class RuboCop::Cop::Performance::UnfreezeString
In Ruby 2.3 or later, use unary plus operator to unfreeze a string literal instead of `String#dup` and `String.new`. Unary plus operator is faster than `String#dup`.
Note: `String.new` (without operator) is not exactly the same as `+''`. These differ in encoding. `String.new.encoding` is always `ASCII-8BIT`. However, `(+'').encoding` is the same as script encoding(e.g. `UTF-8`). So, if you expect `ASCII-8BIT` encoding, disable this cop.
@example
# bad ''.dup "something".dup String.new String.new('') String.new('something') # good +'something' +''
Constants
- MSG
Public Instance Methods
on_send(node)
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# File lib/rubocop/cop/performance/unfreeze_string.rb, line 44 def on_send(node) add_offense(node) if dup_string?(node) || string_new?(node) end