writing-tests

To write JUnit 5 tests for the IntelliJ codebase, annotate new test classes with @TestApplication instead of extending legacy test case classes, then use companion objects to hold shared project or module fixtures for reuse across test methods.

Managing test fixtures in IntelliJ tests involves holding shared project and module fixtures in companion objects. For disposable resources, apply the @TestDisposable annotation to ensure proper lifecycle handling and automated cleanup during test teardown.

To run tests in the Event Dispatch Thread (EDT) within the IntelliJ codebase, apply specific testing annotations designed to enforce EDT execution. This ensures UI-related test logic executes safely on the correct thread without manual invokeLater calls.

Use JUnit 5 lifecycle annotations like @BeforeAll, @AfterAll, @BeforeEach, and @AfterEach in IntelliJ tests to standardize setup and teardown operations. These annotations manage test state initialization and resource cleanup consistently across both Java and Kotlin codebases.

Standard JUnit 5 patterns for registry and system properties in IntelliJ tests require following specific codebase guidelines. The standardized approach specifies exact patterns for safely accessing and modifying registry entries and system properties during test execution.

Standardizing test structure with showcase patterns in IntelliJ ensures consistent test quality and practices across Kotlin and Java codebases. Referencing showcase tests provides concrete examples of proper fixture bootstrapping, lifecycle management, and EDT considerations.