I18n::Backend::ActiveRecord::Translation#lookup has approx 6 statements Open
def lookup(keys, *separator)
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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.)
I18n::Backend::ActiveRecord::Translation#value= refers to 'value' more than self (maybe move it to another class?) Open
if value === false
value = FALSY_CHAR
elsif value === true
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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.
I18n::Backend::ActiveRecord::Translation#interpolates? calls 'self.interpolations' 2 times Open
self.interpolations.include?(key) if self.interpolations
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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.
I18n::Backend::ActiveRecord::Translation has no descriptive comment Open
class Translation < ::ActiveRecord::Base
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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
Use the new Ruby 1.9 hash syntax. Open
where(:locale => locale.to_s)
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This cop checks hash literal syntax.
It can enforce either the use of the class hash rocket syntax or the use of the newer Ruby 1.9 syntax (when applicable).
A separate offense is registered for each problematic pair.
The supported styles are:
- ruby19 - forces use of the 1.9 syntax (e.g.
{a: 1}
) when hashes have all symbols for keys - hash_rockets - forces use of hash rockets for all hashes
- nomixedkeys - simply checks for hashes with mixed syntaxes
- ruby19nomixed_keys - forces use of ruby 1.9 syntax and forbids mixed syntax hashes
Example: EnforcedStyle: ruby19 (default)
# bad
{:a => 2}
{b: 1, :c => 2}
# good
{a: 2, b: 1}
{:c => 2, 'd' => 2} # acceptable since 'd' isn't a symbol
{d: 1, 'e' => 2} # technically not forbidden
Example: EnforcedStyle: hash_rockets
# bad
{a: 1, b: 2}
{c: 1, 'd' => 5}
# good
{:a => 1, :b => 2}
Example: EnforcedStyle: nomixedkeys
# bad
{:a => 1, b: 2}
{c: 1, 'd' => 2}
# good
{:a => 1, :b => 2}
{c: 1, d: 2}
Example: EnforcedStyle: ruby19nomixed_keys
# bad
{:a => 1, :b => 2}
{c: 2, 'd' => 3} # should just use hash rockets
# good
{a: 1, b: 2}
{:c => 3, 'd' => 4}
Freeze mutable objects assigned to constants. Open
TRUTHY_CHAR = "\001"
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This cop checks whether some constant value isn't a mutable literal (e.g. array or hash).
Example:
# bad
CONST = [1, 2, 3]
# good
CONST = [1, 2, 3].freeze
# good
CONST = <<~TESTING.freeze
This is a heredoc
TESTING
Align the operands of an expression spanning multiple lines. Open
"You can change the internal separator by overwriting FLATTEN_SEPARATOR."
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This cop checks the indentation of the right hand side operand in binary operations that span more than one line.
Example: EnforcedStyle: aligned (default)
# bad
if a +
b
something
end
# good
if a +
b
something
end
Example: EnforcedStyle: indented
# bad
if a +
b
something
end
# good
if a +
b
something
end
Avoid the use of the case equality operator ===
. Open
if value === false
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This cop checks for uses of the case equality operator(===).
Example:
# bad
Array === something
(1..100) === 7
/something/ === some_string
# good
something.is_a?(Array)
(1..100).include?(7)
some_string =~ /something/
Redundant self
detected. Open
self.interpolations.include?(key) if self.interpolations
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This cop checks for redundant uses of self
.
The usage of self
is only needed when:
Sending a message to same object with zero arguments in presence of a method name clash with an argument or a local variable.
Calling an attribute writer to prevent an local variable assignment.
Note, with using explicit self you can only send messages with public or protected scope, you cannot send private messages this way.
Note we allow uses of self
with operators because it would be awkward
otherwise.
Example:
# bad
def foo(bar)
self.baz
end
# good
def foo(bar)
self.bar # Resolves name clash with the argument.
end
def foo
bar = 1
self.bar # Resolves name clash with the local variable.
end
def foo
%w[x y z].select do |bar|
self.bar == bar # Resolves name clash with argument of the block.
end
end
Use compact module/class definition instead of nested style. Open
module I18n
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This cop checks the style of children definitions at classes and modules. Basically there are two different styles:
Example: EnforcedStyle: nested (default)
# good
# have each child on its own line
class Foo
class Bar
end
end
Example: EnforcedStyle: compact
# good
# combine definitions as much as possible
class Foo::Bar
end
The compact style is only forced for classes/modules with one child.
Redundant self
detected. Open
self.interpolations.include?(key) if self.interpolations
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This cop checks for redundant uses of self
.
The usage of self
is only needed when:
Sending a message to same object with zero arguments in presence of a method name clash with an argument or a local variable.
Calling an attribute writer to prevent an local variable assignment.
Note, with using explicit self you can only send messages with public or protected scope, you cannot send private messages this way.
Note we allow uses of self
with operators because it would be awkward
otherwise.
Example:
# bad
def foo(bar)
self.baz
end
# good
def foo(bar)
self.bar # Resolves name clash with the argument.
end
def foo
bar = 1
self.bar # Resolves name clash with the local variable.
end
def foo
%w[x y z].select do |bar|
self.bar == bar # Resolves name clash with argument of the block.
end
end
Prefer double-quoted strings unless you need single quotes to avoid extra backslashes for escaping. Open
require 'active_record'
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Checks if uses of quotes match the configured preference.
Example: EnforcedStyle: single_quotes (default)
# bad
"No special symbols"
"No string interpolation"
"Just text"
# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"
Example: EnforcedStyle: double_quotes
# bad
'Just some text'
'No special chars or interpolation'
# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"
Prefer double-quoted strings unless you need single quotes to avoid extra backslashes for escaping. Open
self.table_name = 'translations'
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Checks if uses of quotes match the configured preference.
Example: EnforcedStyle: single_quotes (default)
# bad
"No special symbols"
"No string interpolation"
"Just text"
# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"
Example: EnforcedStyle: double_quotes
# bad
'Just some text'
'No special chars or interpolation'
# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"
Avoid the use of the case equality operator ===
. Open
elsif value === true
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This cop checks for uses of the case equality operator(===).
Example:
# bad
Array === something
(1..100) === 7
/something/ === some_string
# good
something.is_a?(Array)
(1..100).include?(7)
some_string =~ /something/
Freeze mutable objects assigned to constants. Open
FALSY_CHAR = "\002"
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This cop checks whether some constant value isn't a mutable literal (e.g. array or hash).
Example:
# bad
CONST = [1, 2, 3]
# good
CONST = [1, 2, 3].freeze
# good
CONST = <<~TESTING.freeze
This is a heredoc
TESTING
Prefer double-quoted strings unless you need single quotes to avoid extra backslashes for escaping. Open
column_name = connection.quote_column_name('key')
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Checks if uses of quotes match the configured preference.
Example: EnforcedStyle: single_quotes (default)
# bad
"No special symbols"
"No string interpolation"
"Just text"
# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"
Example: EnforcedStyle: double_quotes
# bad
'Just some text'
'No special chars or interpolation'
# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"
Missing top-level class documentation comment. Open
class Translation < ::ActiveRecord::Base
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This cop checks for missing top-level documentation of classes and modules. Classes with no body are exempt from the check and so are namespace modules - modules that have nothing in their bodies except classes, other modules, or constant definitions.
The documentation requirement is annulled if the class or module has a "#:nodoc:" comment next to it. Likewise, "#:nodoc: all" does the same for all its children.
Example:
# bad
class Person
# ...
end
# good
# Description/Explanation of Person class
class Person
# ...
end
Use compact module/class definition instead of nested style. Open
class ActiveRecord
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This cop checks the style of children definitions at classes and modules. Basically there are two different styles:
Example: EnforcedStyle: nested (default)
# good
# have each child on its own line
class Foo
class Bar
end
end
Example: EnforcedStyle: compact
# good
# combine definitions as much as possible
class Foo::Bar
end
The compact style is only forced for classes/modules with one child.
Use \
instead of +
or <<
to concatenate those strings. Open
warn "[DEPRECATION] Giving a separator to Translation.lookup is deprecated. " <<
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This cop checks for string literal concatenation at the end of a line.
Example:
# bad
some_str = 'ala' +
'bala'
some_str = 'ala' <<
'bala'
# good
some_str = 'ala' \
'bala'
Use compact module/class definition instead of nested style. Open
module Backend
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This cop checks the style of children definitions at classes and modules. Basically there are two different styles:
Example: EnforcedStyle: nested (default)
# good
# have each child on its own line
class Foo
class Bar
end
end
Example: EnforcedStyle: compact
# good
# combine definitions as much as possible
class Foo::Bar
end
The compact style is only forced for classes/modules with one child.
Pass &:to_s
as an argument to map!
instead of a block. Open
keys = Array(keys).map! { |key| key.to_s }
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Use symbols as procs when possible.
Example:
# bad
something.map { |s| s.upcase }
# good
something.map(&:upcase)