Remove OpenStruct usage

Loading the gem on Ruby 3.3.5 or 3.4.0-preview1 prints this warning:

    lib/jira-ruby.rb:53: warning: ostruct was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.5.0.
    You can add ostruct to your Gemfile or gemspec to silence this warning.

OpenStruct is used to store two values, field_map and field_map_reverse,
but only field_map was used, so we can store it directly in an instance
variable and remove the dependency on OpenStruct.

.rubocop.yml

@@ -178,9 +178,6 @@ Style/ClassAndModuleChildren:
 Style/MissingRespondToMissing:
   Enabled: false
 
-Style/OpenStructUse:
-  Enabled: false
-
 Style/OptionalBooleanParameter:
   Enabled: false
 

lib/jira/client.rb

@@ -2,7 +2,6 @@
 
 require 'json'
 require 'forwardable'
-require 'ostruct'
 
 module JIRA
   # This class is the main access point for all JIRA::Resource instances.
@@ -55,7 +54,7 @@ class Client
     #
     # The authenticated client instance returned by the respective client type
     # (Oauth, Basic)
-    attr_accessor :consumer, :request_client, :http_debug, :cache
+    attr_accessor :consumer, :request_client, :http_debug, :field_map_cache
 
     # The configuration options for this client instance
     attr_reader :options
@@ -164,8 +163,6 @@ def initialize(options = {})
       @http_debug = @options[:http_debug]
 
       @options.freeze
-
-      @cache = OpenStruct.new
     end
 
     def Project # :nodoc:

lib/jira/resource/field.rb

@@ -21,7 +21,6 @@ def self.safer_name(description, jira_id)
 
       def self.map_fields(client)
         field_map = {}
-        field_map_reverse = {}
         fields = client.Field.all
 
         # two pass approach, so that a custom field with the same name
@@ -30,7 +29,6 @@ def self.map_fields(client)
           next if f.custom
 
           name = safe_name(f.name)
-          field_map_reverse[f.id] = [f.name, name] # capture both the official name, and the mapped name
           field_map[name] = f.id
         end
 
@@ -44,23 +42,21 @@ def self.map_fields(client)
                  else
                    safe_name(f.name)
                  end
-          field_map_reverse[f.id] = [f.name, name] # capture both the official name, and the mapped name
           field_map[name] = f.id
         end
 
-        client.cache.field_map_reverse = field_map_reverse # not sure where this will be used yet, but sure to be useful
-        client.cache.field_map = field_map
+        client.field_map_cache = field_map
       end
 
       def self.field_map(client)
-        client.cache.field_map
+        client.field_map_cache
       end
 
       def self.name_to_id(client, field_name)
         field_name = field_name.to_s
-        return field_name unless client.cache.field_map && client.cache.field_map[field_name]
+        return field_name unless client.field_map_cache && client.field_map_cache[field_name]
 
-        client.cache.field_map[field_name]
+        client.field_map_cache[field_name]
       end
 
       def respond_to?(method_name, _include_all = false)

spec/integration/user_spec.rb

@@ -41,7 +41,7 @@
 
       before do
         allow(client).to receive(:get)
-          .with('/rest/api/2/users/search?username=_&maxResults=1000') { OpenStruct.new(body: '["User1"]') }
+          .with('/rest/api/2/users/search?username=_&maxResults=1000') { double(body: '["User1"]') }
         allow(client).to receive_message_chain(:User, :build).with('users') { [] }
       end
 

spec/jira/resource/board_spec.rb

@@ -107,15 +107,15 @@ class JIRAResourceDelegation < SimpleDelegator # :nodoc:
 
       context 'when there are multiple pages of results' do
         let(:result_1) do
-          OpenStruct.new(body: {
+          double(body: {
             'startAt' => 0,
             'maxResults' => 1,
             'total' => 2,
             'issues' => []
           }.to_json)
         end
         let(:result_2) do
-          OpenStruct.new(body: {
+          double(body: {
             'startAt' => 1,
             'maxResults' => 1,
             'total' => 2,
@@ -132,7 +132,7 @@ class JIRAResourceDelegation < SimpleDelegator # :nodoc:
 
       context 'when there is only one page of results' do
         let(:result_1) do
-          OpenStruct.new(body: {
+          double(body: {
             'startAt' => 0,
             'maxResults' => 2,
             'total' => 2,

spec/jira/resource/field_spec.rb

@@ -1,13 +1,12 @@
 require 'spec_helper'
 
 describe JIRA::Resource::Field do
-  let(:cache) { OpenStruct.new }
-
   let(:client) do
     client = double(options: { rest_base_path: '/jira/rest/api/2' })
     field = JIRA::Resource::FieldFactory.new(client)
     allow(client).to receive(:Field).and_return(field)
-    allow(client).to receive(:cache).and_return(cache)
+    allow(client).to receive(:field_map_cache).and_return(nil)
+    allow(client).to receive(:field_map_cache=)
     # info about all fields on the client
     allow(client.Field).to receive(:all).and_return([
                                                       described_class.new(client,

spec/jira/resource/issue_spec.rb

@@ -7,7 +7,7 @@ class JIRAResourceDelegation < SimpleDelegator # :nodoc:
   let(:client) do
     client = double(options: { rest_base_path: '/jira/rest/api/2' })
     allow(client).to receive(:Field).and_return(JIRA::Resource::FieldFactory.new(client))
-    allow(client).to receive(:cache).and_return(OpenStruct.new)
+    allow(client).to receive(:field_map_cache).and_return(nil)
     client
   end
 

spec/jira/resource/status_spec.rb

@@ -4,7 +4,7 @@
   let(:client) do
     client = double(options: { rest_base_path: '/jira/rest/api/2' })
     allow(client).to receive(:Field).and_return(JIRA::Resource::FieldFactory.new(client))
-    allow(client).to receive(:cache).and_return(OpenStruct.new)
+    allow(client).to receive(:field_map_cache).and_return(nil)
     client
   end