remove proptest-specific encoding logic from Header

[Rjected]

Describe the feature

This code needs to be removed, along with the similar looking code in that file:

reth/crates/primitives/src/header.rs

Lines 521 to 572 in e03544b

	if started_len - buf.len() < rlp_head.payload_length {
	if buf.first().map(|b| *b == EMPTY_LIST_CODE).unwrap_or_default() {
	buf.advance(1)
	} else {
	this.base_fee_per_gas = Some(u64::decode(buf)?);
	}
	}
	// Withdrawals root for post-shanghai headers
	if started_len - buf.len() < rlp_head.payload_length {
	if buf.first().map(|b| *b == EMPTY_STRING_CODE).unwrap_or_default() {
	buf.advance(1)
	} else {
	this.withdrawals_root = Some(Decodable::decode(buf)?);
	}
	}
	// Blob gas used and excess blob gas for post-cancun headers
	if started_len - buf.len() < rlp_head.payload_length {
	if buf.first().map(|b| *b == EMPTY_LIST_CODE).unwrap_or_default() {
	buf.advance(1)
	} else {
	this.blob_gas_used = Some(u64::decode(buf)?);
	}
	}
	if started_len - buf.len() < rlp_head.payload_length {
	if buf.first().map(|b| *b == EMPTY_LIST_CODE).unwrap_or_default() {
	buf.advance(1)
	} else {
	this.excess_blob_gas = Some(u64::decode(buf)?);
	}
	}
	// Decode parent beacon block root. If new fields are added, the above pattern will need to
	// be repeated and placeholders decoded. Otherwise, it's impossible to tell _which_
	// fields are missing. This is mainly relevant for contrived cases where a header is
	// created at random, for example:
	// * A header is created with a withdrawals root, but no base fee. Shanghai blocks are
	// post-London, so this is technically not valid. However, a tool like proptest would
	// generate a block like this.
	if started_len - buf.len() < rlp_head.payload_length {
	this.parent_beacon_block_root = Some(B256::decode(buf)?);
	}
	let consumed = started_len - buf.len();
	if consumed != rlp_head.payload_length {
	return Err(alloy_rlp::Error::ListLengthMismatch {
	expected: rlp_head.payload_length,
	got: consumed,
	})
	}

We need to fix the proptest::arbitrary::Arbitrary implementation to only include i.e. excess_blob_gas if all previous fork specific fields exist.

reth/crates/primitives/src/header.rs

Lines 616 to 633 in e03544b

	#[cfg(any(test, feature = "arbitrary"))]
	impl proptest::arbitrary::Arbitrary for SealedHeader {
	type Parameters = ();
	fn arbitrary_with(_: Self::Parameters) -> Self::Strategy {
	use proptest::prelude::{any, Strategy};
	any::<(Header, BlockHash)>().prop_map(move |(header, _)| header.seal_slow()).boxed()
	}
	type Strategy = proptest::strategy::BoxedStrategy<SealedHeader>;
	}
	#[cfg(any(test, feature = "arbitrary"))]
	impl<'a> arbitrary::Arbitrary<'a> for SealedHeader {
	fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
	Ok(Header::arbitrary(u)?.seal_slow())
	}
	}

Additional context

No response

[supernovahs]

Let me take this

[Rjected]

Let me take this

hey! feel free to submit a PR and I'll review