Add Comprehensive GraphQL API Tests

[devin-ai-integration]

Add Comprehensive GraphQL API Tests

Summary

This PR adds a complete test suite for the GraphQL API layer of the Spring Boot RealWorld Example App. The tests cover mutations (user registration, article CRUD, comments), queries (articles, profiles, feeds), data fetchers, and error handling scenarios. The test structure follows the existing REST API test patterns and includes 10 new test classes with comprehensive documentation.

⚠️ Important Note: The tests currently compile successfully but are failing at runtime due to Spring context configuration issues with the DGS framework. The tests need additional configuration work to properly initialize the GraphQL context. The existing REST API tests continue to pass.

Review & Testing Checklist for Human

• CRITICAL: Understand that these tests do NOT currently pass (23 of 33 tests fail with Spring context/bean definition errors). Decide whether to merge as documentation of intended test coverage or require fixes first.
• Review the test structure and approach - verify it aligns with DGS framework best practices for testing GraphQL endpoints
• Manually test the GraphQL API endpoints (user mutations, article queries, etc.) to ensure the actual GraphQL functionality works correctly in the application
• Consider whether additional Spring Boot test configuration or DGS-specific test setup is needed (e.g., test slices, additional bean definitions)
• Review the test coverage scope - does it cover all critical GraphQL operations adequately?

Test Plan

1. Run ./gradlew test --tests "io.spring.api.*" to verify existing REST API tests still pass ✅ (confirmed passing)
2. Run ./gradlew test --tests "io.spring.graphql.*" to see current test failures
3. Manually test GraphQL mutations and queries using a GraphQL client (e.g., GraphiQL, Postman)
4. If merging despite failing tests, create follow-up ticket to fix Spring context configuration

Notes

Test Files Added:

• Base classes: GraphQLTestBase.java, GraphQLIntegrationTestBase.java
• Mutation tests: UserMutationTest.java, ArticleMutationTest.java, CommentMutationTest.java
• Query tests: ArticleQueryTest.java, ProfileQueryTest.java
• Data fetcher tests: ArticleDatafetcherTest.java
• Error handling: GraphQLErrorHandlingTest.java
• Documentation: README.md with test patterns and usage

Why Tests Are Failing:
The tests use @SpringBootTest with DgsAutoConfiguration and specific component classes, but the Spring context is not properly initializing all required beans (particularly NoSuchBeanDefinitionException and UnsatisfiedDependencyException errors). The DGS framework testing approach may need adjustment - possibly requiring full application context or different test slice annotations.

Session Info:

• Requested by: Shawn Azman (shawn@cognition.ai) / @ShawnAzman
• Session: https://app.devin.ai/sessions/19f5d3baf7af41ac86b174d21922a5e0

[devin-ai-integration]

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