From 326341511336b84ff7870210156a04235be0f4b4 Mon Sep 17 00:00:00 2001
From: Matthias Seitz <matthias.seitz@outlook.de>
Date: Thu, 17 Oct 2024 12:57:04 +0200
Subject: [PATCH] feat: add helper to eip155 variant

---
 crates/primitives/src/signature/parity.rs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/crates/primitives/src/signature/parity.rs b/crates/primitives/src/signature/parity.rs
index c8415f1f0..5cf2d1680 100644
--- a/crates/primitives/src/signature/parity.rs
+++ b/crates/primitives/src/signature/parity.rs
@@ -76,6 +76,25 @@ impl Parity {
         }
     }
 
+    /// Applies a check to the [`Parity::Eip155`] v value if this instance is a [`Parity::Eip155`].
+    ///
+    /// Returns [`Ok`] if the instance is not [`Parity::Eip155`]
+    pub fn ensure_eip155<F, E>(&self, f: F) -> Result<(), E>
+    where
+        F: FnOnce(u64) -> Result<(), E>,
+    {
+        if let Self::Eip155(v) = self {
+            f(*v)
+        } else {
+            Ok(())
+        }
+    }
+
+    /// Returns true if this instance is a [`Parity::Eip155`]
+    pub const fn is_eip155(&self) -> bool {
+        matches!(self, Self::Eip155(_))
+    }
+
     /// Return the y-parity as a boolean.
     pub const fn y_parity(&self) -> bool {
         match self {