feat(eips): Make prague field an enum

crates/eips/src/eip7685.rs

@@ -77,6 +77,35 @@ impl Requests {
     }
 }
 
+/// A list of requests or a precomputed requests hash.
+///
+/// For testing purposes, the `Hash` variant stores a precomputed requests hash. This can be useful
+///   when the exact contents of the requests are unnecessary, and only a consistent hash value is
+/// needed   to simulate the presence of requests without holding actual data.
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+pub enum RequestsOrHash {
+    /// Stores a list of requests, allowing for dynamic requests hash calculation.
+    Requests(Requests),
+    /// Stores a precomputed requests hash, used primarily for testing.
+    Hash(B256),
+}
+
+impl RequestsOrHash {
+    /// Returns the requests hash for the enum instance.
+    ///
+    /// - If the instance contains a list of requests, this function calculates the hash using
+    ///   `requests_hash` of the [`Requests`] struct.
+    /// - If it contains a precomputed hash, it returns that hash directly.
+    #[cfg(feature = "sha2")]
+    pub fn requests_hash(&self) -> B256 {
+        match self {
+            Self::Requests(requests) => requests.requests_hash(),
+            Self::Hash(precomputed_hash) => *precomputed_hash,
+        }
+    }
+}
 #[cfg(test)]
 mod tests {
     use super::*;

crates/rpc-types-engine/src/sidecar.rs

@@ -2,7 +2,7 @@
 
 use crate::{CancunPayloadFields, MaybeCancunPayloadFields};
 use alloc::vec::Vec;
-use alloy_eips::eip7685::Requests;
+use alloy_eips::eip7685::{Requests, RequestsOrHash};
 use alloy_primitives::B256;
 
 /// Container type for all available additional `newPayload` request parameters that are not present
@@ -15,7 +15,7 @@ pub struct ExecutionPayloadSidecar {
     cancun: MaybeCancunPayloadFields,
     /// The EIP-7685 requests provided as additional request params to `engine_newPayloadV4` that
     /// are not present in the `ExecutionPayload`.
-    prague: Option<Requests>,
+    prague: Option<RequestsOrHash>,
 }
 
 impl ExecutionPayloadSidecar {
@@ -30,7 +30,7 @@ impl ExecutionPayloadSidecar {
     }
 
     /// Creates a new instance post prague for `engine_newPayloadV4`
-    pub fn v4(cancun: CancunPayloadFields, requests: Requests) -> Self {
+    pub fn v4(cancun: CancunPayloadFields, requests: RequestsOrHash) -> Self {
         Self { cancun: cancun.into(), prague: Some(requests) }
     }
 
@@ -51,6 +51,20 @@ impl ExecutionPayloadSidecar {
 
     /// Returns the EIP-7685 requests
     pub const fn requests(&self) -> Option<&Requests> {
-        self.prague.as_ref()
+        if let Some(RequestsOrHash::Requests(ref requests)) = self.prague {
+            Some(requests)
+        } else {
+            None
+        }
+    }
+
+    /// Calculates or retrieves the requests hash.
+    ///
+    /// - If the `prague` field contains a list of requests, it calculates the requests hash
+    ///   dynamically.
+    /// - If it contains a precomputed hash (used for testing), it returns that hash directly.
+
+    pub fn requests_hash(&self) -> B256 {
+        self.prague.as_ref().unwrap().requests_hash()
     }
 }