, id)
raise ArgumentError, "No user id has been specified." if row_hash.empty?
user = User.find_by(name: row_hash[:name])
if user.nil?
raise ArgumentError, "The record containing #{row_hash[:name]} does not have enough items." if row_hash.length < 4
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- 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
Method import
has a Cognitive Complexity of 7 (exceeds 5 allowed). Consider refactoring. Open
def self.import(row_hash, _row_header = nil, session, id)
raise ArgumentError, "No user id has been specified." if row_hash.empty?
user = User.find_by(name: row_hash[:name])
if user.nil?
raise ArgumentError, "The record containing #{row_hash[:name]} does not have enough items." if row_hash.length < 4
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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
Use find_by
instead of where.first
. Open
part = AssignmentParticipant.where(user_id: self.user_id, parent_id: assignment_id).first
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- Exclude checks
This cop is used to identify usages of where.first
and
change them to use find_by
instead.
Example:
# bad
User.where(name: 'Bruce').first
User.where(name: 'Bruce').take
# good
User.find_by(name: 'Bruce')
Specify an :inverse_of
option. Open
belongs_to :course, class_name: 'Course', foreign_key: 'parent_id'
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- Exclude checks
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 a guard clause instead of wrapping the code inside a conditional expression. Open
unless CourseParticipant.exists?(user_id: user.id, parent_id: id)
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- 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
Favor modifier unless
usage when having a single-line body. Another good alternative is the usage of control flow &&
/||
. Open
unless CourseParticipant.exists?(user_id: user.id, parent_id: id)
- Read upRead up
- Exclude checks
Checks for if and unless statements that would fit on one line
if written as a modifier if/unless. The maximum line length is
configured in the Metrics/LineLength
cop.
Example:
# bad
if condition
do_stuff(bar)
end
unless qux.empty?
Foo.do_something
end
# good
do_stuff(bar) if condition
Foo.do_something unless qux.empty?
Use a guard clause instead of wrapping the code inside a conditional expression. Open
if part.nil?
- 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