Validate community clinic ODS code doesn't match organisation

The generic clinic location will use the ODS code of the organisation,
so the community clinics cannot use this ODS code as there's a unique
index on the column.

app/models/location.rb

@@ -66,8 +66,12 @@ class Location < ApplicationRecord
     validates :team, presence: true
   end
 
+  with_options if: :community_clinic? do
+    validates :ods_code, exclusion: { in: :organisation_ods_code }
+  end
+
   with_options if: :generic_clinic? do
-    validates :ods_code, comparison: { equal_to: :organisation_ods_code }
+    validates :ods_code, inclusion: { in: :organisation_ods_code }
   end
 
   with_options if: :gp_practice? do
@@ -93,6 +97,6 @@ def dfe_number
   private
 
   def organisation_ods_code
-    team&.organisation&.ods_code
+    [team&.organisation&.ods_code]
   end
 end

spec/models/location_spec.rb

@@ -51,14 +51,22 @@
     it { should validate_presence_of(:name) }
 
     context "with a community clinic" do
-      subject(:location) { build(:community_clinic, ods_code: "abc") }
+      subject(:location) { build(:community_clinic, organisation:) }
+
+      let(:organisation) { create(:organisation) }
 
       it { should_not validate_presence_of(:gias_establishment_number) }
       it { should_not validate_presence_of(:gias_local_authority_code) }
 
       it { should validate_presence_of(:ods_code) }
       it { should validate_uniqueness_of(:ods_code).ignoring_case_sensitivity }
 
+      it do
+        expect(location).to validate_exclusion_of(:ods_code).in_array(
+          [organisation.ods_code]
+        )
+      end
+
       it { should_not validate_presence_of(:urn) }
       it { should validate_uniqueness_of(:urn) }
     end
@@ -75,8 +83,8 @@
       it { should validate_uniqueness_of(:ods_code).ignoring_case_sensitivity }
 
       it do
-        expect(location).to validate_comparison_of(:ods_code).is_equal_to(
-          organisation.ods_code
+        expect(location).to validate_inclusion_of(:ods_code).in_array(
+          [organisation.ods_code]
         )
       end