account/abi/bind/v2: fix TestDeploymentWithOverrides (#32212)

The root cause of the flaky test was a nonce conflict caused by async
contract deployments.

This solution defines a custom deployer with automatic nonce management.

accounts/abi/bind/v2/lib.go

@@ -28,6 +28,7 @@ package bind
 
 import (
 	"errors"
+	"math/big"
 
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/accounts/abi"
@@ -241,3 +242,27 @@ func DefaultDeployer(opts *TransactOpts, backend ContractBackend) DeployFn {
 		return addr, tx, nil
 	}
 }
+
+// DeployerWithNonceAssignment is basically identical to DefaultDeployer,
+// but it additionally tracks the nonce to enable automatic assignment.
+//
+// This is especially useful when deploying multiple contracts
+// from the same address — whether they are independent contracts
+// or part of a dependency chain that must be deployed in order.
+func DeployerWithNonceAssignment(opts *TransactOpts, backend ContractBackend) DeployFn {
+	var pendingNonce int64
+	if opts.Nonce != nil {
+		pendingNonce = opts.Nonce.Int64()
+	}
+	return func(input []byte, deployer []byte) (common.Address, *types.Transaction, error) {
+		if pendingNonce != 0 {
+			opts.Nonce = big.NewInt(pendingNonce)
+		}
+		addr, tx, err := DeployContract(opts, deployer, backend, input)
+		if err != nil {
+			return common.Address{}, nil, err
+		}
+		pendingNonce = int64(tx.Nonce() + 1)
+		return addr, tx, nil
+	}
+}

accounts/abi/bind/v2/lib_test.go

@@ -65,6 +65,14 @@ func makeTestDeployer(backend simulated.Client) func(input, deployer []byte) (co
 	return bind.DefaultDeployer(bind.NewKeyedTransactor(testKey, chainId), backend)
 }
 
+// makeTestDeployerWithNonceAssignment is similar to makeTestDeployer,
+// but it returns a deployer that automatically tracks nonce,
+// enabling the deployment of multiple contracts from the same account.
+func makeTestDeployerWithNonceAssignment(backend simulated.Client) func(input, deployer []byte) (common.Address, *types.Transaction, error) {
+	chainId, _ := backend.ChainID(context.Background())
+	return bind.DeployerWithNonceAssignment(bind.NewKeyedTransactor(testKey, chainId), backend)
+}
+
 // test that deploying a contract with library dependencies works,
 // verifying by calling method on the deployed contract.
 func TestDeploymentLibraries(t *testing.T) {
@@ -80,7 +88,7 @@ func TestDeploymentLibraries(t *testing.T) {
 		Contracts: []*bind.MetaData{&nested_libraries.C1MetaData},
 		Inputs:    map[string][]byte{nested_libraries.C1MetaData.ID: constructorInput},
 	}
-	res, err := bind.LinkAndDeploy(deploymentParams, makeTestDeployer(bindBackend.Client))
+	res, err := bind.LinkAndDeploy(deploymentParams, makeTestDeployerWithNonceAssignment(bindBackend.Client))
 	if err != nil {
 		t.Fatalf("err: %+v\n", err)
 	}
@@ -122,7 +130,7 @@ func TestDeploymentWithOverrides(t *testing.T) {
 	deploymentParams := &bind.DeploymentParams{
 		Contracts: nested_libraries.C1MetaData.Deps,
 	}
-	res, err := bind.LinkAndDeploy(deploymentParams, makeTestDeployer(bindBackend))
+	res, err := bind.LinkAndDeploy(deploymentParams, makeTestDeployerWithNonceAssignment(bindBackend))
 	if err != nil {
 		t.Fatalf("err: %+v\n", err)
 	}