cloudamatic/mu

This cop checks for excessive nesting of conditional and looping constructs.

You can configure if blocks are considered using the CountBlocks option. When set to false (the default) blocks are not counted towards the nesting level. Set to true to count blocks as well.

The maximum level of nesting allowed is configurable.

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

This cop checks for excessive nesting of conditional and looping constructs.

You can configure if blocks are considered using the CountBlocks option. When set to false (the default) blocks are not counted towards the nesting level. Set to true to count blocks as well.

The maximum level of nesting allowed is configurable.

This cop checks for uses of each_key and each_value Hash methods.

Note: If you have an array of two-element arrays, you can put parentheses around the block arguments to indicate that you're not working with a hash, and suppress RuboCop offenses.

Example:

# bad
hash.keys.each { |k| p k }
hash.values.each { |v| p v }
hash.each { |k, _v| p k }
hash.each { |_k, v| p v }
 
# good
hash.each_key { |k| p k }
hash.each_value { |v| p v }

This cop checks for the use of YAML class methods which have potential security issues leading to remote code execution when loading from an untrusted source.

Example:

# bad
YAML.load("--- foo")
 
# good
YAML.safe_load("--- foo")
YAML.dump("foo")

This cop checks for rescue blocks with no body.

Example:

# bad
 
def some_method
  do_something
rescue
  # do nothing
end

Example:

# bad
 
begin
  do_something
rescue
  # do nothing
end

Example:

# good
 
def some_method
  do_something
rescue
  handle_exception
end

Example:

# good
 
begin
  do_something
rescue
  handle_exception
end

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

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

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

This cop checks for excessive nesting of conditional and looping constructs.

You can configure if blocks are considered using the CountBlocks option. When set to false (the default) blocks are not counted towards the nesting level. Set to true to count blocks as well.

The maximum level of nesting allowed is configurable.

This cop checks for excessive nesting of conditional and looping constructs.

You can configure if blocks are considered using the CountBlocks option. When set to false (the default) blocks are not counted towards the nesting level. Set to true to count blocks as well.

The maximum level of nesting allowed is configurable.

This cop identifies the use of Regexp#match or String#match, which returns #<MatchData>/nil. The return value of =~ is an integral index/nil and is more performant.

Example:

# bad
do_something if str.match(/regex/)
while regex.match('str')
  do_something
end
 
# good
method(str =~ /regex/)
return value unless regex =~ 'str'

This cop identifies the use of Regexp#match or String#match, which returns #<MatchData>/nil. The return value of =~ is an integral index/nil and is more performant.

Example:

# bad
do_something if str.match(/regex/)
while regex.match('str')
  do_something
end
 
# good
method(str =~ /regex/)
return value unless regex =~ 'str'

This cop checks for uses of the deprecated class method usages.

Example:

# bad
 
File.exists?(some_path)

Example:

# good
 
File.exist?(some_path)

This cop checks that your heredocs are using meaningful delimiters. By default it disallows END and EO*, and can be configured through blacklisting additional delimiters.

Example:

# good
<<-SQL
  SELECT * FROM foo
SQL
 
# bad
<<-END
  SELECT * FROM foo
END
 
# bad
<<-EOS
  SELECT * FROM foo
EOS

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

This cop checks for rescue blocks with no body.

Example:

# bad
 
def some_method
  do_something
rescue
  # do nothing
end

Example:

# bad
 
begin
  do_something
rescue
  # do nothing
end

Example:

# good
 
def some_method
  do_something
rescue
  handle_exception
end

Example:

# good
 
begin
  do_something
rescue
  handle_exception
end

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

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

This cop checks for rescue blocks targeting the Exception class.

Example:

# bad
 
begin
  do_something
rescue Exception
  handle_exception
end

Example:

# good
 
begin
  do_something
rescue ArgumentError
  handle_exception
end