Assignment Branch Condition size for validate is too high. [21.86/15] Open
def validate(value)
return [] if value.nil? && allows_nil?
values = parse_value(value)
if values.length > 1 && !is_flags?
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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. [14/10] Open
def validate(value)
return [] if value.nil? && allows_nil?
values = parse_value(value)
if values.length > 1 && !is_flags?
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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 validate is too high. [8/7] Open
def validate(value)
return [] if value.nil? && allows_nil?
values = parse_value(value)
if values.length > 1 && !is_flags?
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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 validate is too high. [7/6] Open
def validate(value)
return [] if value.nil? && allows_nil?
values = parse_value(value)
if values.length > 1 && !is_flags?
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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.
Complex method FrOData::Properties::Enum#validate (30.1) Open
def validate(value)
return [] if value.nil? && allows_nil?
values = parse_value(value)
if values.length > 1 && !is_flags?
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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
FrOData::Properties::Enum#validate has approx 7 statements Open
def validate(value)
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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.)
Method validate
has a Cognitive Complexity of 7 (exceeds 5 allowed). Consider refactoring. Open
def validate(value)
return [] if value.nil? && allows_nil?
values = parse_value(value)
if values.length > 1 && !is_flags?
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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
FrOData::Properties::Enum assumes too much for instance variable '@value' Open
class Enum < FrOData::Property
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Classes should not assume that instance variables are set or present outside of the current class definition.
Good:
class Foo
def initialize
@bar = :foo
end
def foo?
@bar == :foo
end
end
Good as well:
class Foo
def foo?
bar == :foo
end
def bar
@bar ||= :foo
end
end
Bad:
class Foo
def go_foo!
@bar = :foo
end
def foo?
@bar == :foo
end
end
Example
Running Reek on:
class Dummy
def test
@ivar
end
end
would report:
[1]:InstanceVariableAssumption: Dummy assumes too much for instance variable @ivar
Note that this example would trigger this smell warning as well:
class Parent
def initialize(omg)
@omg = omg
end
end
class Child < Parent
def foo
@omg
end
end
The way to address the smell warning is that you should create an attr_reader
to use @omg
in the subclass and not access @omg
directly like this:
class Parent
attr_reader :omg
def initialize(omg)
@omg = omg
end
end
class Child < Parent
def foo
omg
end
end
Directly accessing instance variables is considered a smell because it breaks encapsulation and makes it harder to reason about code.
If you don't want to expose those methods as public API just make them private like this:
class Parent
def initialize(omg)
@omg = omg
end
private
attr_reader :omg
end
class Child < Parent
def foo
omg
end
end
Current Support in Reek
An instance variable must:
- be set in the constructor
- or be accessed through a method with lazy initialization / memoization.
If not, Instance Variable Assumption will be reported.
FrOData::Properties::Enum#parse_value performs a nil-check Open
return nil if value.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)
FrOData::Properties::Enum#parse_value doesn't depend on instance state (maybe move it to another class?) Open
def parse_value(value)
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A Utility Function is any instance method that has no dependency on the state of the instance.
FrOData::Properties::Enum#validate performs a nil-check Open
return [] if value.nil? && allows_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)
FrOData::Properties::Enum#value performs a nil-check Open
if @value.nil? && allows_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)
Shadowing outer local variable - value
. Open
values.map do |value|
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This cop looks for use of the same name as outer local variables
for block arguments or block local variables.
This is a mimic of the warning
"shadowing outer local variable - foo" from ruby -cw
.
Example:
# bad
def some_method
foo = 1
2.times do |foo| # shadowing outer `foo`
do_something(foo)
end
end
Example:
# good
def some_method
foo = 1
2.times do |bar|
do_something(bar)
end
end
Line is too long. [82/80] Open
raise ArgumentError, 'Multiple values are not allowed for this property'
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Line is too long. [88/80] Open
validation_error "Value must be one of #{members.to_a}, but was: '#{value}'"
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