accounts/abi/bind: add utilities for waiting on transactions

The need for these functions comes up in code that actually deploys and
uses contracts. As of this commit, they can be used with both
SimulatedBackend and ethclient.

SimulatedBackend gains some additional methods in the process and is now
safe for concurrent use.

1 files changed, 10 insertions, 0 deletions

diff --git a/accounts/abi/bind/backend.go b/accounts/abi/bind/backend.go
index 3d38f87cd..a4e90914f 100644
--- a/accounts/abi/bind/backend.go
+++ b/accounts/abi/bind/backend.go
@@ -35,6 +35,10 @@ var (
 	// This error is raised when attempting to perform a pending state action
 	// on a backend that doesn't implement PendingContractCaller.
 	ErrNoPendingState = errors.New("backend does not support pending state")
+
+	// This error is returned by WaitDeployed if contract creation leaves an
+	// empty contract behind.
+	ErrNoCodeAfterDeploy = errors.New("no contract code after deployment")
 )
 
 // ContractCaller defines the methods needed to allow operating with contract on a read
@@ -48,6 +52,12 @@ type ContractCaller interface {
 	CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error)
 }
 
+// DeployBackend wraps the operations needed by WaitMined and WaitDeployed.
+type DeployBackend interface {
+	TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
+	CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error)
+}
+
 // PendingContractCaller defines methods to perform contract calls on the pending state.
 // Call will try to discover this interface when access to the pending state is requested.
 // If the backend does not support the pending state, Call returns ErrNoPendingState.