accounts/abi/bind: add optional block number for calls (#17942)

accounts/abi/bind/base_test.go

@@ -0,0 +1,64 @@
+package bind_test
+
+import (
+	"context"
+	"math/big"
+	"testing"
+
+	ethereum "github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/accounts/abi"
+	"github.com/ethereum/go-ethereum/accounts/abi/bind"
+	"github.com/ethereum/go-ethereum/common"
+)
+
+type mockCaller struct {
+	codeAtBlockNumber       *big.Int
+	callContractBlockNumber *big.Int
+}
+
+func (mc *mockCaller) CodeAt(ctx context.Context, contract common.Address, blockNumber *big.Int) ([]byte, error) {
+	mc.codeAtBlockNumber = blockNumber
+	return []byte{1, 2, 3}, nil
+}
+
+func (mc *mockCaller) CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
+	mc.callContractBlockNumber = blockNumber
+	return nil, nil
+}
+
+func TestPassingBlockNumber(t *testing.T) {
+
+	mc := &mockCaller{}
+
+	bc := bind.NewBoundContract(common.HexToAddress("0x0"), abi.ABI{
+		Methods: map[string]abi.Method{
+			"something": {
+				Name:    "something",
+				Outputs: abi.Arguments{},
+			},
+		},
+	}, mc, nil, nil)
+	var ret string
+
+	blockNumber := big.NewInt(42)
+
+	bc.Call(&bind.CallOpts{BlockNumber: blockNumber}, &ret, "something")
+
+	if mc.callContractBlockNumber != blockNumber {
+		t.Fatalf("CallContract() was not passed the block number")
+	}
+
+	if mc.codeAtBlockNumber != blockNumber {
+		t.Fatalf("CodeAt() was not passed the block number")
+	}
+
+	bc.Call(&bind.CallOpts{}, &ret, "something")
+
+	if mc.callContractBlockNumber != nil {
+		t.Fatalf("CallContract() was passed a block number when it should not have been")
+	}
+
+	if mc.codeAtBlockNumber != nil {
+		t.Fatalf("CodeAt() was passed a block number when it should not have been")
+	}
+}