cloudamatic/mu

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 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 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