cleaner syntax for choosing a random nation & region in the Local Authority factory, and should_not be_persisted in local_authority_spec

Author: Alistair Davidson

spec/factories/local_authorities.rb

@@ -31,24 +31,8 @@
     gias_code { Array(0..9).sample(3).join }
     official_name { [Faker::Address.city, "Council"].join(" ") }
     short_name { [Faker::Address.city] }
-    region do
-      [
-        "Yorkshire and The Humber",
-        "West Midlands",
-        "East Midlands",
-        "Northern Ireland",
-        "South East",
-        "Wales",
-        nil,
-        "East of England",
-        "Scotland",
-        "North East",
-        "North West",
-        "South West",
-        "London"
-      ].sample
-    end
-    nation { "England" }
+    region { LocalAuthority.regions.keys.sample }
+    nation { LocalAuthority.nations.keys.sample }
     gov_uk_slug do
       ["/", Faker::Address.city.downcase.gsub(/[^A-Z]+/i, "-")].join
     end

spec/models/local_authority_spec.rb

@@ -47,9 +47,9 @@
     end
 
     describe "the result" do
-      it "is not saved" do
-        expect(result.persisted?).to be(false)
-      end
+      subject{ result }
+
+      it { should_not be_persisted }
 
       it "has the expected attributes" do
         expect(result).to have_attributes(