Adjustments based on review feedback

Reworded some spec descriptions.
Removed a shared example as it was used in one place.
Other minor refactors.
Avoids error when namespace is nil.

ee/lib/ee/gitlab/repository_size_checker.rb

@@ -27,7 +27,7 @@ module EE
       def additional_repo_storage_available?
         return false unless ::Gitlab::CurrentSettings.automatic_purchased_storage_allocation?
 
-        namespace.additional_repo_storage_by_namespace_enabled?
+        !!namespace&.additional_repo_storage_by_namespace_enabled?
       end
 
       def total_repository_size_excess

ee/spec/helpers/ee/namespace_storage_limit_alert_helper_spec.rb

@@ -228,9 +228,11 @@ RSpec.describe EE::NamespaceStorageLimitAlertHelper do
       before do
         allow(::Gitlab).to receive(:dev_env_or_com?).and_return(is_dev_or_com)
         stub_application_setting(automatic_purchased_storage_allocation: auto_storage_allocation_enabled)
-        stub_feature_flags(namespace_storage_limit: namespace_storage_limit_enabled)
-        stub_feature_flags(additional_repo_storage_by_namespace: additional_storage_enabled)
-        stub_feature_flags(buy_storage_link: buy_storage_link_enabled)
+        stub_feature_flags(
+          namespace_storage_limit: namespace_storage_limit_enabled,
+          additional_repo_storage_by_namespace: additional_storage_enabled,
+          buy_storage_link: buy_storage_link_enabled
+        )
       end
 
       it { is_expected.to eq(result) }

ee/spec/lib/ee/gitlab/repository_size_checker_spec.rb

@@ -23,30 +23,54 @@ RSpec.describe Gitlab::RepositorySizeChecker do
   before do
     allow(Gitlab::CurrentSettings).to receive(:automatic_purchased_storage_allocation?).and_return(gitlab_setting_enabled)
 
-    allow(namespace).to receive(:total_repository_size_excess).and_return(total_repository_size_excess.megabytes)
-  end
-
-  shared_examples 'original logic (without size excess and additional storage)' do
-    include_examples 'checker size above limit'
-    include_examples 'checker size above limit (with additional storage, that would bring it under the limit)'
-    include_examples 'checker size not over limit'
+    allow(namespace).to receive(:total_repository_size_excess).and_return(total_repository_size_excess.megabytes) if namespace
   end
 
   describe '#above_size_limit?' do
+    shared_examples 'original logic (additional storage not considered)' do
+      include_examples 'checker size above limit'
+      include_examples 'checker size not over limit'
+
+      context 'when over the default limit but would be under the limit if additional storage was enabled' do
+        let(:current_size) { 100 }
+        let(:additional_purchased_storage) { 60 }
+
+        it 'returns true' do
+          expect(subject.above_size_limit?).to eq(true)
+        end
+      end
+    end
+
     context 'when enabled is false' do
       let(:enabled) { false }
 
-      it 'returns false' do
-        expect(subject.above_size_limit?).to eq(false)
+      context 'when size is under the limit' do
+        it 'returns false' do
+          expect(subject.above_size_limit?).to eq(false)
+        end
+      end
+
+      context 'when size is above the limit' do
+        let(:current_size) { 100 }
+
+        it 'returns false' do
+          expect(subject.above_size_limit?).to eq(false)
+        end
       end
     end
 
-    include_examples 'original logic (without size excess and additional storage)'
+    include_examples 'original logic (additional storage not considered)'
 
     context 'when Gitlab app setting for automatic purchased storage allocation is not enabled' do
       let(:gitlab_setting_enabled) { false }
 
-      include_examples 'original logic (without size excess and additional storage)'
+      include_examples 'original logic (additional storage not considered)'
+    end
+
+    context 'when namespace is nil' do
+      let(:namespace) { nil }
+
+      include_examples 'original logic (additional storage not considered)'
     end
 
     context 'with feature flag :namespace_storage_limit disabled' do
@@ -88,7 +112,7 @@ RSpec.describe Gitlab::RepositorySizeChecker do
         stub_feature_flags(additional_repo_storage_by_namespace: false)
       end
 
-      include_examples 'original logic (without size excess and additional storage)'
+      include_examples 'original logic (additional storage not considered)'
     end
   end
 
@@ -101,6 +125,12 @@ RSpec.describe Gitlab::RepositorySizeChecker do
       include_examples 'checker size exceeded'
     end
 
+    context 'when namespace is nil' do
+      let(:namespace) { nil }
+
+      include_examples 'checker size exceeded'
+    end
+
     context 'with feature flag :namespace_storage_limit disabled' do
       before do
         stub_feature_flags(namespace_storage_limit: false)

ee/spec/models/ee/namespace/root_excess_storage_size_spec.rb

@@ -111,6 +111,10 @@ RSpec.describe EE::Namespace::RootExcessStorageSize do
       it { is_expected.to eq(false) }
     end
 
+    context 'with feature flags (:namespace_storage_limit & :additional_repo_storage_by_namespace) enabled' do
+      it { is_expected.to eq(false) }
+    end
+
     context 'with feature flag :namespace_storage_limit disabled' do
       before do
         stub_feature_flags(namespace_storage_limit: false)

spec/support/shared_examples/lib/gitlab/repository_size_checker_shared_examples.rb

@@ -10,17 +10,6 @@ RSpec.shared_examples 'checker size above limit' do
   end
 end
 
-RSpec.shared_examples 'checker size above limit (with additional storage, that would bring it under the limit)' do
-  context 'when size is above the limit' do
-    let(:current_size) { 100 }
-    let(:additional_purchased_storage) { 60 }
-
-    it 'returns true' do
-      expect(subject.above_size_limit?).to eq(true)
-    end
-  end
-end
-
 RSpec.shared_examples 'checker size not over limit' do
   it 'returns false when not over the limit' do
     expect(subject.above_size_limit?).to eq(false)