There's a lot of clutter to support these little enums and helper functions and mocks. It makes the fixture's true logic harder to tease out.

The biggest of these is StepRunner. This should be separated out.

The ServiceStateMachineTest fixture should just make instances of these types and manipulate these instances. They don't need their definitions inlined into the fixture class.

ServiceStateMachineTest: give more descriptive names to these while we're at it:

struct Data

enum IngressState

enum IngressMode