Complex method Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping (114.9) Open
def generate_json_to_object_mapping(json_to_attribute) # rubocop:todo Metrics/CyclomaticComplexity
code = []
# Split the mappings into two to make things easier. Read only attributes are easily
# handled right now, provided there is not a read_write one that shares their name.
- Read upRead up
- Exclude checks
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 generate_json_to_object_mapping
has a Cognitive Complexity of 21 (exceeds 5 allowed). Consider refactoring. Open
def generate_json_to_object_mapping(json_to_attribute) # rubocop:todo Metrics/CyclomaticComplexity
code = []
# Split the mappings into two to make things easier. Read only attributes are easily
# handled right now, provided there is not a read_write one that shares their name.
- 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
Complex method Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many (45.8) Open
def handle_has_many(attributes, attribute, json, object) # rubocop:todo Metrics/CyclomaticComplexity
if json.first.is_a?(Hash)
uuids = Uuid.include_resource.lookup_many_uuids(json.filter_map { |j| j['uuid'] })
uuid_to_resource = uuids.each_with_object({}) { |uuid, hash| hash[uuid.external_id] = uuid.resource }
mapped_attributes =
- Read upRead up
- Exclude checks
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 generate_json_to_object_mapping
has 62 lines of code (exceeds 25 allowed). Consider refactoring. Open
def generate_json_to_object_mapping(json_to_attribute) # rubocop:todo Metrics/CyclomaticComplexity
code = []
# Split the mappings into two to make things easier. Read only attributes are easily
# handled right now, provided there is not a read_write one that shares their name.
Method handle_has_many
has a Cognitive Complexity of 15 (exceeds 5 allowed). Consider refactoring. Open
def handle_has_many(attributes, attribute, json, object) # rubocop:todo Metrics/CyclomaticComplexity
if json.first.is_a?(Hash)
uuids = Uuid.include_resource.lookup_many_uuids(json.filter_map { |j| j['uuid'] })
uuid_to_resource = uuids.each_with_object({}) { |uuid, hash| hash[uuid.external_id] = uuid.resource }
mapped_attributes =
- 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
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many has 4 parameters Open
def handle_has_many(attributes, attribute, json, object) # rubocop:todo Metrics/CyclomaticComplexity
- Read upRead up
- Exclude checks
A Long Parameter List
occurs when a method has a lot of parameters.
Example
Given
class Dummy
def long_list(foo,bar,baz,fling,flung)
puts foo,bar,baz,fling,flung
end
end
Reek would report the following warning:
test.rb -- 1 warning:
[2]:Dummy#long_list has 5 parameters (LongParameterList)
A common solution to this problem would be the introduction of parameter objects.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_belongs_to has approx 7 statements Open
def handle_belongs_to(attributes, attribute, json, object) # rubocop:todo Metrics/MethodLength
- Read upRead up
- Exclude checks
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.)
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping contains iterators nested 2 deep Open
trunk.inject([model_for_input, []]) do |(model, parts), step|
next_model, next_step =
if model.nil?
[nil, step]
# Brackets here indicate that assignment is intentional and make Rubocop happy
- Read upRead up
- Exclude checks
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)
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many has approx 16 statements Open
def handle_has_many(attributes, attribute, json, object) # rubocop:todo Metrics/CyclomaticComplexity
- Read upRead up
- Exclude checks
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.)
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping has approx 34 statements Open
def generate_json_to_object_mapping(json_to_attribute) # rubocop:todo Metrics/CyclomaticComplexity
- Read upRead up
- Exclude checks
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.)
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_belongs_to refers to 'attributes' more than self (maybe move it to another class?) Open
attributes[attribute] = load_uuid_resource(uuid)
elsif associated.present?
io = ::Core::Io::Registry.instance.lookup_for_class(associated)
attributes[:"#{attribute}_attributes"] = io.map_parameters_to_attributes(json, nil, true)
else
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_belongs_to has 4 parameters Open
def handle_belongs_to(attributes, attribute, json, object) # rubocop:todo Metrics/MethodLength
- Read upRead up
- Exclude checks
A Long Parameter List
occurs when a method has a lot of parameters.
Example
Given
class Dummy
def long_list(foo,bar,baz,fling,flung)
puts foo,bar,baz,fling,flung
end
end
Reek would report the following warning:
test.rb -- 1 warning:
[2]:Dummy#long_list has 5 parameters (LongParameterList)
A common solution to this problem would be the introduction of parameter objects.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many refers to 'json' more than self (maybe move it to another class?) Open
if json.first.is_a?(Hash)
uuids = Uuid.include_resource.lookup_many_uuids(json.filter_map { |j| j['uuid'] })
uuid_to_resource = uuids.each_with_object({}) { |uuid, hash| hash[uuid.external_id] = uuid.resource }
mapped_attributes =
json.map do |j|
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many refers to 'j' more than self (maybe move it to another class?) Open
uuids = Uuid.include_resource.lookup_many_uuids(json.filter_map { |j| j['uuid'] })
uuid_to_resource = uuids.each_with_object({}) { |uuid, hash| hash[uuid.external_id] = uuid.resource }
mapped_attributes =
json.map do |j|
uuid = j.delete('uuid')
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls 'leaf.inspect' 2 times Open
" handle_#{association.macro}(section, #{leaf.inspect}, value, object)"
elsif model.respond_to?(:klass) && (association = model.klass.reflections[leaf])
" handle_#{association.macro}(section, #{leaf.inspect}, value, object)"
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls 'model.reflections' 2 times Open
elsif (association = model.reflections[step])
unless NESTED_SUPPORTING_RELATIONSHIPS.include?(association.macro.to_sym)
raise StandardError, 'Nested attributes only works with belongs_to or has_one'
end
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input has no descriptive comment Open
module Core::Io::Base::JsonFormattingBehaviour::Input
- Read upRead up
- Exclude checks
Classes and modules are the units of reuse and release. It is therefore considered good practice to annotate every class and module with a brief comment outlining its responsibilities.
Example
Given
class Dummy
# Do things...
end
Reek would emit the following warning:
test.rb -- 1 warning:
[1]:Dummy has no descriptive comment (IrresponsibleModule)
Fixing this is simple - just an explaining comment:
# The Dummy class is responsible for ...
class Dummy
# Do things...
end
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls 'model.nil?' 2 times Open
if model.nil?
[nil, step]
# Brackets here indicate that assignment is intentional and make Rubocop happy
elsif (association = model.reflections[step])
unless NESTED_SUPPORTING_RELATIONSHIPS.include?(association.macro.to_sym)
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls 'json.split('.').inspect' 2 times Open
"process_if_present(params, #{json.split('.').inspect}) { |_| raise ReadOnlyAttribute, #{json.inspect} }"
end
)
# Now the harder bit: for attribute we need to work out how we would fill in the attribute
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many calls 'Uuid.include_resource' 2 times Open
uuids = Uuid.include_resource.lookup_many_uuids(json.filter_map { |j| j['uuid'] })
uuid_to_resource = uuids.each_with_object({}) { |uuid, hash| hash[uuid.external_id] = uuid.resource }
mapped_attributes =
json.map do |j|
uuid = j.delete('uuid')
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls 'association.macro' 3 times Open
unless NESTED_SUPPORTING_RELATIONSHIPS.include?(association.macro.to_sym)
raise StandardError, 'Nested attributes only works with belongs_to or has_one'
end
[association.klass, :"#{step}_attributes"]
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many calls 'uuid_to_resource[uuid]' 2 times Open
if uuid_to_resource[uuid]
resource = uuid_to_resource[uuid]
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls ''-' * 30' 2 times Open
low_level(('-' * 30) << name << ('-' * 30))
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls 'json.split('.')' 2 times Open
"process_if_present(params, #{json.split('.').inspect}) { |_| raise ReadOnlyAttribute, #{json.inspect} }"
end
)
# Now the harder bit: for attribute we need to work out how we would fill in the attribute
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping calls ''=' * 30' 2 times Open
low_level(('=' * 30) << name << ('=' * 30))
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#process_if_present manually dispatches method call Open
return unless current.respond_to?(:key?) # Could be nested attribute but not present!
- Read upRead up
- Exclude checks
Reek reports a Manual Dispatch smell if it finds source code that manually checks whether an object responds to a method before that method is called. Manual dispatch is a type of Simulated Polymorphism which leads to code that is harder to reason about, debug, and refactor.
Example
class MyManualDispatcher
attr_reader :foo
def initialize(foo)
@foo = foo
end
def call
foo.bar if foo.respond_to?(:bar)
end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[9]: MyManualDispatcher manually dispatches method call (ManualDispatch)
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many calls '::Core::Io::Registry.instance' 2 times Open
io = ::Core::Io::Registry.instance.lookup_for_object(resource)
else
resource = nil
io = ::Core::Io::Registry.instance.lookup_for_class(association_class(attribute, object))
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling has no descriptive comment Open
module AssociationHandling
- Read upRead up
- Exclude checks
Classes and modules are the units of reuse and release. It is therefore considered good practice to annotate every class and module with a brief comment outlining its responsibilities.
Example
Given
class Dummy
# Do things...
end
Reek would emit the following warning:
test.rb -- 1 warning:
[1]:Dummy has no descriptive comment (IrresponsibleModule)
Fixing this is simple - just an explaining comment:
# The Dummy class is responsible for ...
class Dummy
# Do things...
end
Core::Io::Base::JsonFormattingBehaviour::Input::ReadOnlyAttribute has no descriptive comment Open
class ReadOnlyAttribute < ::Core::Service::Error
- Read upRead up
- Exclude checks
Classes and modules are the units of reuse and release. It is therefore considered good practice to annotate every class and module with a brief comment outlining its responsibilities.
Example
Given
class Dummy
# Do things...
end
Reek would emit the following warning:
test.rb -- 1 warning:
[1]:Dummy has no descriptive comment (IrresponsibleModule)
Fixing this is simple - just an explaining comment:
# The Dummy class is responsible for ...
class Dummy
# Do things...
end
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping manually dispatches method call Open
elsif model.respond_to?(:reflections) && (association = model.reflections[leaf])
" handle_#{association.macro}(section, #{leaf.inspect}, value, object)"
elsif model.respond_to?(:klass) && (association = model.klass.reflections[leaf])
- Read upRead up
- Exclude checks
Reek reports a Manual Dispatch smell if it finds source code that manually checks whether an object responds to a method before that method is called. Manual dispatch is a type of Simulated Polymorphism which leads to code that is harder to reason about, debug, and refactor.
Example
class MyManualDispatcher
attr_reader :foo
def initialize(foo)
@foo = foo
end
def call
foo.bar if foo.respond_to?(:bar)
end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[9]: MyManualDispatcher manually dispatches method call (ManualDispatch)
Method process_if_present
has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring. Open
def process_if_present(json, path)
value =
path.inject(json) do |current, step|
return unless current.respond_to?(:key?) # Could be nested attribute but not present!
return unless current.key?(step)
- 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
Method handle_belongs_to
has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring. Open
def handle_belongs_to(attributes, attribute, json, object) # rubocop:todo Metrics/MethodLength
if json.is_a?(Hash)
uuid = json.delete('uuid')
associated = association_class(attribute, object)
if uuid.present?
- 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
Core::Io::Base::JsonFormattingBehaviour::Input#process_if_present doesn't depend on instance state (maybe move it to another class?) Open
def process_if_present(json, path)
- Read upRead up
- Exclude checks
A Utility Function is any instance method that has no dependency on the state of the instance.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping performs a nil-check Open
read_only, read_write = json_to_attribute.partition { |_, v| v.nil? }
common_keys = read_only.map(&:first) & read_write.map(&:first)
read_only.delete_if { |k, _| common_keys.include?(k) }
code.concat(
read_only.map do |json, _|
- Read upRead up
- Exclude checks
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)
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#load_uuid_resource doesn't depend on instance state (maybe move it to another class?) Open
def load_uuid_resource(uuid)
- Read upRead up
- Exclude checks
A Utility Function is any instance method that has no dependency on the state of the instance.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many performs a nil-check Open
mapped[:delete] = delete unless delete.nil? # Are we deleting this one?
- Read upRead up
- Exclude checks
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)
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping has the variable name 'v' Open
read_only, read_write = json_to_attribute.partition { |_, v| v.nil? }
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input::AssociationHandling#handle_has_many has the variable name 'j' Open
uuids = Uuid.include_resource.lookup_many_uuids(json.filter_map { |j| j['uuid'] })
uuid_to_resource = uuids.each_with_object({}) { |uuid, hash| hash[uuid.external_id] = uuid.resource }
mapped_attributes =
json.map do |j|
- Read upRead up
- Exclude checks
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.
Core::Io::Base::JsonFormattingBehaviour::Input#generate_json_to_object_mapping has the variable name 'k' Open
read_only.delete_if { |k, _| common_keys.include?(k) }
- Read upRead up
- Exclude checks
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.