Add Vat tune transformer

pkg/transformers/shared/constants.go

@@ -57,6 +57,7 @@ var (
 	tendMethod                = GetSolidityMethodSignature(FlipperABI, "tend")
 	vatInitMethod             = GetSolidityMethodSignature(VatABI, "init")
 	vatTollMethod             = GetSolidityMethodSignature(VatABI, "toll")
+	vatTuneMethod             = GetSolidityMethodSignature(VatABI, "tune")
 
 	BiteSignature                = GetEventSignature(biteMethod)
 	DealSignature                = GetLogNoteSignature(dealMethod)
@@ -78,4 +79,5 @@ var (
 	TendFunctionSignature        = GetLogNoteSignature(tendMethod)
 	VatInitSignature             = GetLogNoteSignature(vatInitMethod)
 	VatTollSignature             = GetLogNoteSignature(vatTollMethod)
+	VatTuneSignature             = GetLogNoteSignature(vatTuneMethod)
 )

pkg/transformers/shared/utilities.go

@@ -32,3 +32,15 @@ func BigIntToString(value *big.Int) string {
 		return result
 	}
 }
+
+func GetDataBytesAtIndex(n int, logData []byte) []byte {
+	switch {
+	case n == -1:
+		return logData[len(logData)-DataItemLength:]
+	case n == -2:
+		return logData[len(logData)-(2*DataItemLength) : len(logData)-DataItemLength]
+	case n == -3:
+		return logData[len(logData)-(3*DataItemLength) : len(logData)-(2*DataItemLength)]
+	}
+	return []byte{}
+}

pkg/transformers/shared/utilities_test.go

@@ -0,0 +1,49 @@
+package shared_test
+
+import (
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
+	"math/big"
+)
+
+var _ = Describe("Shared utilities", func() {
+	Describe("getting data at index", func() {
+		It("gets bytes for the last index in log data", func() {
+			logData := hexutil.MustDecode("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")
+			bigIntBytes := big.NewInt(987654321).Bytes()
+			// big.Int.Bytes() does not include zero padding, but bytes in data index are of fixed length and include zero padding
+			expected := []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+			expected = append(expected, bigIntBytes...)
+
+			actual := shared.GetDataBytesAtIndex(-1, logData)
+
+			Expect(expected[:]).To(Equal(actual))
+		})
+
+		It("gets bytes for the second-to-last index in log data", func() {
+			logData := hexutil.MustDecode("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")
+			bigIntBytes := big.NewInt(123456789).Bytes()
+			expected := []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+			expected = append(expected, bigIntBytes...)
+
+			actual := shared.GetDataBytesAtIndex(-2, logData)
+
+			Expect(expected[:]).To(Equal(actual))
+		})
+
+		It("gets bytes for the third-to-last index in log data", func() {
+			logData := hexutil.MustDecode("0x000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000c45dd6471a66616b6520696c6b0000000000000000000000000000000000000000000000007d7bee5fcfd8028cf7b00876c5b1421c800561a6000000000000000000000000a3e37186e017747dba34042e83e3f76ad3cce9b00000000000000000000000000f243e26db94b5426032e6dfa6007802dea2a61400000000000000000000000000000000000000000000000000000000000000000000000000000000075bcd15000000000000000000000000000000000000000000000000000000003ade68b1")
+			addressBytes := common.HexToAddress("0x0F243E26db94B5426032E6DFA6007802Dea2a614").Bytes()
+			// common.address.Bytes() returns [20]byte{}, need [32]byte{}
+			expected := append(addressBytes, []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}...)
+
+			actual := shared.GetDataBytesAtIndex(-3, logData)
+
+			Expect(expected[:]).To(Equal(actual))
+		})
+	})
+})