Add benchmarks for Page#dir

benchmark/end-with-vs-regexp

@@ -4,10 +4,12 @@ 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?("/")  }
+  x.report('no slash [-1, 1]') { path_without_ending_slash[-1, 1] == "/"  }
 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?("/")  }
+  x.report('slash [-1, 1]')   { path_with_ending_slash[-1, 1] == "/"  }
 end

benchmark/file-dir-ensure-trailing-slash

@@ -0,0 +1,54 @@
+#!/usr/bin/env ruby
+require 'benchmark/ips'
+
+# For this pull request, which changes Page#dir
+# https://github.com/jekyll/jekyll/pull/4403
+
+FORWARD_SLASH = '/'.freeze
+
+def pre_pr(url)
+  url[-1, 1] == FORWARD_SLASH ? url : File.dirname(url)
+end
+
+def pr(url)
+  if url.end_with?(FORWARD_SLASH)
+    url
+  else
+    url_dir = File.dirname(url)
+    url_dir.end_with?(FORWARD_SLASH) ? url_dir : "#{url_dir}/"
+  end
+end
+
+def envygeeks(url)
+  return url if url.end_with?(FORWARD_SLASH) || url == FORWARD_SLASH
+
+  url = File.dirname(url)
+  url == FORWARD_SLASH ? url : "#{url}/"
+end
+
+# Just a slash
+Benchmark.ips do |x|
+  path = '/'
+  x.report("pre_pr:#{path}")    { pre_pr(path) }
+  x.report("pr:#{path}")        { pr(path) }
+  x.report("envygeeks:#{path}") { pr(path) }
+  x.compare!
+end
+
+# No trailing slash
+Benchmark.ips do |x|
+  path = '/some/very/very/long/path/to/a/file/i/like'
+  x.report("pre_pr:#{path}")    { pre_pr(path) }
+  x.report("pr:#{path}")        { pr(path) }
+  x.report("envygeeks:#{path}") { pr(path) }
+  x.compare!
+end
+
+# No trailing slash
+Benchmark.ips do |x|
+  path = '/some/very/very/long/path/to/a/file/i/like/'
+  x.report("pre_pr:#{path}")    { pre_pr(path) }
+  x.report("pr:#{path}")        { pr(path) }
+  x.report("envygeeks:#{path}") { pr(path) }
+  x.compare!
+end