chain-spec-builder: Automatically cross check --para-id flag with ParachainInfo genesis state.

[skunert]

Currently we do no check for correctness of para IDs in the chain-spec-builder.

Example

Executing this command will create a simple chain spec.

chain-spec-builder create -p 300 -c polkadot --runtime my_runtime.compact.compressed.wasm named-preset development

Ecerpt from chain_spec.json:

{
   ...
   "para_id": 300
   "genesis": {
      ...
      "runtimeGenesis": {
         ...
         "parachainInfo": {
            "parachainId": 1000
         }
      }
   }
}

There is a clear mismatch between the genesis state of the parachain info pallet and the para id in the client spec. This is expected, as the genesis state is coming from the runtime.

Solution

The chain-spec-builder could make an exception for the ParachainInfo crate and automatically align the para ids. I can not think of a use-case where it makes sense to have a mismatch there. We can print out a log that highlights that the Id has been adjusted.

[bkchr]

The proper solution for the problem is this #2116 plus this #75.

No hacky solution around making the chain spec generator do things it should not be doing.