add frozen_string_literal magic comment (#1408)

for efficient string storage since we don't mutate any of the string
literals after they have been declared. in essence, they're already
being used as frozen values.

lib/jsonapi-resources.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'jsonapi/resources/railtie'
 require 'jsonapi/naive_cache'
 require 'jsonapi/compiled_json'

lib/jsonapi/active_relation_resource.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class ActiveRelationResource < BasicResource
     root_resource

lib/jsonapi/acts_as_resource_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'csv'
 
 module JSONAPI

lib/jsonapi/basic_resource.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'jsonapi/callbacks'
 require 'jsonapi/configuration'
 

lib/jsonapi/cached_response_fragment.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class CachedResponseFragment
 

lib/jsonapi/callbacks.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'active_support/callbacks'
 
 module JSONAPI

lib/jsonapi/compiled_json.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class CompiledJson
     def self.compile(h)

lib/jsonapi/configuration.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'jsonapi/formatter'
 require 'jsonapi/processor'
 require 'concurrent'

lib/jsonapi/error.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Error
     attr_accessor :title, :detail, :id, :href, :code, :source, :links, :status, :meta

lib/jsonapi/error_codes.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   VALIDATION_ERROR = '100'
   INVALID_RESOURCE = '101'

lib/jsonapi/exceptions.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   module Exceptions
     class Error < RuntimeError

lib/jsonapi/formatter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Formatter
     class << self

lib/jsonapi/include_directives.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class IncludeDirectives
     # Construct an IncludeDirectives Hash from an array of dot separated include strings.

lib/jsonapi/link_builder.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class LinkBuilder
     attr_reader :base_url,

lib/jsonapi/mime_types.rb

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

lib/jsonapi/naive_cache.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
 
   # Cache which memoizes the given block.

lib/jsonapi/operation.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Operation
     attr_reader :resource_klass, :operation_type, :options

lib/jsonapi/operation_result.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class OperationResult
     attr_accessor :code

lib/jsonapi/paginator.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Paginator
     def initialize(_params)

lib/jsonapi/path.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Path
     attr_reader :segments, :resource_klass

lib/jsonapi/path_segment.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class PathSegment
     def self.parse(source_resource_klass:, segment_string:, parse_fields: true)

lib/jsonapi/processor.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Processor
     include Callbacks

lib/jsonapi/relationship.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Relationship
     attr_reader :acts_as_set, :foreign_key, :options, :name,

lib/jsonapi/request.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Request
     attr_accessor :fields, :include, :filters, :sort_criteria, :errors, :controller_module_path,

lib/jsonapi/resource.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class Resource < ActiveRelationResource
     root_resource

lib/jsonapi/resource_controller.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class ResourceController < ActionController::Base
     include JSONAPI::ActsAsResourceController

lib/jsonapi/resource_controller_metal.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class ResourceControllerMetal < ActionController::Metal
     MODULES = [

lib/jsonapi/resource_fragment.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
 
   # A ResourceFragment holds a ResourceIdentity and associated partial resource data.

lib/jsonapi/resource_identity.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
 
   # ResourceIdentity describes a unique identity of a resource in the system.

lib/jsonapi/resource_serializer.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class ResourceSerializer
 

lib/jsonapi/resource_set.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   # Contains a hash of resource types which contain a hash of resources, relationships and primary status keyed by
   # resource id.

lib/jsonapi/resource_tree.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
 
   # A tree structure representing the resource structure of the requested resource(s). This is an intermediate structure

lib/jsonapi/response_document.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module JSONAPI
   class ResponseDocument
     attr_reader :serialized_results

lib/jsonapi/routing_ext.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActionDispatch
   module Routing
     class Mapper