Improve Block Production Unit Tests

[mh0lt]

Rationale

In testing #17363 it seems like we missed this becuase we don't have a unit test which covers internal block state. More generally I think we don't have enough unit tests for the mining flow and for its use via the engine_api in particular.

I think this a just a legacy of the fact that most of the base blockchain unit tests where writtent before the engine api existed and therefor drive the flow by using a Mock Sentry.

Now we have a EngineAPITester I think we can refactor some or all of the tests to use this api and for some of them use the EngineAPI FCU+Block Builder process to poulate the chain. This will mean that this code gets excercized in our unit tests rather than just during runtime.

I think we also need to add tests for specific scenarios one of which is:

• Create block whith transaction which access syscontract state.

Implementation

• Adjust/Duplicate chain tests to populate chains via the engine api
• Add test to excercize block creation with internal state access
• Add additional tests as required

[VBulikov]

mh0lt added Imp2 as Importance

[yperbasis]

See also #14337

[VBulikov]

yperbasis changed Importance from Imp2 to Imp1

[VBulikov]

yperbasis added 03/12/2025 as Start date

[VBulikov]

yperbasis added 12/02/2026 as Due date

[yperbasis]

@taratorio did some work on this front (TestAssembleBlock) in PR #19010.