tools
Diffblue Cover
Diffblue Cover automatically writes and maintains Java and Kotlin unit tests through an IntelliJ plugin, CLI, and CI integrations.
Diffblue Cover analyzes Java and Kotlin code and generates unit tests designed to compile, run, and reflect current code behavior. It can create tests for methods, classes, or entire projects, then update them as code changes.
Developers use the IntelliJ plugin or CLI, while DevOps teams use Cover Pipeline in CI workflows. Cover also includes reporting, test selection, and refactoring tools. A free Community Edition is available; commercial editions require a license. The official pricing page rendered without prices.
Features
- Generates Java and Kotlin unit tests automatically
- Creates tests for methods, classes, or entire projects
- Provides an IntelliJ IDE plugin for one-click test creation
- Offers a scriptable CLI configured for Maven or Gradle projects
- Updates generated tests when code changes
- Integrates with CI pipelines through Cover Pipeline
- Reports coverage, testability, complexity, and testing risk
- Optimizes CI runs by selecting tests related to code changes
Use cases
- Generate unit tests for large or legacy Java codebases
- Maintain regression tests as application code changes
- Add automated test generation to pull-request workflows
- Measure coverage and identify high-risk untested code
- Improve testability through automated code refactoring