Showing 2,704 of 2,705 total issues
Use meaningful heredoc delimiters. Open
EOS
- Read upRead up
- Exclude checks
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
Unused block argument - cfg
. If it's necessary, use _
or _cfg
as an argument name to indicate that it won't be used. Open
MU::Cloud.resource_types.each_pair { |type, cfg|
- 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
Unused block argument - subkey
. If it's necessary, use _
or _subkey
as an argument name to indicate that it won't be used. Open
data["subtree"].each_pair { |subkey, subdata|
- 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
Avoid more than 4 levels of block nesting. Open
newtree['default']['value'] = true if newtree['default']
- Read upRead up
- Exclude checks
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.
Avoid more than 4 levels of block nesting. Open
next if subkey.match(/^#/) or !subdata.is_a?(Hash)
- Read upRead up
- Exclude checks
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.
Useless assignment to variable - nat_ssh_user
. Open
nat_ssh_user = $opts[:user]
- 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
Unused block argument - n
. You can omit the argument if you don't care about it. Open
(0..100000).to_a.each { |n|
- 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
Use meaningful heredoc delimiters. Open
EOS
- Read upRead up
- Exclude checks
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
Do not suppress exceptions. Open
rescue OpenURI::HTTPError, Timeout::Error, SocketError, Errno::ENETUNREACH
- Read upRead up
- Exclude checks
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
Do not suppress exceptions. Open
rescue OpenURI::HTTPError, Timeout::Error, SocketError
- Read upRead up
- Exclude checks
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
Unused block argument - subkey
. If it's necessary, use _
or _subkey
as an argument name to indicate that it won't be used. Open
data["subtree"].each_pair { |subkey, subdata|
- 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
Useless assignment to variable - username
. Open
username = Etc.getpwuid(Process.uid).name
- 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
Use each_key
instead of keys.each
. Open
$CONFIGURABLES[key]["subtree"].keys.each { |subkey|
- Read upRead up
- Exclude checks
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 }
Do not suppress exceptions. Open
rescue Exception
- Read upRead up
- Exclude checks
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
Use each_key
instead of keys.each
. Open
signals.keys.each { |sig|
- Read upRead up
- Exclude checks
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 }
Use =~
in places where the MatchData
returned by #match
will not be used. Open
if e.message.match(/notFound:/)
- Read upRead up
- Exclude checks
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'
Use =~
in places where the MatchData
returned by #match
will not be used. Open
if e.message.match(/notFound:/)
- Read upRead up
- Exclude checks
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'
Redundant use of Object#to_s
in interpolation. Open
Syslog.log(Syslog::LOG_NOTICE, "Tunnel failure for #{dest_host}:#{dest_port} from config #{NAGIOS_HOME}/.ssh/config, `#{full_cmd}`: #{e.inspect} **** #{output} **** ENV: #{envhash.to_s}")
- Read upRead up
- Exclude checks
This cop checks for string conversion in string interpolation, which is redundant.
Example:
# bad
"result is #{something.to_s}"
Example:
# good
"result is #{something}"
Use tr
instead of gsub
. Open
t_name = t.gsub(/-/, "_")
- Read upRead up
- Exclude checks
This cop identifies places where gsub
can be replaced by
tr
or delete
.
Example:
# bad
'abc'.gsub('b', 'd')
'abc'.gsub('a', '')
'abc'.gsub(/a/, 'd')
'abc'.gsub!('a', 'd')
# good
'abc'.gsub(/.*/, 'a')
'abc'.gsub(/a+/, 'd')
'abc'.tr('b', 'd')
'a b c'.delete(' ')
Useless assignment to variable - ebs_key
. Open
ebs_key = nil
- 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