Class Plate
has 51 methods (exceeds 20 allowed). Consider refactoring. Open
class Plate < Labware # rubocop:todo Metrics/ClassLength
include Api::PlateIO::Extensions
include ModelExtensions::Plate
include Transfer::Associations
include Transfer::State::PlateState
File plate.rb
has 320 lines of code (exceeds 250 allowed). Consider refactoring. Open
require 'lab_where_client'
# https://github.com/sanger/sequencescape/raw/master/docs/images/plate.jpg
#
# A plate is a piece of labware made up of a number of {Well wells}. This class represents the physical piece of
Complex method Plate::has_many#construct! (40.6) Open
def construct! # rubocop:todo Metrics/AbcSize
transaction do
plate = proxy_association.owner
plate
.maps
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Flog calculates the ABC score for methods. The ABC score is based on assignments, branches (method calls), and conditions.
You can read more about ABC metrics or the flog tool
Method stock_wells
has a Cognitive Complexity of 10 (exceeds 5 allowed). Consider refactoring. Open
def stock_wells # rubocop:todo Metrics/AbcSize, Metrics/MethodLength
# Optimisation: if the plate is a stock plate then it's wells are it's stock wells!]
if stock_plate?
wells.with_pool_id.index_with { |w| [w] }
else
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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
Complex method Plate#stock_wells (28.0) Open
def stock_wells # rubocop:todo Metrics/AbcSize, Metrics/MethodLength
# Optimisation: if the plate is a stock plate then it's wells are it's stock wells!]
if stock_plate?
wells.with_pool_id.index_with { |w| [w] }
else
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Flog calculates the ABC score for methods. The ABC score is based on assignments, branches (method calls), and conditions.
You can read more about ABC metrics or the flog tool
Plate#construct! refers to 'ids' more than self (maybe move it to another class?) Open
WellAttribute.import(ids.map { |well| { well_id: well } })
Uuid.import(
ids.map { |well| { resource_id: well, resource_type: well_type, external_id: Uuid.generate_uuid } }
)
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Feature Envy occurs when a code fragment references another object more often than it references itself, or when several clients do the same series of manipulations on a particular type of object.
Feature Envy reduces the code's ability to communicate intent: code that "belongs" on one class but which is located in another can be hard to find, and may upset the "System of Names" in the host class.
Feature Envy also affects the design's flexibility: A code fragment that is in the wrong class creates couplings that may not be natural within the application's domain, and creates a loss of cohesion in the unwilling host class.
Feature Envy often arises because it must manipulate other objects (usually its arguments) to get them into a useful form, and one force preventing them (the arguments) doing this themselves is that the common knowledge lives outside the arguments, or the arguments are of too basic a type to justify extending that type. Therefore there must be something which 'knows' about the contents or purposes of the arguments. That thing would have to be more than just a basic type, because the basic types are either containers which don't know about their contents, or they are single objects which can't capture their relationship with their fellows of the same type. So, this thing with the extra knowledge should be reified into a class, and the utility method will most likely belong there.
Example
Running Reek on:
class Warehouse
def sale_price(item)
(item.price - item.rebate) * @vat
end
end
would report:
Warehouse#total_price refers to item more than self (FeatureEnvy)
since this:
(item.price - item.rebate)
belongs to the Item class, not the Warehouse.
Plate#stock_wells contains iterators nested 2 deep Open
storted_stock_wells = w.stock_wells.sort_by { |sw| sw.map.column_order }
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A Nested Iterator
occurs when a block contains another block.
Example
Given
class Duck
class << self
def duck_names
%i!tick trick track!.each do |surname|
%i!duck!.each do |last_name|
puts "full name is #{surname} #{last_name}"
end
end
end
end
end
Reek would report the following warning:
test.rb -- 1 warning:
[5]:Duck#duck_names contains iterators nested 2 deep (NestedIterators)
Plate#update_qc_values_with_parser contains iterators nested 2 deep Open
well_updates.each do |attribute, value|
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A Nested Iterator
occurs when a block contains another block.
Example
Given
class Duck
class << self
def duck_names
%i!tick trick track!.each do |surname|
%i!duck!.each do |last_name|
puts "full name is #{surname} #{last_name}"
end
end
end
end
end
Reek would report the following warning:
test.rb -- 1 warning:
[5]:Duck#duck_names contains iterators nested 2 deep (NestedIterators)
Plate#construct! has approx 13 statements Open
def construct! # rubocop:todo Metrics/AbcSize
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A method with Too Many Statements
is any method that has a large number of lines.
Too Many Statements
warns about any method that has more than 5 statements. Reek's smell detector for Too Many Statements
counts +1 for every simple statement in a method and +1 for every statement within a control structure (if
, else
, case
, when
, for
, while
, until
, begin
, rescue
) but it doesn't count the control structure itself.
So the following method would score +6 in Reek's statement-counting algorithm:
def parse(arg, argv, &error)
if !(val = arg) and (argv.empty? or /\A-/ =~ (val = argv[0]))
return nil, block, nil # +1
end
opt = (val = parse_arg(val, &error))[1] # +2
val = conv_arg(*val) # +3
if opt and !arg
argv.shift # +4
else
val[0] = nil # +5
end
val # +6
end
(You might argue that the two assigments within the first @if@ should count as statements, and that perhaps the nested assignment should count as +2.)
Plate#update_qc_values_with_parser refers to 'parser' more than self (maybe move it to another class?) Open
parser.each_well_and_parameters do |position, well_updates|
# We might have a nil well if a plate was only partially cherrypicked
well = well_hash[position] || next
well_updates.each do |attribute, value|
QcResult.create!(
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Feature Envy occurs when a code fragment references another object more often than it references itself, or when several clients do the same series of manipulations on a particular type of object.
Feature Envy reduces the code's ability to communicate intent: code that "belongs" on one class but which is located in another can be hard to find, and may upset the "System of Names" in the host class.
Feature Envy also affects the design's flexibility: A code fragment that is in the wrong class creates couplings that may not be natural within the application's domain, and creates a loss of cohesion in the unwilling host class.
Feature Envy often arises because it must manipulate other objects (usually its arguments) to get them into a useful form, and one force preventing them (the arguments) doing this themselves is that the common knowledge lives outside the arguments, or the arguments are of too basic a type to justify extending that type. Therefore there must be something which 'knows' about the contents or purposes of the arguments. That thing would have to be more than just a basic type, because the basic types are either containers which don't know about their contents, or they are single objects which can't capture their relationship with their fellows of the same type. So, this thing with the extra knowledge should be reified into a class, and the utility method will most likely belong there.
Example
Running Reek on:
class Warehouse
def sale_price(item)
(item.price - item.rebate) * @vat
end
end
would report:
Warehouse#total_price refers to item more than self (FeatureEnvy)
since this:
(item.price - item.rebate)
belongs to the Item class, not the Warehouse.
Plate#construct! refers to 'plate' more than self (maybe move it to another class?) Open
plate
.maps
.in_row_major_order
.ids
.map { |location_id| { map_id: location_id } }
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Feature Envy occurs when a code fragment references another object more often than it references itself, or when several clients do the same series of manipulations on a particular type of object.
Feature Envy reduces the code's ability to communicate intent: code that "belongs" on one class but which is located in another can be hard to find, and may upset the "System of Names" in the host class.
Feature Envy also affects the design's flexibility: A code fragment that is in the wrong class creates couplings that may not be natural within the application's domain, and creates a loss of cohesion in the unwilling host class.
Feature Envy often arises because it must manipulate other objects (usually its arguments) to get them into a useful form, and one force preventing them (the arguments) doing this themselves is that the common knowledge lives outside the arguments, or the arguments are of too basic a type to justify extending that type. Therefore there must be something which 'knows' about the contents or purposes of the arguments. That thing would have to be more than just a basic type, because the basic types are either containers which don't know about their contents, or they are single objects which can't capture their relationship with their fellows of the same type. So, this thing with the extra knowledge should be reified into a class, and the utility method will most likely belong there.
Example
Running Reek on:
class Warehouse
def sale_price(item)
(item.price - item.rebate) * @vat
end
end
would report:
Warehouse#total_price refers to item more than self (FeatureEnvy)
since this:
(item.price - item.rebate)
belongs to the Item class, not the Warehouse.
Plate#stock_wells has approx 7 statements Open
def stock_wells # rubocop:todo Metrics/AbcSize, Metrics/MethodLength
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A method with Too Many Statements
is any method that has a large number of lines.
Too Many Statements
warns about any method that has more than 5 statements. Reek's smell detector for Too Many Statements
counts +1 for every simple statement in a method and +1 for every statement within a control structure (if
, else
, case
, when
, for
, while
, until
, begin
, rescue
) but it doesn't count the control structure itself.
So the following method would score +6 in Reek's statement-counting algorithm:
def parse(arg, argv, &error)
if !(val = arg) and (argv.empty? or /\A-/ =~ (val = argv[0]))
return nil, block, nil # +1
end
opt = (val = parse_arg(val, &error))[1] # +2
val = conv_arg(*val) # +3
if opt and !arg
argv.shift # +4
else
val[0] = nil # +5
end
val # +6
end
(You might argue that the two assigments within the first @if@ should count as statements, and that perhaps the nested assignment should count as +2.)
Plate#update_qc_values_with_parser has approx 7 statements Open
def update_qc_values_with_parser(parser)
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A method with Too Many Statements
is any method that has a large number of lines.
Too Many Statements
warns about any method that has more than 5 statements. Reek's smell detector for Too Many Statements
counts +1 for every simple statement in a method and +1 for every statement within a control structure (if
, else
, case
, when
, for
, while
, until
, begin
, rescue
) but it doesn't count the control structure itself.
So the following method would score +6 in Reek's statement-counting algorithm:
def parse(arg, argv, &error)
if !(val = arg) and (argv.empty? or /\A-/ =~ (val = argv[0]))
return nil, block, nil # +1
end
opt = (val = parse_arg(val, &error))[1] # +2
val = conv_arg(*val) # +3
if opt and !arg
argv.shift # +4
else
val[0] = nil # +5
end
val # +6
end
(You might argue that the two assigments within the first @if@ should count as statements, and that perhaps the nested assignment should count as +2.)
Plate has at least 48 methods Open
class Plate < Labware # rubocop:todo Metrics/ClassLength
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Too Many Methods
is a special case of LargeClass
.
Example
Given this configuration
TooManyMethods:
max_methods: 3
and this code:
class TooManyMethods
def one; end
def two; end
def three; end
def four; end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[1]:TooManyMethods has at least 4 methods (TooManyMethods)
Plate tests 'wells.loaded?' at least 3 times Open
wells.loaded? ? wells.indexed_by_location[well_name] : wells.located_at_position(well_name).first
end
alias find_well_by_map_description find_well_by_name
def plate_rows
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Repeated Conditional
is a special case of Simulated Polymorphism
. Basically it means you are checking the same value throughout a single class and take decisions based on this.
Example
Given
class RepeatedConditionals
attr_accessor :switch
def repeat_1
puts "Repeat 1!" if switch
end
def repeat_2
puts "Repeat 2!" if switch
end
def repeat_3
puts "Repeat 3!" if switch
end
end
Reek would emit the following warning:
test.rb -- 4 warnings:
[5, 9, 13]:RepeatedConditionals tests switch at least 3 times (RepeatedConditional)
If you get this warning then you are probably not using the right abstraction or even more probable, missing an additional abstraction.
Plate#construct! calls 'ids.map' 2 times Open
WellAttribute.import(ids.map { |well| { well_id: well } })
Uuid.import(
ids.map { |well| { resource_id: well, resource_type: well_type, external_id: Uuid.generate_uuid } }
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Duplication occurs when two fragments of code look nearly identical, or when two fragments of code have nearly identical effects at some conceptual level.
Reek implements a check for Duplicate Method Call.
Example
Here's a very much simplified and contrived example. The following method will report a warning:
def double_thing()
@other.thing + @other.thing
end
One quick approach to silence Reek would be to refactor the code thus:
def double_thing()
thing = @other.thing
thing + thing
end
A slightly different approach would be to replace all calls of double_thing
by calls to @other.double_thing
:
class Other
def double_thing()
thing + thing
end
end
The approach you take will depend on balancing other factors in your code.
Plate#construct! calls 'plate.wells' 2 times Open
plate.wells.import(wells)
ids = plate.wells.ids
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Duplication occurs when two fragments of code look nearly identical, or when two fragments of code have nearly identical effects at some conceptual level.
Reek implements a check for Duplicate Method Call.
Example
Here's a very much simplified and contrived example. The following method will report a warning:
def double_thing()
@other.thing + @other.thing
end
One quick approach to silence Reek would be to refactor the code thus:
def double_thing()
thing = @other.thing
thing + thing
end
A slightly different approach would be to replace all calls of double_thing
by calls to @other.double_thing
:
class Other
def double_thing()
thing + thing
end
end
The approach you take will depend on balancing other factors in your code.
Complex method Plate::search_for_plates (22.6) Open
def self.search_for_plates(params)
with_faculty_sponsor_ids(params[:faculty_sponsor_ids] || nil)
.with_study_id(params[:study_id] || nil)
.with_plate_purpose_ids(params[:plate_purpose_ids] || nil)
.created_between(params[:start_date], params[:end_date])
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Flog calculates the ABC score for methods. The ABC score is based on assignments, branches (method calls), and conditions.
You can read more about ABC metrics or the flog tool
Plate has missing safe method 'construct!' Open
def construct! # rubocop:todo Metrics/AbcSize
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A candidate method for the Missing Safe Method
smell are methods whose names end with an exclamation mark.
An exclamation mark in method names means (the explanation below is taken from here ):
The ! in method names that end with ! means, “This method is dangerous”—or, more precisely, this method is the “dangerous” version of an otherwise equivalent method, with the same name minus the !. “Danger” is relative; the ! doesn’t mean anything at all unless the method name it’s in corresponds to a similar but bang-less method name. So, for example, gsub! is the dangerous version of gsub. exit! is the dangerous version of exit. flatten! is the dangerous version of flatten. And so forth.
Such a method is called Missing Safe Method
if and only if her non-bang version does not exist and this method is reported as a smell.
Example
Given
class C
def foo; end
def foo!; end
def bar!; end
end
Reek would report bar!
as Missing Safe Method
smell but not foo!
.
Reek reports this smell only in a class context, not in a module context in order to allow perfectly legit code like this:
class Parent
def foo; end
end
module Dangerous
def foo!; end
end
class Son < Parent
include Dangerous
end
class Daughter < Parent
end
In this example, Reek would not report the Missing Safe Method
smell for the method foo
of the Dangerous
module.
Plate#stock_plate? performs a nil-check Open
return true if plate_purpose.nil?
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A NilCheck
is a type check. Failures of NilCheck
violate the "tell, don't ask" principle.
Additionally, type checks often mask bigger problems in your source code like not using OOP and / or polymorphism when you should.
Example
Given
class Klass
def nil_checker(argument)
if argument.nil?
puts "argument isn't nil!"
end
end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[3]:Klass#nil_checker performs a nil-check. (NilCheck)
Plate#set_plate_name_and_size performs a nil-check Open
self.size = default_plate_size if size.nil?
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A NilCheck
is a type check. Failures of NilCheck
violate the "tell, don't ask" principle.
Additionally, type checks often mask bigger problems in your source code like not using OOP and / or polymorphism when you should.
Example
Given
class Klass
def nil_checker(argument)
if argument.nil?
puts "argument isn't nil!"
end
end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[3]:Klass#nil_checker performs a nil-check. (NilCheck)
Plate#stock_wells has the variable name 'w' Open
wells.with_pool_id.index_with { |w| [w] }
else
wells
.include_stock_wells
.with_pool_id
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An Uncommunicative Variable Name
is a variable name that doesn't communicate its intent well enough.
Poor names make it hard for the reader to build a mental picture of what's going on in the code. They can also be mis-interpreted; and they hurt the flow of reading, because the reader must slow down to interpret the names.
TODO found Open
# TODO: When on Ruby 2.6 try using endless ranges
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