feat: add methods signature parser, decouple ABI parser

abi.go

@@ -0,0 +1,49 @@
+package celoutils
+
+import (
+	"io"
+
+	"github.com/celo-org/celo-blockchain/accounts/abi"
+)
+
+type (
+	ParsedABI struct {
+		EventSignatures  []EventSignature
+		MethodSignatures []MethodSignature
+	}
+)
+
+func ParseABI(abiReader io.Reader) (*ParsedABI, error) {
+	abi, err := abi.JSON(abiReader)
+	if err != nil {
+		return nil, err
+	}
+
+	var (
+		eventSignatures   []EventSignature
+		methodsSignatures []MethodSignature
+	)
+
+	for _, v := range abi.Events {
+		eventSignature, err := EventSignatureFromString(v.Sig)
+		if err != nil {
+			return nil, err
+		}
+
+		eventSignatures = append(eventSignatures, eventSignature)
+	}
+
+	for _, v := range abi.Methods {
+		methodSignature, err := MethodSignatureFromString(v.Sig)
+		if err != nil {
+			return nil, err
+		}
+
+		methodsSignatures = append(methodsSignatures, methodSignature)
+	}
+
+	return &ParsedABI{
+		EventSignatures:  eventSignatures,
+		MethodSignatures: methodsSignatures,
+	}, nil
+}

abi_test.go

@@ -0,0 +1,57 @@
+package celoutils
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestParseABI(t *testing.T) {
+	//    contract T {
+	//      event received(address sender, uint amount, bytes memo);
+	//      event receivedAddr(address sender);
+	//      function receive(bytes memo) external payable {
+	//        received(msg.sender, msg.value, memo);
+	//        receivedAddr(msg.sender);
+	//      }
+	//    }
+	// https://www.4byte.directory/event-signatures
+	// 253837 	received(address,uint256,bytes) 	0x75fd880d39c1daf53b6547ab6cb59451fc6452d27caa90e5b6649dd8293b9eed
+	// 253838 	receivedAddr(address) 	0x46923992397eac56cf13058aced2a1871933622717e27b24eabc13bf9dd329c8
+	eventSignatures := []EventSignature{
+		{
+			Signature: "received(address,uint256,bytes)",
+			Hash:      "0x75fd880d39c1daf53b6547ab6cb59451fc6452d27caa90e5b6649dd8293b9eed",
+		},
+		{
+			Signature: "receivedAddr(address)",
+			Hash:      "0x46923992397eac56cf13058aced2a1871933622717e27b24eabc13bf9dd329c8",
+		},
+	}
+
+	methodSignatures := []MethodSignature{
+		{
+			Signature: "receive(bytes)",
+			Hash:      "a69b6ed0",
+		},
+	}
+
+	want := &ParsedABI{
+		EventSignatures:  eventSignatures,
+		MethodSignatures: methodSignatures,
+	}
+
+	json := `[{"constant":false,"inputs":[{"name":"memo","type":"bytes"}],"name":"receive","outputs":[],"payable":true,"stateMutability":"payable","type":"function"},{"anonymous":false,"inputs":[{"indexed":false,"name":"sender","type":"address"},{"indexed":false,"name":"amount","type":"uint256"},{"indexed":false,"name":"memo","type":"bytes"}],"name":"received","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"sender","type":"address"}],"name":"receivedAddr","type":"event"}]`
+	got, err := ParseABI(strings.NewReader(json))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(got.EventSignatures, want.EventSignatures) {
+		t.Errorf("Event signatures slices should be equal, got %v and %v", got, want)
+	}
+
+	if !reflect.DeepEqual(got.MethodSignatures, want.MethodSignatures) {
+		t.Errorf("Method signatures slices should be equal, got %v and %v", got, want)
+	}
+}

event.go

@@ -1,10 +1,8 @@
 package celoutils
 
 import (
-	"io"
 	"strings"
 
-	"github.com/celo-org/celo-blockchain/accounts/abi"
 	"github.com/grassrootseconomics/w3-celo"
 )
 
@@ -15,7 +13,7 @@ type (
 	}
 )
 
-func EventSignatureHash(eventSignature string) (EventSignature, error) {
+func EventSignatureFromString(eventSignature string) (EventSignature, error) {
 	event, err := w3.NewEvent(strings.TrimSuffix(eventSignature, ";"))
 	if err != nil {
 		return EventSignature{}, err
@@ -26,23 +24,3 @@ func EventSignatureHash(eventSignature string) (EventSignature, error) {
 		Hash:      event.Topic0.Hex(),
 	}, nil
 }
-
-func EventSignatureHashesFromABI(abiReader io.Reader) ([]EventSignature, error) {
-	abi, err := abi.JSON(abiReader)
-	if err != nil {
-		return nil, err
-	}
-
-	var eventSignatures []EventSignature
-
-	for _, v := range abi.Events {
-		eventSignatureHash, err := EventSignatureHash(v.Sig)
-		if err != nil {
-			return nil, err
-		}
-
-		eventSignatures = append(eventSignatures, eventSignatureHash)
-	}
-
-	return eventSignatures, nil
-}

event_test.go

@@ -1,8 +1,6 @@
 package celoutils
 
 import (
-	"reflect"
-	"strings"
 	"testing"
 )
 
@@ -38,7 +36,7 @@ func TestEventSignatureHash(t *testing.T) {
 		{
 			name: "Transfer Event variant 3",
 			args: args{
-				event: "Transfer(address indexed _from, address indexed _to, uint256 _value)",
+				event: "Transfer(address indexed _from, address indexed _to, uint256 _value);",
 			},
 			want: EventSignature{
 				Signature: "Transfer(address,address,uint256)",
@@ -48,7 +46,7 @@ func TestEventSignatureHash(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := EventSignatureHash(tt.args.event)
+			got, err := EventSignatureFromString(tt.args.event)
 			if err != nil {
 				t.Errorf("EventSignatureHash() got error: %v", err)
 			}
@@ -58,37 +56,3 @@ func TestEventSignatureHash(t *testing.T) {
 		})
 	}
 }
-
-func TestEventSignatureHashesFromABI(t *testing.T) {
-	//    contract T {
-	//      event received(address sender, uint amount, bytes memo);
-	//      event receivedAddr(address sender);
-	//      function receive(bytes memo) external payable {
-	//        received(msg.sender, msg.value, memo);
-	//        receivedAddr(msg.sender);
-	//      }
-	//    }
-	// https://www.4byte.directory/event-signatures
-	// 253837 	received(address,uint256,bytes) 	0x75fd880d39c1daf53b6547ab6cb59451fc6452d27caa90e5b6649dd8293b9eed
-	// 253838 	receivedAddr(address) 	0x46923992397eac56cf13058aced2a1871933622717e27b24eabc13bf9dd329c8
-	want := []EventSignature{
-		{
-			Signature: "received(address,uint256,bytes)",
-			Hash:      "0x75fd880d39c1daf53b6547ab6cb59451fc6452d27caa90e5b6649dd8293b9eed",
-		},
-		{
-			Signature: "receivedAddr(address)",
-			Hash:      "0x46923992397eac56cf13058aced2a1871933622717e27b24eabc13bf9dd329c8",
-		},
-	}
-
-	json := `[{"constant":false,"inputs":[{"name":"memo","type":"bytes"}],"name":"receive","outputs":[],"payable":true,"stateMutability":"payable","type":"function"},{"anonymous":false,"inputs":[{"indexed":false,"name":"sender","type":"address"},{"indexed":false,"name":"amount","type":"uint256"},{"indexed":false,"name":"memo","type":"bytes"}],"name":"received","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"sender","type":"address"}],"name":"receivedAddr","type":"event"}]`
-	got, err := EventSignatureHashesFromABI(strings.NewReader(json))
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("Slices should be equal, got %v and %v", got, want)
-	}
-}

method.go

@@ -0,0 +1,26 @@
+package celoutils
+
+import (
+	"encoding/hex"
+
+	"github.com/grassrootseconomics/w3-celo"
+)
+
+type (
+	MethodSignature struct {
+		Signature string
+		Hash      string
+	}
+)
+
+func MethodSignatureFromString(methodSignature string) (MethodSignature, error) {
+	method, err := w3.NewFunc(methodSignature, "")
+	if err != nil {
+		return MethodSignature{}, err
+	}
+
+	return MethodSignature{
+		Signature: method.Signature,
+		Hash:      hex.EncodeToString(method.Selector[:]),
+	}, nil
+}

method_test.go

@@ -0,0 +1,41 @@
+package celoutils
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestMethodSignatureFromString(t *testing.T) {
+	type args struct {
+		methodSignature string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    MethodSignature
+		wantErr bool
+	}{
+		{
+			name: "Transfer Method",
+			args: args{
+				methodSignature: "transfer(address, uint256)",
+			},
+			want: MethodSignature{
+				Signature: "transfer(address,uint256)",
+				Hash:      "a9059cbb",
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := MethodSignatureFromString(tt.args.methodSignature)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("MethodSignatureFromString() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("MethodSignatureFromString() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}