Unblock domain service specs/refactor (#2867)

* Add spec for unblock domain service

* Refactor UnblockDomainService

spec/services/unblock_domain_service_spec.rb

@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe UnblockDomainService do
+  subject { described_class.new }
+
+  describe 'call' do
+    before do
+      @silenced = Fabricate(:account, domain: 'example.com', silenced: true)
+      @suspended = Fabricate(:account, domain: 'example.com', suspended: true)
+      @domain_block = Fabricate(:domain_block, domain: 'example.com')
+    end
+
+    context 'without retroactive' do
+      it 'removes the domain block' do
+        subject.call(@domain_block, false)
+        expect_deleted_domain_block
+      end
+    end
+
+    context 'with retroactive' do
+      it 'unsilences accounts and removes block' do
+        @domain_block.update(severity: :silence)
+
+        subject.call(@domain_block, true)
+        expect_deleted_domain_block
+        expect(@silenced.reload.silenced).to be false
+        expect(@suspended.reload.suspended).to be true
+      end
+
+      it 'unsuspends accounts and removes block' do
+        @domain_block.update(severity: :suspend)
+
+        subject.call(@domain_block, true)
+        expect_deleted_domain_block
+        expect(@suspended.reload.suspended).to be false
+        expect(@silenced.reload.silenced).to be true
+      end
+    end
+  end
+
+  def expect_deleted_domain_block
+    expect { @domain_block.reload }.to raise_error(ActiveRecord::RecordNotFound)
+  end
+end