feat: spoof balances

crates/rbuilder/src/bin/debug-bench-machine.rs

@@ -78,6 +78,7 @@ async fn main() -> eyre::Result<()> {
         blocklist: Default::default(),
         excess_blob_gas: block_data.excess_blob_gas,
         spec_id: SpecId::LATEST,
+        backtest_balances_to_spoof: None,
     };
 
     let orders = block_data

crates/rbuilder/src/building/mod.rs

@@ -73,6 +73,9 @@ pub struct BlockBuildingContext {
     pub excess_blob_gas: Option<u64>,
     /// Version of the EVM that we are going to use
     pub spec_id: SpecId,
+    // An optional Vec of a tuple of addresses and balances to spoof during simulation
+    // [!SAFETY!] Only use in backtesting
+    pub backtest_balances_to_spoof: Option<Vec<(Address, u128)>>,
 }
 
 impl BlockBuildingContext {
@@ -138,6 +141,7 @@ impl BlockBuildingContext {
             extra_data,
             excess_blob_gas,
             spec_id,
+            backtest_balances_to_spoof: None,
         }
     }
 
@@ -235,6 +239,7 @@ impl BlockBuildingContext {
                 .excess_blob_gas
                 .map(|b| b as u64),
             spec_id,
+            backtest_balances_to_spoof: None,
         }
     }
 

crates/rbuilder/src/building/order_commit.rs

@@ -411,8 +411,17 @@ impl<'a, 'b, 'c, Tracer: SimulationTracer> PartialBlockFork<'a, 'b, 'c, Tracer>
             .with_env(Box::new(env))
             .with_db(db.as_mut())
             .with_external_context(&mut rbuilder_inspector)
-            .append_handler_register(inspector_handle_register)
-            .build();
+            .append_handler_register(inspector_handle_register);
+
+        if let Some(balances_to_increment) = &ctx.backtest_balances_to_spoof {
+            evm = evm.modify_db(|db| {
+                for (addr, balance) in balances_to_increment {
+                    let _ = db.increment_balances([(*addr, *balance)]);
+                }
+            });
+        }
+
+        let mut evm = evm.build();
         let res = match evm.transact() {
             Ok(res) => res,
             Err(err) => match err {