Optimize array! DSL (Round 2)

benchmarks/jbuilder_template/array_dsl.rb

@@ -7,14 +7,13 @@
 
 Post = Struct.new(:id, :body)
 json = JbuilderTemplate.new nil
-posts = 3.times.map { Post.new(it, "Post ##{it}") }
 
 Benchmark.ips do |x|
-  x.report('before') do
-    json.array!(nil)
+  x.report('before') do |n|
+    n.times { json.array! }
   end
-  x.report('after') do
-    json.array!(nil)
+  x.report('after') do |n|
+    n.times { json.array! }
   end
 
   x.hold! 'temp_array_ips'
@@ -24,8 +23,8 @@
 json = JbuilderTemplate.new nil
 
 Benchmark.memory do |x|
-  x.report('before') { json.array! posts, :id, :body }
-  x.report('after') { json.array! posts, :id, :body }
+  x.report('before') { json.array! }
+  x.report('after') { json.array! }
 
   x.hold! 'temp_array_memory'
   x.compare!

benchmarks/jbuilder_template/array_dsl_block.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require 'benchmark/ips'
+require 'benchmark/memory'
+require_relative '../../lib/jbuilder'
+require_relative '../../lib/jbuilder/jbuilder_template'
+
+Post = Struct.new(:id, :body)
+json = JbuilderTemplate.new nil
+array = [1, 2, 3]
+
+Benchmark.ips do |x|
+  x.report('before') do |n|
+    n.times do
+      json.array! array do |item|
+      end
+    end
+  end
+  x.report('after') do |n|
+    n.times do
+      json.array! array do |item|
+      end
+    end
+  end
+
+  x.hold! 'temp_array_ips'
+  x.compare!
+end
+
+json = JbuilderTemplate.new nil
+
+Benchmark.memory do |x|
+  x.report('before') do
+    json.array! array do |item|
+    end
+  end
+  x.report('after') do
+    json.array! array do |item|
+    end
+  end
+
+  x.hold! 'temp_array_memory'
+  x.compare!
+end

benchmarks/partials/array_dsl.rb

@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+require 'benchmark/ips'
+require 'benchmark/memory'
+require_relative 'setup'
+
+POST_PARTIAL = <<-JBUILDER
+  json.extract! post, :id, :body
+JBUILDER
+
+PARTIALS = { "_post.json.jbuilder" => POST_PARTIAL }
+
+Post = Struct.new(:id, :body)
+
+view = build_view(fixtures: PARTIALS)
+json = JbuilderTemplate.new view
+posts = 3.times.map { Post.new(it, "Post ##{it}") }
+
+Benchmark.ips do |x|
+  x.report('before') do |n|
+    n.times { json.array! posts, partial: "post", as: :post }
+  end
+
+  x.report('after') do |n|
+    n.times { json.array! posts, partial: "post", as: :post }
+  end
+
+  x.hold! 'temp_array_results_ips'
+  x.compare!
+end
+
+json = JbuilderTemplate.new view
+
+Benchmark.memory do |x|
+  x.report('before') do
+    json.array! posts, partial: "post", as: :post
+  end
+
+  x.report('after') do
+    json.array! posts, partial: "post", as: :post
+  end
+
+  x.hold! 'temp_array_results_memory'
+  x.compare!
+end

lib/jbuilder/jbuilder_template.rb

@@ -118,14 +118,16 @@ def target!
     @cached_root || super
   end
 
-  def array!(collection = EMPTY_ARRAY, *args, &block)
+  def array!(collection = EMPTY_ARRAY, *args)
     options = args.first
 
     if _partial_options?(options)
       options[:collection] = collection
       _render_partial_with_options options
+    elsif ::Kernel.block_given?
+      _array(collection, args) { |x| yield x }
     else
-      _array collection, args, &block
+      _array collection, args
     end
   end