Run `integrity_test` in externalities

[ggwpez]

We should probably run all of then inside externalities. In the past I was concerned about unintended consequences, but it just annoyed us again in: paritytech/polkadot#6957

Since there a parameter type was configured to be storage instead of const, so it would fail outside externalities.

[ggwpez]

Note: There are cases were we explicitly want to run something outside of externalities.
For example complicated weight annotations in pallet alliance use config constants.
These could be factored out into helper functions and ran outside of externalities as a test to ensure that they dont access state.
Otherwise there is a chance that someone configures them to a storage parameter_type!…

[bkchr]

I don't see any problem in using storage parameter_type! if there is a justification. Before we started to make all of them "const' all of these parameters where stored in the storage. However, it doesn't make any sense to read something from the storage that isn't ever changing. But some implementations may have a reason to have some value dynamic.

[ggwpez]

So you mean that reading storage in weight annotations is fine? Or how does your comment relate to mine?
Someone on SE pointed out that Polkadot does this.

[bkchr]

I mean reading storage for the weight needs to be done with a lot of caution to not open a DDOS door.

The linked weight looks wrong as the weight should not depend on the number of digests.

[atenjin]

In fact in our project, we are using a storage to config the max weight..
So we are blocked at here (integrity_test not in Externalities).

Though you may not agree our practice that using a storage to config the weight, we are using substrate not for public using, in fact just in some corner case. So I agree this may have a hidden danger for DDOS, but I think we know what we are doing for now.

Anyway, even we do not consider about the weight, I think for the integrity_test, we may also need to access some storage in the test, so I think let the integrity_test in Externalities is necessary.

[ggwpez]

You can always create externalities in the integrity_test, like here https://github.com/paritytech/substrate/pull/13092/files so this should not block you.
Although we can also run the test in externalities per default, the only catch would be that the genesis state is not configurable, which could be weird.

[atenjin]

@ggwpez oh thanks, but in fact our panic appears from transaction-payment pallet 🤣🤣🤣
so add it as default for all pallet is more better.