cloudamatic/mu

This cop checks if the length of a block exceeds some maximum value. Comment lines can optionally be ignored. The maximum allowed length is configurable. The cop can be configured to ignore blocks passed to certain methods.

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 checks for uses of the deprecated class method usages.

Example:

# bad

File.exists?(some_path)

Example:

# good

File.exist?(some_path)

This cop checks for string conversion in string interpolation, which is redundant.

Example:

# bad

"result is #{something.to_s}"

Example:

# good

"result is #{something}"

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 whether the end keywords are aligned properly.

Three modes are supported through the EnforcedStyleAlignWith configuration parameter:

If it's set to keyword (which is the default), the end shall be aligned with the start of the keyword (if, class, etc.).

If it's set to variable the end shall be aligned with the left-hand-side of the variable assignment, if there is one.

If it's set to start_of_line, the end shall be aligned with the start of the line where the matching keyword appears.

Example: EnforcedStyleAlignWith: keyword (default)

# bad

variable = if true
    end

# good

variable = if true
           end

Example: EnforcedStyleAlignWith: variable

# bad

variable = if true
    end

# good

variable = if true
end

Example: EnforcedStyleAlignWith: startofline

# bad

variable = if true
    end

# good

puts(if true
end)

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 for uses of the deprecated class method usages.

Example:

# bad

File.exists?(some_path)

Example:

# good

File.exist?(some_path)

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 whether the end keywords are aligned properly.

Three modes are supported through the EnforcedStyleAlignWith configuration parameter:

If it's set to keyword (which is the default), the end shall be aligned with the start of the keyword (if, class, etc.).

If it's set to variable the end shall be aligned with the left-hand-side of the variable assignment, if there is one.

If it's set to start_of_line, the end shall be aligned with the start of the line where the matching keyword appears.

Example: EnforcedStyleAlignWith: keyword (default)

# bad

variable = if true
    end

# good

variable = if true
           end

Example: EnforcedStyleAlignWith: variable

# bad

variable = if true
    end

# good

variable = if true
end

Example: EnforcedStyleAlignWith: startofline

# bad

variable = if true
    end

# good

puts(if true
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