abi/base: return error for pending call error (#24649)

If a pending contract call errors, return that error right away rather
than ignoring it to allow an error somewhere else. This is helpful for
callers to know if perhaps a call failed because of the context deadline
being expired. This change mirrors the behavior of non-pending contract
calls.

accounts/abi/bind/base.go

@@ -172,7 +172,10 @@ func (c *BoundContract) Call(opts *CallOpts, results *[]interface{}, method stri
 			return ErrNoPendingState
 		}
 		output, err = pb.PendingCallContract(ctx, msg)
-		if err == nil && len(output) == 0 {
+		if err != nil {
+			return err
+		}
+		if len(output) == 0 {
 			// Make sure we have a contract to operate on, and bail out otherwise.
 			if code, err = pb.PendingCodeAt(ctx, c.address); err != nil {
 				return err

accounts/abi/bind/base_test.go

@@ -76,30 +76,42 @@ func (mt *mockTransactor) SendTransaction(ctx context.Context, tx *types.Transac
 }
 
 type mockCaller struct {
-	codeAtBlockNumber         *big.Int
-	callContractBlockNumber   *big.Int
-	pendingCodeAtCalled       bool
-	pendingCallContractCalled bool
+	codeAtBlockNumber       *big.Int
+	callContractBlockNumber *big.Int
+	callContractBytes       []byte
+	callContractErr         error
+	codeAtBytes             []byte
+	codeAtErr               error
 }
 
 func (mc *mockCaller) CodeAt(ctx context.Context, contract common.Address, blockNumber *big.Int) ([]byte, error) {
 	mc.codeAtBlockNumber = blockNumber
-	return []byte{1, 2, 3}, nil
+	return mc.codeAtBytes, mc.codeAtErr
 }
 
 func (mc *mockCaller) CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
 	mc.callContractBlockNumber = blockNumber
-	return nil, nil
+	return mc.callContractBytes, mc.callContractErr
 }
 
-func (mc *mockCaller) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) {
+type mockPendingCaller struct {
+	*mockCaller
+	pendingCodeAtBytes        []byte
+	pendingCodeAtErr          error
+	pendingCodeAtCalled       bool
+	pendingCallContractCalled bool
+	pendingCallContractBytes  []byte
+	pendingCallContractErr    error
+}
+
+func (mc *mockPendingCaller) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) {
 	mc.pendingCodeAtCalled = true
-	return nil, nil
+	return mc.pendingCodeAtBytes, mc.pendingCodeAtErr
 }
 
-func (mc *mockCaller) PendingCallContract(ctx context.Context, call ethereum.CallMsg) ([]byte, error) {
+func (mc *mockPendingCaller) PendingCallContract(ctx context.Context, call ethereum.CallMsg) ([]byte, error) {
 	mc.pendingCallContractCalled = true
-	return nil, nil
+	return mc.pendingCallContractBytes, mc.pendingCallContractErr
 }
 
 type mockBlockHashCaller struct {
@@ -124,7 +136,11 @@ func (mc *mockBlockHashCaller) CallContractAtHash(ctx context.Context, call ethe
 
 func TestPassingBlockNumber(t *testing.T) {
 
-	mc := &mockCaller{}
+	mc := &mockPendingCaller{
+		mockCaller: &mockCaller{
+			codeAtBytes: []byte{1, 2, 3},
+		},
+	}
 
 	bc := bind.NewBoundContract(common.HexToAddress("0x0"), abi.ABI{
 		Methods: map[string]abi.Method{