Refactoring by template

code/array/shuffle-first-vs-sample.rb

@@ -2,16 +2,16 @@
 
 ARRAY = [*1..100]
 
-def slow
-  ARRAY.shuffle.first
-end
-
 def fast
   ARRAY.sample
 end
 
+def slow
+  ARRAY.shuffle.first
+end
+
 Benchmark.ips do |x|
-  x.report('Array#shuffle.first') { slow }
   x.report('Array#sample')        { fast }
+  x.report('Array#shuffle.first') { slow }
   x.compare!
 end

code/enumerable/each-push-vs-map.rb

@@ -2,17 +2,17 @@
 
 ARRAY = (1..100).to_a
 
+def fast
+  ARRAY.map { |i| i }
+end
+
 def slow
   array = []
   ARRAY.each { |i| array.push i }
 end
 
-def fast
-  ARRAY.map { |i| i }
-end
-
 Benchmark.ips do |x|
-  x.report('Array#each + push') { slow }
   x.report('Array#map')         { fast }
+  x.report('Array#each + push') { slow }
   x.compare!
 end

code/enumerable/each-vs-for-loop.rb

@@ -2,20 +2,20 @@
 
 ARRAY = [*1..100]
 
-def slow
-  for number in ARRAY do
+def fast
+  ARRAY.each do |number|
     number
   end
 end
 
-def fast
-  ARRAY.each do |number|
+def slow
+  for number in ARRAY do
     number
   end
 end
 
 Benchmark.ips do |x|
-  x.report('For loop') { slow  }
   x.report('#each')    { fast  }
+  x.report('For loop') { slow  }
   x.compare!
 end

code/enumerable/map-flatten-vs-flat_map.rb

@@ -2,6 +2,10 @@
 
 ARRAY = (1..100).to_a
 
+def fast
+  ARRAY.flat_map { |e| [e, e] }
+end
+
 def slow_flatten_1
   ARRAY.map { |e| [e, e] }.flatten(1)
 end
@@ -10,13 +14,9 @@ def slow_flatten
   ARRAY.map { |e| [e, e] }.flatten
 end
 
-def fast
-  ARRAY.flat_map { |e| [e, e] }
-end
-
 Benchmark.ips do |x|
+  x.report('Array#flat_map')       { fast           }
   x.report('Array#map.flatten(1)') { slow_flatten_1 }
   x.report('Array#map.flatten')    { slow_flatten   }
-  x.report('Array#flat_map')       { fast           }
   x.compare!
 end

code/enumerable/reverse-each-vs-reverse_each.rb

@@ -2,16 +2,16 @@
 
 ARRAY = (1..100).to_a
 
-def slow
-  ARRAY.reverse.each{|x| x}
-end
-
 def fast
   ARRAY.reverse_each{|x| x}
 end
 
+def slow
+  ARRAY.reverse.each{|x| x}
+end
+
 Benchmark.ips do |x|
-  x.report('Array#reverse.each') { slow }
   x.report('Array#reverse_each') { fast }
+  x.report('Array#reverse.each') { slow }
   x.compare!
 end

code/enumerable/select-first-vs-detect.rb

@@ -2,16 +2,16 @@
 
 ARRAY = [*1..100]
 
-def slow
-  ARRAY.select { |x| x.eql?(15) }.first
-end
-
 def fast
   ARRAY.detect { |x| x.eql?(15) }
 end
 
+def slow
+  ARRAY.select { |x| x.eql?(15) }.first
+end
+
 Benchmark.ips(20) do |x|
-  x.report('Enumerable#select.first') { slow }
   x.report('Enumerable#detect') { fast }
+  x.report('Enumerable#select.first') { slow }
   x.compare!
 end

code/general/attr-accessor-vs-getter-and-setter.rb

@@ -13,20 +13,20 @@ def last_name=(value)
 
 end
 
-def slow
-  user = User.new
-  user.last_name = 'John'
-  user.last_name
-end
-
 def fast
   user = User.new
   user.first_name = 'John'
   user.first_name
 end
 
+def slow
+  user = User.new
+  user.last_name = 'John'
+  user.last_name
+end
+
 Benchmark.ips do |x|
-  x.report('getter_and_setter') { slow }
   x.report('attr_accessor')     { fast }
+  x.report('getter_and_setter') { slow }
   x.compare!
 end

code/general/begin-rescue-vs-respond-to.rb

@@ -1,23 +1,23 @@
 require 'benchmark/ips'
 
-def slow
-  begin
+def fast
+  if respond_to?(:writing)
     writing
-  rescue
+  else
     'fast ruby'
   end
 end
 
-def fast
-  if respond_to?(:writing)
+def slow
+  begin
     writing
-  else
+  rescue
     'fast ruby'
   end
 end
 
 Benchmark.ips do |x|
-  x.report('begin...rescue') { slow }
   x.report('respond_to?')    { fast }
+  x.report('begin...rescue') { slow }
   x.compare!
 end

code/hash/keys-each-vs-each_key.rb

@@ -38,17 +38,16 @@
   }
 }
 
+def fast
+  HASH.each_key(&:to_sym)
+end
 
 def slow
   HASH.keys.each(&:to_sym)
 end
 
-def fast
-  HASH.each_key(&:to_sym)
-end
-
 Benchmark.ips do |x|
-  x.report('Hash#keys.each') { slow }
   x.report('Hash#each_key')  { fast }
+  x.report('Hash#keys.each') { slow }
   x.compare!
 end

code/hash/merge-bang-vs-[]=.rb

@@ -2,20 +2,20 @@
 
 ENUM = (1..100)
 
-def slow
+def fast
   ENUM.each_with_object({}) do |e, h|
-    h.merge!(e => e)
+    h[e] = e
   end
 end
 
-def fast
+def slow
   ENUM.each_with_object({}) do |e, h|
-    h[e] = e
+    h.merge!(e => e)
   end
 end
 
 Benchmark.ips do |x|
-  x.report('Hash#merge!') { slow }
   x.report('Hash#[]=') { fast }
+  x.report('Hash#merge!') { slow }
   x.compare!
 end

code/hash/merge-vs-merge-bang.rb

@@ -2,20 +2,20 @@
 
 ENUM = (1..100)
 
-def slow
+def fast
   ENUM.inject({}) do |h, e|
-    h.merge(e => e)
+    h.merge!(e => e)
   end
 end
 
-def fast
+def slow
   ENUM.inject({}) do |h, e|
-    h.merge!(e => e)
+    h.merge(e => e)
   end
 end
 
 Benchmark.ips do |x|
-  x.report('Hash#merge') { slow }
   x.report('Hash#merge!') { fast }
+  x.report('Hash#merge') { slow }
   x.compare!
 end

code/proc-and-block/block-vs-to_proc.rb

@@ -2,16 +2,16 @@
 
 RANGE = (1..100)
 
-def slow
-  RANGE.map { |i| i.to_s }
-end
-
 def fast
   RANGE.map(&:to_s)
 end
 
+def slow
+  RANGE.map { |i| i.to_s }
+end
+
 Benchmark.ips do |x|
-  x.report('Block')          { slow }
   x.report('Symbol#to_proc') { fast }
+  x.report('Block')          { slow }
   x.compare!
 end

code/proc-and-block/proc-call-vs-yield.rb

@@ -1,5 +1,9 @@
 require 'benchmark/ips'
 
+def fast
+  yield
+end
+
 def slow(&block)
   block.call
 end
@@ -12,14 +16,10 @@ def slow3(&block)
 
 end
 
-def fast
-  yield
-end
-
 Benchmark.ips do |x|
+  x.report('yield')      { fast { 1 + 1 } }
   x.report('block.call') { slow { 1 + 1 } }
   x.report('block + yield') { slow2 { 1 + 1 } }
   x.report('unused block') { slow3 { 1 + 1 } }
-  x.report('yield')      { fast { 1 + 1 } }
   x.compare!
 end

code/string/casecmp-vs-downcase-==.rb

@@ -2,16 +2,16 @@
 
 SLUG = 'ABCD'
 
-def slow
-  SLUG.downcase == 'abcd'
-end
-
 def fast
   SLUG.casecmp('abcd') == 0
 end
 
+def slow
+  SLUG.downcase == 'abcd'
+end
+
 Benchmark.ips do |x|
-  x.report('String#downcase + ==') { slow }
   x.report('String#casecmp')       { fast }
+  x.report('String#downcase + ==') { slow }
   x.compare!
 end

code/string/concatenation.rb

@@ -1,5 +1,14 @@
 require 'benchmark/ips'
 
+# 1 object
+def fast
+  'foo' 'bar'
+end
+
+def fast_interpolation
+  "#{'foo'}#{'bar'}"
+end
+
 # 2 + 1 = 3 object
 def slow_plus
   'foo' + 'bar'
@@ -15,20 +24,11 @@ def slow_append
   'foo' << 'bar'
 end
 
-# 1 object
-def fast
-  'foo' 'bar'
-end
-
-def fast_interpolation
-  "#{'foo'}#{'bar'}"
-end
-
 Benchmark.ips do |x|
+  x.report('"#{\'foo\'}#{\'bar\'}"')   { fast_interpolation }
+  x.report('"foo" "bar"')              { fast }
   x.report('String#+')                 { slow_plus }
   x.report('String#concat')            { slow_concat }
   x.report('String#append')            { slow_append }
-  x.report('"foo" "bar"')              { fast }
-  x.report('"#{\'foo\'}#{\'bar\'}"')   { fast_interpolation }
   x.compare!
 end