🐛 Fix return value of #add_provider_to_user on User instance

  * Before, the method would return an instance of Authentication,
    instead of the original intention to return an instance of the
    current user.

  * Arguably the instance of the current user is not very useful,
    as it's already known 🤷‍♂, but at least it matches the current
    examples.

Author: mtomov

lib/sorcery/model/submodules/external.rb

@@ -95,15 +95,13 @@ module InstanceMethods
           def add_provider_to_user(provider, uid)
             authentications = sorcery_config.authentications_class.name.demodulize.underscore.pluralize
             # first check to see if user has a particular authentication already
-            if sorcery_adapter.find_authentication_by_oauth_credentials(authentications, provider, uid).nil?
-              user = send(authentications).build(sorcery_config.provider_uid_attribute_name => uid,
+            return false if sorcery_adapter.find_authentication_by_oauth_credentials(authentications, provider, uid)
+
+            authentication = send(authentications).build(sorcery_config.provider_uid_attribute_name => uid,
                                                  sorcery_config.provider_attribute_name => provider)
-              user.sorcery_adapter.save(validate: false)
-            else
-              user = false
-            end
+            authentication.sorcery_adapter.save(validate: false)
 
-            user
+            self
           end
         end
       end

spec/shared_examples/user_oauth_shared_examples.rb

@@ -29,5 +29,28 @@
       external_user
       expect(User.load_from_provider(:twitter, 980_342)).to be_nil
     end
+
+    describe "#add_provider_to_user" do
+      let!(:user) { create_new_user }
+
+      subject { user.add_provider_to_user(:twitter, 123) }
+
+      context "when a provider is successfully added" do
+        it "returns an instance of user" do
+          user = subject
+          expect(user).to be_kind_of(User)
+          expect(user.authentications.count).to eq 1
+        end
+      end
+
+      context "when a provider already exists" do
+        let(:user) { create_new_external_user :twitter }
+
+        it "does not create a new authentication and returns false" do
+          expect { subject }.not_to change(Authentication, :count)
+          expect(subject).to be false
+        end
+      end
+    end
   end
 end