Showing 136 of 136 total issues
Use 2 spaces for indentation in a heredoc by using <<~
instead of <<-
. Open
A pattern based Dalvik deobfuscator which uses limited execution to improve semantic analysis.
EOF
- Read upRead up
- Exclude checks
This cops checks the indentation of the here document bodies. The bodies
are indented one step.
In Ruby 2.3 or newer, squiggly heredocs (<<~
) should be used. If you
use the older rubies, you should introduce some library to your project
(e.g. ActiveSupport, Powerpack or Unindent).
Note: When Metrics/LineLength
's AllowHeredoc
is false(not default),
this cop does not add any offenses for long here documents to
avoid Metrics/LineLength
's offenses.
Example:
# bad
<<-RUBY
something
RUBY
# good
# When EnforcedStyle is squiggly, bad code is auto-corrected to the
# following code.
<<~RUBY
something
RUBY
# good
# When EnforcedStyle is active_support, bad code is auto-corrected to
# the following code.
<<-RUBY.strip_heredoc
something
RUBY
Missing magic comment # frozen_string_literal: true
. Open
# -*- encoding: utf-8 -*-
- Read upRead up
- Exclude checks
This cop is designed to help upgrade to Ruby 3.0. It will add the
comment # frozen_string_literal: true
to the top of files to
enable frozen string literals. Frozen string literals may be default
in Ruby 3.0. The comment will be added below a shebang and encoding
comment. The frozen string literal comment is only valid in Ruby 2.3+.
Example: EnforcedStyle: when_needed (default)
# The `when_needed` style will add the frozen string literal comment
# to files only when the `TargetRubyVersion` is set to 2.3+.
# bad
module Foo
# ...
end
# good
# frozen_string_literal: true
module Foo
# ...
end
Example: EnforcedStyle: always
# 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
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
%w
-literals should be delimited by [
and ]
. Open
exclude_files = Dir['driver/{build,bin}/**/*'] + Dir['sandbox/**/*'] + Dir['coverage/**/*'] + Dir['docker/**/*'] + %w(driver/build driver/bin sandbox coverage docker .dockerignore)
- Read upRead up
- Exclude checks
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)
Unnecessary utf-8 encoding comment. Open
# encoding: utf-8
- Exclude checks
Use match?
instead of =~
when MatchData
is not used. Open
if str =~ /\A\[(?:\d+(?:,\d+)*)?\]\z/
- Read upRead up
- Exclude checks
In Ruby 2.4, String#match?
, Regexp#match?
and Symbol#match?
have been added. The methods are faster than match
.
Because the methods avoid creating a MatchData
object or saving
backref.
So, when MatchData
is not used, use match?
instead of match
.
Example:
# bad
def foo
if x =~ /re/
do_something
end
end
# bad
def foo
if x.match(/re/)
do_something
end
end
# bad
def foo
if /re/ === x
do_something
end
end
# good
def foo
if x.match?(/re/)
do_something
end
end
# good
def foo
if x =~ /re/
do_something(Regexp.last_match)
end
end
# good
def foo
if x.match(/re/)
do_something($~)
end
end
# good
def foo
if /re/ === x
do_something($~)
end
end
The use of eval
is a serious security risk. Open
str = eval(str)
- Read upRead up
- Exclude checks
This cop checks for the use of Kernel#eval
and Binding#eval
.
Example:
# bad
eval(something)
binding.eval(something)
Avoid rescuing without specifying an error class. Open
rescue => e
- Read upRead up
- Exclude checks
This cop checks for rescuing StandardError
. There are two supported
styles implicit
and explicit
. This cop will not register an offense
if any error other than StandardError
is specified.
Example: EnforcedStyle: implicit
# `implicit` will enforce using `rescue` instead of
# `rescue StandardError`.
# bad
begin
foo
rescue StandardError
bar
end
# good
begin
foo
rescue
bar
end
# good
begin
foo
rescue OtherError
bar
end
# good
begin
foo
rescue StandardError, SecurityError
bar
end
Example: EnforcedStyle: explicit (default)
# `explicit` will enforce using `rescue StandardError`
# instead of `rescue`.
# bad
begin
foo
rescue
bar
end
# good
begin
foo
rescue StandardError
bar
end
# good
begin
foo
rescue OtherError
bar
end
# good
begin
foo
rescue StandardError, SecurityError
bar
end
Prefer single-quoted strings when you don't need string interpolation or special symbols. Open
next if stdout == "opendir failed, Permission denied"
- Read upRead up
- Exclude checks
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"
Use attr_reader
to define trivial reader methods. Open
def self.plugins
- Read upRead up
- Exclude checks
This cop looks for trivial reader/writer methods, that could have been created with the attr_* family of functions automatically.
Example:
# bad
def foo
@foo
end
def bar=(val)
@bar = val
end
def self.baz
@baz
end
# good
attr_reader :foo
attr_writer :bar
class << self
attr_reader :baz
end
Ambiguous negative number operator. Parenthesize the method arguments if it's surely a negative number operator, or add a whitespace to the right of the -
if it should be a subtraction. Open
exit -1
- Read upRead up
- Exclude checks
This cop checks for ambiguous operators in the first argument of a method invocation without parentheses.
Example:
# bad
# The `*` is interpreted as a splat operator but it could possibly be
# a `*` method invocation (i.e. `do_something.*(some_array)`).
do_something *some_array
Example:
# good
# With parentheses, there's no ambiguity.
do_something(*some_array)
Missing magic comment # frozen_string_literal: true
. Open
source 'https://rubygems.org'
- Read upRead up
- Exclude checks
This cop is designed to help upgrade to Ruby 3.0. It will add the
comment # frozen_string_literal: true
to the top of files to
enable frozen string literals. Frozen string literals may be default
in Ruby 3.0. The comment will be added below a shebang and encoding
comment. The frozen string literal comment is only valid in Ruby 2.3+.
Example: EnforcedStyle: when_needed (default)
# The `when_needed` style will add the frozen string literal comment
# to files only when the `TargetRubyVersion` is set to 2.3+.
# bad
module Foo
# ...
end
# good
# frozen_string_literal: true
module Foo
# ...
end
Example: EnforcedStyle: always
# 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
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
Do not use spaces between ->
and opening brace in lambda literals Open
MODIFIER = -> (_, output, out_reg) { "const-string #{out_reg}, \"#{output.split('').collect { |e| e.inspect[1..-2] }.join}\"" }
- Read upRead up
- Exclude checks
This cop checks for spaces between -> and opening parameter brace in lambda literals.
Example: EnforcedStyle: requirenospace (default)
# bad
a = -> (x, y) { x + y }
# good
a = ->(x, y) { x + y }
Example: EnforcedStyle: require_space
# bad
a = ->(x, y) { x + y }
# good
a = -> (x, y) { x + y }
Unused block argument - out_reg
. If it's necessary, use _
or _out_reg
as an argument name to indicate that it won't be used. Open
FILTER = -> (_, output, out_reg) { output == 'null' }
- Read upRead up
- Exclude checks
This cop checks for unused block arguments.
Example:
# bad
do_something do |used, unused|
puts used
end
do_something do |bar|
puts :foo
end
define_method(:foo) do |bar|
puts :baz
end
Example:
#good
do_something do |used, _unused|
puts used
end
do_something do
puts :foo
end
define_method(:foo) do |_bar|
puts :baz
end
Missing magic comment # frozen_string_literal: true
. Open
require 'logger'
- Read upRead up
- Exclude checks
This cop is designed to help upgrade to Ruby 3.0. It will add the
comment # frozen_string_literal: true
to the top of files to
enable frozen string literals. Frozen string literals may be default
in Ruby 3.0. The comment will be added below a shebang and encoding
comment. The frozen string literal comment is only valid in Ruby 2.3+.
Example: EnforcedStyle: when_needed (default)
# The `when_needed` style will add the frozen string literal comment
# to files only when the `TargetRubyVersion` is set to 2.3+.
# bad
module Foo
# ...
end
# good
# frozen_string_literal: true
module Foo
# ...
end
Example: EnforcedStyle: always
# 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
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
Convert if
nested inside else
to elsif
. Open
full_path if entry.downcase.end_with?(ext)
- Read upRead up
- Exclude checks
If the else
branch of a conditional consists solely of an if
node,
it can be combined with the else
to become an elsif
.
This helps to keep the nesting level from getting too deep.
Example:
# bad
if condition_a
action_a
else
if condition_b
action_b
else
action_c
end
end
# good
if condition_a
action_a
elsif condition_b
action_b
else
action_c
end
Space found before semicolon. Open
optimizations = optimizations.inject(Hash.new(0)) { |memo, subhash| subhash.each { |prod, value| memo[prod] += value } ; memo }
- Read upRead up
- Exclude checks
Checks for semicolon (;) preceded by space.
Example:
# bad
x = 1 ; y = 2
# good
x = 1; y = 2
Useless assignment to variable - smali_files
. Open
smali_files = file_paths.collect { |path| SmaliFile.new(path) }
- Read upRead up
- Exclude checks
This cop checks for every useless assignment to local variable in every
scope.
The basic idea for this cop was from the warning of ruby -cw
:
assigned but unused variable - foo
Currently this cop has advanced logic that detects unreferenced reassignments and properly handles varied cases such as branch, loop, rescue, ensure, etc.
Example:
# bad
def some_method
some_var = 1
do_something
end
Example:
# good
def some_method
some_var = 1
do_something(some_var)
end
Useless private
access modifier. Open
private
- Read upRead up
- Exclude checks
This cop checks for redundant access modifiers, including those with no
code, those which are repeated, and leading public
modifiers in a
class or module body. Conditionally-defined methods are considered as
always being defined, and thus access modifiers guarding such methods
are not redundant.
Example:
class Foo
public # this is redundant (default access is public)
def method
end
private # this is not redundant (a method is defined)
def method2
end
private # this is redundant (no following methods are defined)
end
Example:
class Foo
# The following is not redundant (conditionally defined methods are
# considered as always defining a method)
private
if condition?
def method
end
end
protected # this is not redundant (method is defined)
define_method(:method2) do
end
protected # this is redundant (repeated from previous modifier)
[1,2,3].each do |i|
define_method("foo#{i}") do
end
end
# The following is redundant (methods defined on the class'
# singleton class are not affected by the public modifier)
public
def self.method3
end
end
Example:
# Lint/UselessAccessModifier:
# ContextCreatingMethods:
# - concerning
require 'active_support/concern'
class Foo
concerning :Bar do
def some_public_method
end
private
def some_private_method
end
end
# this is not redundant because `concerning` created its own context
private
def some_other_private_method
end
end
Example:
# Lint/UselessAccessModifier:
# MethodCreatingMethods:
# - delegate
require 'active_support/core_ext/module/delegation'
class Foo
# this is not redundant because `delegate` creates methods
private
delegate :method_a, to: :method_b
end
Avoid using {...}
for multi-line blocks. Open
Open3.popen3(cmd) { |_, stdout, stderr, _|
- Read upRead up
- Exclude checks
Check for uses of braces or do/end around single line or multi-line blocks.
Example: EnforcedStyle: linecountbased (default)
# bad - single line block
items.each do |item| item / 5 end
# good - single line block
items.each { |item| item / 5 }
# bad - multi-line block
things.map { |thing|
something = thing.some_method
process(something)
}
# good - multi-line block
things.map do |thing|
something = thing.some_method
process(something)
end
Example: EnforcedStyle: semantic
# Prefer `do...end` over `{...}` for procedural blocks.
# return value is used/assigned
# bad
foo = map do |x|
x
end
puts (map do |x|
x
end)
# return value is not used out of scope
# good
map do |x|
x
end
# Prefer `{...}` over `do...end` for functional blocks.
# return value is not used out of scope
# bad
each { |x|
x
}
# return value is used/assigned
# good
foo = map { |x|
x
}
map { |x|
x
}.inspect
Example: EnforcedStyle: bracesforchaining
# bad
words.each do |word|
word.flip.flop
end.join("-")
# good
words.each { |word|
word.flip.flop
}.join("-")
Add an empty line after magic comments. Open
$LOAD_PATH.push('lib')
- Read upRead up
- Exclude checks
Checks for a newline after the final magic comment.
Example:
# good
# frozen_string_literal: true
# Some documentation for Person
class Person
# Some code
end
# bad
# frozen_string_literal: true
# Some documentation for Person
class Person
# Some code
end