Refactor: InstanceInfoと絵文字リアクション利用可能判定テスト (#534)

* Refactor: `InstanceInfo`と絵文字リアクション利用可能判定テスト

* Fix: 新規登録のテストが特定時刻で落ちる問題

spec/models/instance_info_spec.rb

@@ -1,3 +1,44 @@
 # frozen_string_literal: true
 
 require 'rails_helper'
+
+RSpec.describe InstanceInfo do
+  describe '.emoji_reaction_availables_map' do
+    subject { described_class.emoji_reaction_available?('example.com') }
+
+    it 'availables if features contains emoji_reaction' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'mastodon', data: { metadata: { features: ['emoji_reaction'] } })
+      expect(subject).to be true
+    end
+
+    it 'unavailables if features does not contain emoji_reaction' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'mastodon', data: { metadata: { features: ['ohagi'] } })
+      expect(subject).to be false
+    end
+
+    it 'unavailables if features is not valid' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'mastodon', data: { metadata: { features: 'good_for_ohagi' } })
+      expect(subject).to be false
+    end
+
+    it 'unavailables if features is nil' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'mastodon', data: { metadata: { features: nil } })
+      expect(subject).to be false
+    end
+
+    it 'unavailables if mastodon server' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'mastodon')
+      expect(subject).to be false
+    end
+
+    it 'availables if misskey server' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'misskey')
+      expect(subject).to be true
+    end
+
+    it 'unavailables if old mastodon server' do
+      Fabricate(:instance_info, domain: 'example.com', software: 'mastodon', data: { metadata: [] })
+      expect(subject).to be false
+    end
+  end
+end