Showing 14 of 14 total issues
RestBaby::Client#body_text is controlled by argument 'type' Open
case type
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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".
RestBaby::Client has at least 6 instance variables Open
class Client
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Too Many Instance Variables
is a special case of LargeClass
.
Example
Given this configuration
TooManyInstanceVariables:
max_instance_variables: 3
and this code:
class TooManyInstanceVariables
def initialize
@arg_1 = :dummy
@arg_2 = :dummy
@arg_3 = :dummy
@arg_4 = :dummy
end
end
Reek would emit the following warning:
test.rb -- 5 warnings:
[1]:TooManyInstanceVariables has at least 4 instance variables (TooManyInstanceVariables)
RestBaby::Client#send_request has approx 9 statements Open
def send_request(uri, request, headers)
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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.)
RestBaby::Client#print_request refers to 'uri' more than self (maybe move it to another class?) Open
query = uri.query == '' ? '' : "?#{uri.query}"
puts ">> REQUEST\n"\
"> URL: #{uri.scheme}://#{uri.host}:#{uri.port}#{uri.path}#{query}\n"\
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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.
Similar blocks of code found in 2 locations. Consider refactoring. Open
def get(headers = {}, path = '', parameters = {})
full_path = [path, URI.encode_www_form(parameters)].join(PARAM_STARTER)
uri = URI.parse("#{@url}#{full_path}")
request = Net::HTTP::Get.new(uri.request_uri)
request.body = nil
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Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 38.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
Similar blocks of code found in 2 locations. Consider refactoring. Open
def delete(headers = {}, path = '', parameters = {})
full_path = [path, URI.encode_www_form(parameters)].join(PARAM_STARTER)
uri = URI.parse("#{@url}#{full_path}")
request = Net::HTTP::Delete.new(uri.request_uri)
request.body = nil
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Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 38.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
RestBaby::Client#print_request calls 'uri.query' 2 times Open
query = uri.query == '' ? '' : "?#{uri.query}"
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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.
RestBaby::Client assumes too much for instance variable '@wsresponse' Open
class Client
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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.
Similar blocks of code found in 2 locations. Consider refactoring. Open
def post(body = nil, headers = {}, path = '')
uri = URI.parse("#{@url}#{path}")
request = Net::HTTP::Post.new(uri.request_uri)
request.body = body
send_request(uri, request, headers)
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Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 30.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
RestBaby::Client#pretty_xml doesn't depend on instance state (maybe move it to another class?) Open
def pretty_xml(xml)
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A Utility Function is any instance method that has no dependency on the state of the instance.
Similar blocks of code found in 2 locations. Consider refactoring. Open
def put(body = nil, headers = {}, path = '')
uri = URI.parse("#{@url}#{path}")
request = Net::HTTP::Put.new(uri.request_uri)
request.body = body
send_request(uri, request, headers)
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Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 30.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
RestBaby::Client takes parameters ['headers', 'path'] to 4 methods Open
def get(headers = {}, path = '', parameters = {})
full_path = [path, URI.encode_www_form(parameters)].join(PARAM_STARTER)
uri = URI.parse("#{@url}#{full_path}")
request = Net::HTTP::Get.new(uri.request_uri)
request.body = nil
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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.
RestBaby::Client#header_text doesn't depend on instance state (maybe move it to another class?) Open
def header_text(message, pointer)
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A Utility Function is any instance method that has no dependency on the state of the instance.
%w
-literals should be delimited by [
and ]
. Open
t.formatters = %w(files offenses)
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This cop enforces the consistent usage of %
-literal delimiters.
Specify the 'default' key to set all preferred delimiters at once. You can continue to specify individual preferred delimiters to override the default.
Example:
# Style/PercentLiteralDelimiters:
# PreferredDelimiters:
# default: '[]'
# '%i': '()'
# good
%w[alpha beta] + %i(gamma delta)
# bad
%W(alpha #{beta})
# bad
%I(alpha beta)