Complex method Core::Io::Json::Grammar::Intermediate#merge_children_with (30.8) Open
def merge_children_with(node) # rubocop:todo Metrics/AbcSize
(node.children.keys + @children.keys)
.uniq
.each_with_object({}) do |k, store|
cloned =
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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
Core::Io::Json::Grammar::Intermediate#initialize is controlled by argument 'children' Open
@children = children || {}
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Control Parameter
is a special case of Control Couple
Example
A simple example would be the "quoted" parameter in the following method:
def write(quoted)
if quoted
write_quoted @value
else
write_unquoted @value
end
end
Fixing those problems is out of the scope of this document but an easy solution could be to remove the "write" method alltogether and to move the calls to "writequoted" / "writeunquoted" in the initial caller of "write".
Core::Io::Json::Grammar::Resource#resource_details contains iterators nested 2 deep Open
endpoint
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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)
Core::Io::Json::Grammar::Intermediate#merge_children_with has approx 6 statements Open
def merge_children_with(node) # 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.)
Core::Io::Json::Grammar::Root#rooted_json is controlled by argument 'nested' Open
return yield(stream) if nested
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Control Parameter
is a special case of Control Couple
Example
A simple example would be the "quoted" parameter in the following method:
def write(quoted)
if quoted
write_quoted @value
else
write_unquoted @value
end
end
Fixing those problems is out of the scope of this document but an easy solution could be to remove the "write" method alltogether and to move the calls to "writequoted" / "writeunquoted" in the initial caller of "write".
Core::Io::Json::Grammar::Resource#resource_details has 4 parameters Open
def resource_details(endpoint, object, options, stream)
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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::Json::Grammar::Root#object_encoder has approx 6 statements Open
def object_encoder(object, options)
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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.)
Core::Io::Json::Grammar::Resource#resource_details refers to 'stream' more than self (maybe move it to another class?) Open
stream.block('actions') do |nested_stream|
endpoint
.send(:actions, object, options.merge(target: object))
.map { |action, url| nested_stream.attribute(action, url) }
actions(object, options, nested_stream)
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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.
Core::Io::Json::Grammar::Intermediate#merge_children_with calls '@children.key?(k)' 2 times Open
when @children.key?(k) && node.children.key?(k)
node.children[k].merge(@children[k])
when @children.key?(k)
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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.
Core::Io::Json::Grammar::Actions has no descriptive comment Open
class Actions
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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::Json::Grammar::Intermediate#merge_children_with calls 'node.children[k]' 2 times Open
node.children[k].merge(@children[k])
when @children.key?(k)
@children[k]
when node.children.key?(k)
node.children[k]
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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.
Core::Io::Json::Grammar::Leaf has no descriptive comment Open
class Leaf
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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::Json::Grammar::Node has no descriptive comment Open
class Node
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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::Json::Grammar::Intermediate has initialize method Open
module Intermediate
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A module is usually a mixin, so when an #initialize
method is present it is
hard to tell initialization order and parameters so having #initialize
in a module is usually a bad idea.
Example
The Foo
module below contains a method initialize
. Although class B
inherits from A
, the inclusion of Foo
stops A#initialize
from being called.
class A
def initialize(a)
@a = a
end
end
module Foo
def initialize(foo)
@foo = foo
end
end
class B < A
include Foo
def initialize(b)
super('bar')
@b = b
end
end
A simple solution is to rename Foo#initialize
and call that method by name:
module Foo
def setup_foo_module(foo)
@foo = foo
end
end
class B < A
include Foo
def initialize(b)
super 'bar'
setup_foo_module('foo')
@b = b
end
end
Core::Io::Json::Grammar::Intermediate#merge_children_with calls '@children[k]' 2 times Open
node.children[k].merge(@children[k])
when @children.key?(k)
@children[k]
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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.
Core::Io::Json::Grammar::Leaf#merge_children_with calls 'node.children' 2 times Open
raise "Cannot merge as existing leaf node '#{key}'" if node.children.key?(key)
node.children.merge(key => self)
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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.
Core::Io::Json::Grammar::Intermediate#merge_children_with calls 'node.children' 5 times Open
(node.children.keys + @children.keys)
.uniq
.each_with_object({}) do |k, store|
cloned =
case
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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.
Core::Io::Json::Grammar::Resource has no descriptive comment Open
module Resource
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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::Json::Grammar::Root has no descriptive comment Open
class Root
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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::Json::Grammar::Intermediate#merge_children_with calls 'node.children.key?(k)' 2 times Open
when @children.key?(k) && node.children.key?(k)
node.children[k].merge(@children[k])
when @children.key?(k)
@children[k]
when node.children.key?(k)
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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.
Core::Io::Json::Grammar::Intermediate has no descriptive comment Open
module Intermediate
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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::Json::Grammar::Root#object_encoder manually dispatches method call Open
return self unless object.respond_to?(:uuid)
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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::Json::Grammar::Leaf#call performs a nil-check Open
return if o.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)
Core::Io::Json::Grammar::Root takes parameters ['object', 'options'] to 3 methods Open
def encode(object, options)
object_encoder(object, options).call(object, options, options[:stream])
end
# To encode an individual object we use our JSON serialization tree, merged with the actions
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In general, a Data Clump
occurs when the same two or three items frequently appear together in classes and parameter lists, or when a group of instance variable names start or end with similar substrings.
The recurrence of the items often means there is duplicate code spread around to handle them. There may be an abstraction missing from the code, making the system harder to understand.
Example
Given
class Dummy
def x(y1,y2); end
def y(y1,y2); end
def z(y1,y2); end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[2, 3, 4]:Dummy takes parameters [y1, y2] to 3 methods (DataClump)
A possible way to fix this problem (quoting from Martin Fowler):
The first step is to replace data clumps with objects and use the objects whenever you see them. An immediate benefit is that you'll shrink some parameter lists. The interesting stuff happens as you begin to look for behavior to move into the new objects.
Core::Io::Json::Grammar::Leaf#call has the variable name 'k' Open
@attribute_path.inject(object) do |o, k|
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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.
Core::Io::Json::Grammar::Leaf#call has the variable name 'o' Open
@attribute_path.inject(object) do |o, k|
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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.
Core::Io::Json::Grammar::Leaf#dup has the variable name 'p' Open
attribute = @attribute_path.dup.tap { |p| p << @attribute }
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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.
Core::Io::Json::Grammar::Intermediate#merge_children_with has the variable name 'k' Open
.each_with_object({}) do |k, store|
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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.
Core::Io::Json::Grammar::Root#object_encoder has the variable name 'e' Open
rescue Core::Endpoint::BasicHandler::EndpointLookup::MissingEndpoint => e
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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.