Enabled frozen string literals (#1154)

* Enabled frozen string literals

* Update rubocop config

* Prefer string interpolation in simple cases

Co-Authored-By: Dylan Thacker-Smith <dylan.smith@shopify.com>

performance/benchmark.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'benchmark/ips'
 require_relative 'theme_runner'
 

performance/profile.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stackprof'
 require_relative 'theme_runner'
 

performance/shopify/comment_form.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class CommentForm < Liquid::Block
   Syntax = /(#{Liquid::VariableSignature}+)/
 

performance/shopify/database.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'yaml'
 
 module Database

performance/shopify/json_filter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'json'
 
 module JsonFilter

performance/shopify/liquid.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 $LOAD_PATH.unshift(__dir__ + '/../../lib')
 require_relative '../../lib/liquid'
 

performance/shopify/money_filter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module MoneyFilter
   def money_with_currency(money)
     return '' if money.nil?

performance/shopify/paginate.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class Paginate < Liquid::Block
   Syntax = /(#{Liquid::QuotedFragment})\s*(by\s*(\d+))?/
 

performance/shopify/shop_filter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ShopFilter
   def asset_url(input)
     "/files/1/[shop_id]/[shop_id]/assets/#{input}"

performance/shopify/tag_filter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module TagFilter
   def link_to_tag(label, tag)
     "<a title=\"Show tag #{tag}\" href=\"/collections/#{@context['handle']}/#{tag}\">#{label}</a>"

performance/shopify/weight_filter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module WeightFilter
   def weight(grams)
     format("%.2f", grams / 1000)

performance/theme_runner.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # This profiler run simulates Shopify.
 # We are looking in the tests directory for liquid files and render them within the designated layout file.
 # We will also export a substantial database to liquid which the templates can render values of.