From be09550a510ffd0171fb2219bf433b035a06afc7 Mon Sep 17 00:00:00 2001
From: christn <c.k.e.koopmann@gmail.com>
Date: Wed, 27 Mar 2024 14:32:54 +0800
Subject: [PATCH] Adjust calc_gas_limit to be a more direct translation of the
 geth version to check if that fixes differing responses

---
 src/rpc/utils.rs | 55 ++++++++++++++++--------------------------------
 1 file changed, 18 insertions(+), 37 deletions(-)

diff --git a/src/rpc/utils.rs b/src/rpc/utils.rs
index 6439f75..646291c 100644
--- a/src/rpc/utils.rs
+++ b/src/rpc/utils.rs
@@ -1,7 +1,5 @@
 use crate::rpc::result::internal_rpc_err;
 use jsonrpsee::core::RpcResult;
-use reth_tracing::tracing;
-use std::cmp::Ordering;
 
 pub fn compare_values<T: std::cmp::PartialEq + std::fmt::Display>(
     name: &str,
@@ -28,44 +26,27 @@ const MIN_GAS_LIMIT: u64 = 5000;
 // the target if the baseline gas is lower.
 // Ported from: https://github.com/flashbots/builder/blob/03ee71cf0a344397204f65ff6d3a917ee8e06724/core/utils/gas_limit.go#L8
 // Reference implementation: https://eips.ethereum.org/EIPS/eip-1559#specification
-pub fn calc_gas_limit(parent_gas_limit: u64, desired_limit: u64) -> u64 {
+pub fn calc_gas_limit(parent_gas_limit: u64, mut desired_limit: u64) -> u64 {
     // TODO: Understand why 1 is subtracted here
     let delta = parent_gas_limit / GAS_LIMIT_BOUND_DIVISOR - 1;
-    let desired_or_min_limit = std::cmp::max(desired_limit, MIN_GAS_LIMIT);
-    match parent_gas_limit.cmp(&desired_or_min_limit) {
-        Ordering::Less => {
-            let max_acceptable_limit = parent_gas_limit + delta;
-            tracing::debug!(
-                parent_gas_limit,
-                delta,
-                desired_limit,
-                desired_or_min_limit,
-                max_acceptable_limit,
-                "Parent gas limit is less than desired/min limit"
-            );
-            std::cmp::min(max_acceptable_limit, desired_or_min_limit)
-        }
-        Ordering::Greater => {
-            let min_acceptable_limit = parent_gas_limit - delta;
-            tracing::debug!(
-                parent_gas_limit,
-                delta,
-                desired_limit,
-                desired_or_min_limit,
-                min_acceptable_limit,
-                "Parent gas limit is greater than desired/min limit"
-            );
-            std::cmp::max(min_acceptable_limit, desired_or_min_limit)
+    let mut limit = parent_gas_limit;
+
+    if desired_limit < MIN_GAS_LIMIT {
+        desired_limit = MIN_GAS_LIMIT;
+    }
+
+    // If we're outside our allowed gas range, we try to hone towards them
+    if limit < desired_limit {
+        limit = parent_gas_limit + delta;
+        if limit > desired_limit {
+            limit = desired_limit;
         }
-        Ordering::Equal => {
-            tracing::debug!(
-                parent_gas_limit,
-                delta,
-                desired_limit,
-                desired_or_min_limit,
-                "Parent gas limit is equal to desired/min limit"
-            );
-            parent_gas_limit
+    } else if limit > desired_limit {
+        limit = parent_gas_limit - delta;
+        if limit < desired_limit {
+            limit = desired_limit;
         }
     }
+
+    limit
 }