Add mutation for updating user preferences

Allows updating of the issues_sort preference so that we can persist the
sort order in the Vue issues list

Changelog: added

app/graphql/mutations/user_preferences/update.rb

+# frozen_string_literal: true
+
+module Mutations
+  module UserPreferences
+    class Update < BaseMutation
+      graphql_name 'UserPreferencesUpdate'
+
+      argument :issues_sort, Types::IssueSortEnum,
+               required: false,
+               description: 'Sort order for issue lists.'
+
+      field :user_preferences,
+            Types::UserPreferencesType,
+            null: true,
+            description: 'User preferences after mutation.'
+
+      def resolve(**attributes)
+        user_preferences = current_user.user_preference
+        user_preferences.update(attributes)
+
+        {
+          user_preferences: user_preferences.valid? ? user_preferences : nil,
+          errors: errors_on_object(user_preferences)
+        }
+      end
+    end
+  end
+end

app/graphql/types/mutation_type.rb

@@ -121,6 +121,7 @@ module Types
     mount_mutation Mutations::Namespace::PackageSettings::Update
     mount_mutation Mutations::Groups::Update
     mount_mutation Mutations::UserCallouts::Create
+    mount_mutation Mutations::UserPreferences::Update
     mount_mutation Mutations::Packages::Destroy
     mount_mutation Mutations::Packages::DestroyFile
     mount_mutation Mutations::Echo

app/graphql/types/user_preferences_type.rb

+# frozen_string_literal: true
+
+module Types
+  # rubocop: disable Graphql/AuthorizeTypes
+  # Only used to render the current user's own preferences
+  class UserPreferencesType < BaseObject
+    graphql_name 'UserPreferences'
+
+    field :issues_sort, Types::IssueSortEnum,
+      description: 'Sort order for issue lists.',
+      null: true
+
+    def issues_sort
+      object.issues_sort.to_sym
+    end
+  end
+end

doc/api/graphql/reference/index.md

@@ -4885,6 +4885,25 @@ Input type: `UserCalloutCreateInput`
 | <a id="mutationusercalloutcreateerrors"></a>`errors` | [`[String!]!`](#string) | Errors encountered during execution of the mutation. |
 | <a id="mutationusercalloutcreateusercallout"></a>`userCallout` | [`UserCallout!`](#usercallout) | User callout dismissed. |
 
+### `Mutation.userPreferencesUpdate`
+
+Input type: `UserPreferencesUpdateInput`
+
+#### Arguments
+
+| Name | Type | Description |
+| ---- | ---- | ----------- |
+| <a id="mutationuserpreferencesupdateclientmutationid"></a>`clientMutationId` | [`String`](#string) | A unique identifier for the client performing the mutation. |
+| <a id="mutationuserpreferencesupdateissuessort"></a>`issuesSort` | [`IssueSort`](#issuesort) | Sort order for issue lists. |
+
+#### Fields
+
+| Name | Type | Description |
+| ---- | ---- | ----------- |
+| <a id="mutationuserpreferencesupdateclientmutationid"></a>`clientMutationId` | [`String`](#string) | A unique identifier for the client performing the mutation. |
+| <a id="mutationuserpreferencesupdateerrors"></a>`errors` | [`[String!]!`](#string) | Errors encountered during execution of the mutation. |
+| <a id="mutationuserpreferencesupdateuserpreferences"></a>`userPreferences` | [`UserPreferences`](#userpreferences) | User preferences after mutation. |
+
 ### `Mutation.vulnerabilityConfirm`
 
 Input type: `VulnerabilityConfirmInput`
@@ -15731,6 +15750,14 @@ fields relate to interactions between the two entities.
 | ---- | ---- | ----------- |
 | <a id="userpermissionscreatesnippet"></a>`createSnippet` | [`Boolean!`](#boolean) | Indicates the user can perform `create_snippet` on this resource. |
 
+### `UserPreferences`
+
+#### Fields
+
+| Name | Type | Description |
+| ---- | ---- | ----------- |
+| <a id="userpreferencesissuessort"></a>`issuesSort` | [`IssueSort`](#issuesort) | Sort order for issue lists. |
+
 ### `UserStatus`
 
 #### Fields

spec/graphql/types/user_preferences_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Types::UserPreferencesType do
+  specify { expect(described_class.graphql_name).to eq('UserPreferences') }
+
+  it 'exposes the expected fields' do
+    expected_fields = %i[
+      issues_sort
+    ]
+
+    expect(described_class).to have_graphql_fields(*expected_fields)
+  end
+end

spec/requests/api/graphql/mutations/user_preferences/update_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Mutations::UserPreferences::Update do
+  include GraphqlHelpers
+
+  let_it_be(:current_user) { create(:user) }
+
+  let(:sort_value) { 'TITLE_ASC' }
+
+  let(:input) do
+    {
+      'issuesSort' => sort_value
+    }
+  end
+
+  let(:mutation) { graphql_mutation(:userPreferencesUpdate, input) }
+  let(:mutation_response) { graphql_mutation_response(:userPreferencesUpdate) }
+
+  context 'when user has no existing preference' do
+    it 'creates the user preference record' do
+      post_graphql_mutation(mutation, current_user: current_user)
+
+      expect(response).to have_gitlab_http_status(:success)
+      expect(mutation_response['userPreferences']['issuesSort']).to eq(sort_value)
+
+      expect(current_user.user_preference.persisted?).to eq(true)
+      expect(current_user.user_preference.issues_sort).to eq(Types::IssueSortEnum.values[sort_value].value.to_s)
+    end
+  end
+
+  context 'when user has existing preference' do
+    before do
+      current_user.create_user_preference!(issues_sort: Types::IssueSortEnum.values['TITLE_DESC'].value)
+    end
+
+    it 'updates the existing value' do
+      post_graphql_mutation(mutation, current_user: current_user)
+
+      current_user.user_preference.reload
+
+      expect(response).to have_gitlab_http_status(:success)
+      expect(mutation_response['userPreferences']['issuesSort']).to eq(sort_value)
+
+      expect(current_user.user_preference.issues_sort).to eq(Types::IssueSortEnum.values[sort_value].value.to_s)
+    end
+  end
+end