From 4f7123c3c0807040da8fc38949405c51ef07f45d Mon Sep 17 00:00:00 2001
From: Daniel Liu <liudaniel@qq.com>
Date: Tue, 14 Jan 2025 10:56:13 +0800
Subject: [PATCH] accounts/abi/bind/backends: return errors instead of panic
 (#24242)

---
 accounts/abi/bind/backends/simulated.go | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/accounts/abi/bind/backends/simulated.go b/accounts/abi/bind/backends/simulated.go
index 0fff0f8fb5..2abe3c3539 100644
--- a/accounts/abi/bind/backends/simulated.go
+++ b/accounts/abi/bind/backends/simulated.go
@@ -703,7 +703,6 @@ func (b *SimulatedBackend) callContract(ctx context.Context, call ethereum.CallM
 }
 
 // SendTransaction updates the pending block to include the given transaction.
-// It panics if the transaction is invalid.
 func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transaction) error {
 	b.mu.Lock()
 	defer b.mu.Unlock()
@@ -711,17 +710,17 @@ func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx *types.Transa
 	// Get the last block
 	block, err := b.blockByHash(ctx, b.pendingBlock.ParentHash())
 	if err != nil {
-		panic("could not fetch parent")
+		return fmt.Errorf("could not fetch parent")
 	}
 	// Check transaction validity
 	signer := types.MakeSigner(b.blockchain.Config(), block.Number())
 	sender, err := types.Sender(signer, tx)
 	if err != nil {
-		panic(fmt.Errorf("invalid transaction: %v", err))
+		return fmt.Errorf("invalid transaction: %v", err)
 	}
 	nonce := b.pendingState.GetNonce(sender)
 	if tx.Nonce() != nonce {
-		panic(fmt.Errorf("invalid transaction nonce: got %d, want %d", tx.Nonce(), nonce))
+		return fmt.Errorf("invalid transaction nonce: got %d, want %d", tx.Nonce(), nonce)
 	}
 	// Include tx in chain
 	blocks, receipts := core.GenerateChain(b.config, block, b.blockchain.Engine(), b.database, 1, func(number int, block *core.BlockGen) {