require 'benchmark/ips'

Benchmark.ips do |x|
  path_without_ending_slash = '/some/very/very/long/path/to/a/file/i/like'
  x.report('no slash regexp')    { path_without_ending_slash =~ /\/$/ }
  x.report('no slash end_with?') { path_without_ending_slash.end_with?("/")  }
end

Benchmark.ips do |x|
  path_with_ending_slash = '/some/very/very/long/path/to/a/file/i/like/'
  x.report('slash regexp')    { path_with_ending_slash =~ /\/$/ }
  x.report('slash end_with?') { path_with_ending_slash.end_with?("/")  }
end