Env::from_snapshot no longer creates an Env consistent with Env::default

[leighmcculloch]

What version are you using?

v20.0.0-rc2

What did you do?

Serialized an Env to a LedgerSnapshot, then reloaded it into an Env.

What did you expect to see?

The Env loaded with the same state as if Env::default() had been called and the ledger state loaded, meaning auth recording is off, and a default base prng seed is set.

What did you see instead?

An Env loaded with auth recording on and no default base prng seed.

Discussion

It looks like when we added new behavior, and removed auth recording, in Env::default:

rs-soroban-sdk/soroban-sdk/src/env.rs

Lines 524 to 532 in 0992413

	env_impl
	.set_source_account(xdr::AccountId(xdr::PublicKey::PublicKeyTypeEd25519(
	xdr::Uint256(random()),
	)))
	.unwrap();
	env_impl
	.set_diagnostic_level(internal::DiagnosticLevel::Debug)
	.unwrap();
	env_impl.set_base_prng_seed([0; 32]).unwrap();

We forgot to make the same changes in Env::from_snapshot:

rs-soroban-sdk/soroban-sdk/src/env.rs

Lines 1216 to 1231 in 0992413

	pub fn from_snapshot(s: LedgerSnapshot) -> Env {
	let info = s.ledger_info();
	let rs = Rc::new(s.clone());
	let storage = internal::storage::Storage::with_recording_footprint(rs.clone());
	let budget = internal::budget::Budget::default();
	let env_impl = internal::EnvImpl::with_storage_and_budget(storage, budget.clone());
	env_impl.switch_to_recording_auth(true).unwrap();
	let env = Env {
	env_impl,
	snapshot: Some(rs.clone()),
	};
	env.ledger().set(info);
	env
	}

We should probably have Env::from_snapshot and Env::default share the same setup logic and the same storage type, where default is just an empty LedgerSnapshot.

[leighmcculloch]

@brson You're welcome to take this, especially if it's blocking your work.

[brson]

Yep. I will try to fix it.