Users::OmniauthCallbacksController assumes too much for instance variable '@user' Open
class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
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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.
Users::OmniauthCallbacksController has no descriptive comment Open
class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
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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
Users::OmniauthCallbacksController#google_oauth2 has the name 'google_oauth2' Open
def google_oauth2
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An Uncommunicative Method Name
is a method 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.
Use 2 (not 4) spaces for indentation. Open
@user = User.from_omniauth(request.env['omniauth.auth'], current_user)
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Checks for indentation that doesn't use the specified number of spaces.
See also the IndentationConsistency cop which is the companion to this one.
Example:
# bad
class A
def test
puts 'hello'
end
end
# good
class A
def test
puts 'hello'
end
end
Example: AllowedPatterns: ['^\s*module']
# bad
module A
class B
def test
puts 'hello'
end
end
end
# good
module A
class B
def test
puts 'hello'
end
end
end
Missing top-level documentation comment for class Users::OmniauthCallbacksController
. Open
class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
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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, constant definitions or constant visibility declarations.
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
module Math
end
# good
# Description/Explanation of Person class
class Person
# ...
end
# allowed
# Class without body
class Person
end
# Namespace - A namespace can be a class or a module
# Containing a class
module Namespace
# Description/Explanation of Person class
class Person
# ...
end
end
# Containing constant visibility declaration
module Namespace
class Private
end
private_constant :Private
end
# Containing constant definition
module Namespace
Public = Class.new
end
# Macro calls
module Namespace
extend Foo
end
Example: AllowedConstants: ['ClassMethods']
# good
module A
module ClassMethods
# ...
end
end
Use nested module/class definitions instead of compact style. Open
class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
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Checks the style of children definitions at classes and modules. Basically there are two different styles:
Safety:
Autocorrection is unsafe.
Moving from compact to nested children requires knowledge of whether the outer parent is a module or a class. Moving from nested to compact requires verification that the outer parent is defined elsewhere. RuboCop does not have the knowledge to perform either operation safely and thus requires manual oversight.
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 the new Ruby 1.9 hash syntax. Open
flash[:notice] = I18n.t 'devise.omniauth_callbacks.success', :kind => 'Google'
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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
This cop has EnforcedShorthandSyntax
option.
It can enforce either the use of the explicit hash value syntax or
the use of Ruby 3.1's hash value shorthand syntax.
The supported styles are:
- always - forces use of the 3.1 syntax (e.g. {foo:})
- never - forces use of explicit hash literal value
- either - accepts both shorthand and explicit use of hash literal value
- consistent - forces use of the 3.1 syntax only if all values can be omitted in the hash
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}
Example: EnforcedShorthandSyntax: always (default)
# bad
{foo: foo, bar: bar}
# good
{foo:, bar:}
Example: EnforcedShorthandSyntax: never
# bad
{foo:, bar:}
# good
{foo: foo, bar: bar}
Example: EnforcedShorthandSyntax: either
# good
{foo: foo, bar: bar}
# good
{foo: foo, bar:}
# good
{foo:, bar:}
Example: EnforcedShorthandSyntax: consistent
# bad - `foo` and `bar` values can be omitted
{foo: foo, bar: bar}
# bad - `bar` value can be omitted
{foo:, bar: bar}
# bad - mixed syntaxes
{foo:, bar: baz}
# good
{foo:, bar:}
# good - can't omit `baz`
{foo: foo, bar: baz}
Use the new Ruby 1.9 hash syntax. Open
sign_in_and_redirect @user, :event => :authentication
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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
This cop has EnforcedShorthandSyntax
option.
It can enforce either the use of the explicit hash value syntax or
the use of Ruby 3.1's hash value shorthand syntax.
The supported styles are:
- always - forces use of the 3.1 syntax (e.g. {foo:})
- never - forces use of explicit hash literal value
- either - accepts both shorthand and explicit use of hash literal value
- consistent - forces use of the 3.1 syntax only if all values can be omitted in the hash
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}
Example: EnforcedShorthandSyntax: always (default)
# bad
{foo: foo, bar: bar}
# good
{foo:, bar:}
Example: EnforcedShorthandSyntax: never
# bad
{foo:, bar:}
# good
{foo: foo, bar: bar}
Example: EnforcedShorthandSyntax: either
# good
{foo: foo, bar: bar}
# good
{foo: foo, bar:}
# good
{foo:, bar:}
Example: EnforcedShorthandSyntax: consistent
# bad - `foo` and `bar` values can be omitted
{foo: foo, bar: bar}
# bad - `bar` value can be omitted
{foo:, bar: bar}
# bad - mixed syntaxes
{foo:, bar: baz}
# good
{foo:, bar:}
# good - can't omit `baz`
{foo: foo, bar: baz}
Final newline missing. Open
end
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Looks for trailing blank lines and a final newline in the source code.
Example: EnforcedStyle: final_newline (default)
# `final_newline` looks for one newline at the end of files.
# bad
class Foo; end
# EOF
# bad
class Foo; end # EOF
# good
class Foo; end
# EOF
Example: EnforcedStyle: finalblankline
# `final_blank_line` looks for one blank line followed by a new line
# at the end of files.
# bad
class Foo; end
# EOF
# bad
class Foo; end # EOF
# good
class Foo; end
# EOF
Missing frozen string literal comment. Open
class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
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Helps you transition from mutable string literals
to frozen string literals.
It will add the # frozen_string_literal: true
magic comment to the top
of files to enable frozen string literals. Frozen string literals may be
default in future Ruby. The comment will be added below a shebang and
encoding comment. The frozen string literal comment is only valid in Ruby 2.3+.
Note that the cop will accept files where the comment exists but is set
to false
instead of true
.
To require a blank line after this comment, please see
Layout/EmptyLineAfterMagicComment
cop.
Safety:
This cop's autocorrection is unsafe since any strings mutations will
change from being accepted to raising FrozenError
, as all strings
will become frozen by default, and will need to be manually refactored.
Example: EnforcedStyle: always (default)
# The `always` style will always add the frozen string literal comment
# to a file, regardless of the Ruby version or if `freeze` or `<<` are
# called on a string literal.
# bad
module Bar
# ...
end
# good
# frozen_string_literal: true
module Bar
# ...
end
# good
# frozen_string_literal: false
module Bar
# ...
end
Example: EnforcedStyle: never
# The `never` will enforce that the frozen string literal comment does
# not exist in a file.
# bad
# frozen_string_literal: true
module Baz
# ...
end
# good
module Baz
# ...
end
Example: EnforcedStyle: always_true
# The `always_true` style enforces that the frozen string literal
# comment is set to `true`. This is a stricter option than `always`
# and forces projects to use frozen string literals.
# bad
# frozen_string_literal: false
module Baz
# ...
end
# bad
module Baz
# ...
end
# good
# frozen_string_literal: true
module Bar
# ...
end