internal/ethapi: support block number or hash on state-related methods (#19491)

This change adds support for EIP-1898.

rpc/types.go

@@ -18,10 +18,12 @@ package rpc
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"math"
 	"strings"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 )
 
@@ -105,3 +107,94 @@ func (bn *BlockNumber) UnmarshalJSON(data []byte) error {
 func (bn BlockNumber) Int64() int64 {
 	return (int64)(bn)
 }
+
+type BlockNumberOrHash struct {
+	BlockNumber      *BlockNumber `json:"blockNumber,omitempty"`
+	BlockHash        *common.Hash `json:"blockHash,omitempty"`
+	RequireCanonical bool         `json:"requireCanonical,omitempty"`
+}
+
+func (bnh *BlockNumberOrHash) UnmarshalJSON(data []byte) error {
+	type erased BlockNumberOrHash
+	e := erased{}
+	err := json.Unmarshal(data, &e)
+	if err == nil {
+		if e.BlockNumber != nil && e.BlockHash != nil {
+			return fmt.Errorf("cannot specify both BlockHash and BlockNumber, choose one or the other")
+		}
+		bnh.BlockNumber = e.BlockNumber
+		bnh.BlockHash = e.BlockHash
+		bnh.RequireCanonical = e.RequireCanonical
+		return nil
+	}
+	var input string
+	err = json.Unmarshal(data, &input)
+	if err != nil {
+		return err
+	}
+	switch input {
+	case "earliest":
+		bn := EarliestBlockNumber
+		bnh.BlockNumber = &bn
+		return nil
+	case "latest":
+		bn := LatestBlockNumber
+		bnh.BlockNumber = &bn
+		return nil
+	case "pending":
+		bn := PendingBlockNumber
+		bnh.BlockNumber = &bn
+		return nil
+	default:
+		if len(input) == 66 {
+			hash := common.Hash{}
+			err := hash.UnmarshalText([]byte(input))
+			if err != nil {
+				return err
+			}
+			bnh.BlockHash = &hash
+			return nil
+		} else {
+			blckNum, err := hexutil.DecodeUint64(input)
+			if err != nil {
+				return err
+			}
+			if blckNum > math.MaxInt64 {
+				return fmt.Errorf("blocknumber too high")
+			}
+			bn := BlockNumber(blckNum)
+			bnh.BlockNumber = &bn
+			return nil
+		}
+	}
+}
+
+func (bnh *BlockNumberOrHash) Number() (BlockNumber, bool) {
+	if bnh.BlockNumber != nil {
+		return *bnh.BlockNumber, true
+	}
+	return BlockNumber(0), false
+}
+
+func (bnh *BlockNumberOrHash) Hash() (common.Hash, bool) {
+	if bnh.BlockHash != nil {
+		return *bnh.BlockHash, true
+	}
+	return common.Hash{}, false
+}
+
+func BlockNumberOrHashWithNumber(blockNr BlockNumber) BlockNumberOrHash {
+	return BlockNumberOrHash{
+		BlockNumber:      &blockNr,
+		BlockHash:        nil,
+		RequireCanonical: false,
+	}
+}
+
+func BlockNumberOrHashWithHash(hash common.Hash, canonical bool) BlockNumberOrHash {
+	return BlockNumberOrHash{
+		BlockNumber:      nil,
+		BlockHash:        &hash,
+		RequireCanonical: canonical,
+	}
+}

rpc/types_test.go

@@ -20,6 +20,7 @@ import (
 	"encoding/json"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/math"
 )
 
@@ -64,3 +65,60 @@ func TestBlockNumberJSONUnmarshal(t *testing.T) {
 		}
 	}
 }
+
+func TestBlockNumberOrHash_UnmarshalJSON(t *testing.T) {
+	tests := []struct {
+		input    string
+		mustFail bool
+		expected BlockNumberOrHash
+	}{
+		0:  {`"0x"`, true, BlockNumberOrHash{}},
+		1:  {`"0x0"`, false, BlockNumberOrHashWithNumber(0)},
+		2:  {`"0X1"`, false, BlockNumberOrHashWithNumber(1)},
+		3:  {`"0x00"`, true, BlockNumberOrHash{}},
+		4:  {`"0x01"`, true, BlockNumberOrHash{}},
+		5:  {`"0x1"`, false, BlockNumberOrHashWithNumber(1)},
+		6:  {`"0x12"`, false, BlockNumberOrHashWithNumber(18)},
+		7:  {`"0x7fffffffffffffff"`, false, BlockNumberOrHashWithNumber(math.MaxInt64)},
+		8:  {`"0x8000000000000000"`, true, BlockNumberOrHash{}},
+		9:  {"0", true, BlockNumberOrHash{}},
+		10: {`"ff"`, true, BlockNumberOrHash{}},
+		11: {`"pending"`, false, BlockNumberOrHashWithNumber(PendingBlockNumber)},
+		12: {`"latest"`, false, BlockNumberOrHashWithNumber(LatestBlockNumber)},
+		13: {`"earliest"`, false, BlockNumberOrHashWithNumber(EarliestBlockNumber)},
+		14: {`someString`, true, BlockNumberOrHash{}},
+		15: {`""`, true, BlockNumberOrHash{}},
+		16: {``, true, BlockNumberOrHash{}},
+		17: {`"0x0000000000000000000000000000000000000000000000000000000000000000"`, false, BlockNumberOrHashWithHash(common.HexToHash("0x0000000000000000000000000000000000000000000000000000000000000000"), false)},
+		18: {`{"blockHash":"0x0000000000000000000000000000000000000000000000000000000000000000"}`, false, BlockNumberOrHashWithHash(common.HexToHash("0x0000000000000000000000000000000000000000000000000000000000000000"), false)},
+		19: {`{"blockHash":"0x0000000000000000000000000000000000000000000000000000000000000000","requireCanonical":false}`, false, BlockNumberOrHashWithHash(common.HexToHash("0x0000000000000000000000000000000000000000000000000000000000000000"), false)},
+		20: {`{"blockHash":"0x0000000000000000000000000000000000000000000000000000000000000000","requireCanonical":true}`, false, BlockNumberOrHashWithHash(common.HexToHash("0x0000000000000000000000000000000000000000000000000000000000000000"), true)},
+		21: {`{"blockNumber":"0x1"}`, false, BlockNumberOrHashWithNumber(1)},
+		22: {`{"blockNumber":"pending"}`, false, BlockNumberOrHashWithNumber(PendingBlockNumber)},
+		23: {`{"blockNumber":"latest"}`, false, BlockNumberOrHashWithNumber(LatestBlockNumber)},
+		24: {`{"blockNumber":"earliest"}`, false, BlockNumberOrHashWithNumber(EarliestBlockNumber)},
+		25: {`{"blockNumber":"0x1", "blockHash":"0x0000000000000000000000000000000000000000000000000000000000000000"}`, true, BlockNumberOrHash{}},
+	}
+
+	for i, test := range tests {
+		var bnh BlockNumberOrHash
+		err := json.Unmarshal([]byte(test.input), &bnh)
+		if test.mustFail && err == nil {
+			t.Errorf("Test %d should fail", i)
+			continue
+		}
+		if !test.mustFail && err != nil {
+			t.Errorf("Test %d should pass but got err: %v", i, err)
+			continue
+		}
+		hash, hashOk := bnh.Hash()
+		expectedHash, expectedHashOk := test.expected.Hash()
+		num, numOk := bnh.Number()
+		expectedNum, expectedNumOk := test.expected.Number()
+		if bnh.RequireCanonical != test.expected.RequireCanonical ||
+			hash != expectedHash || hashOk != expectedHashOk ||
+			num != expectedNum || numOk != expectedNumOk {
+			t.Errorf("Test %d got unexpected value, want %v, got %v", i, test.expected, bnh)
+		}
+	}
+}