Overview

Although it is typically discouraged, having a way to order tests is useful to some people. The JUnit 4 @FixMethodOrder annotation specifically and deliberately makes it impossible to implement a simple ordering scheme, forcing users who want/need this to resort to method names like test245_ensureReasonableTestName().

Proposal

• The minimal "requirement" would be to allow users to write their own MethodSorter for @FixMethodOrder
• A reasonable implementation would be to allow @FixMethodOrder(ORDERED), and then @Order(integer) to specify individual tests. Tests could be run from smallest number to highest, with non-annotated methods having a default of 0. Methods with the same order could be run in parallel; different order tiers could not.

Related Issues

• Introduce first-class support for scenario tests #48
• Introduce mechanism for inter-test dependencies #607
• Running tests in certain order #884
• Introduce declarative mechanism for ordering extensions registered via @RegisterExtension #1707

Deliverables

• Introduce a mechanism for ordering testable methods within JUnit Jupiter.
• Validate collection of methods ordered by an extension; log warning or error if methods were added or removed.
• Introduce built-in support for alphanumeric ordering.
• Introduce built-in support for @Order based ordering.
• Introduce built-in support for random ordering.
• Introduce Configuration Parameter for setting the seed used in random ordering.
• Test ordering support in top-level classes.
• Test ordering of @Test, @TestFactory and @TestTemplate methods.
• Test ordering support in @Nested classes.
• Test ordering support in conjunction with parallel test execution.
• Extract junit.jupiter.execution.order.random.seed constant and document it.
• Write Javadoc for all new types.
• Update @API declarations for types with changed visibility, etc.
• Document new features in User Guide.
• Document new features in Release Notes.

Out of Scope

• ❌ Consider introducing a mechanism for ordering tests with the JUnit Platform -- potentially at a later date in conjunction with a separate dedicated issue.