accounts/abi: resolve name conflict for methods starting with a number

accounts/abi/utils.go

@@ -16,7 +16,10 @@
 
 package abi
 
-import "fmt"
+import (
+	"fmt"
+	"unicode"
+)
 
 // ResolveNameConflict returns the next available name for a given thing.
 // This helper can be used for lots of purposes:
@@ -29,11 +32,18 @@ import "fmt"
 //
 // Name conflicts are mostly resolved by adding number suffix. e.g. if the abi contains
 // Methods "send" and "send1", ResolveNameConflict would return "send2" for input "send".
+// If a method name starts with a number an M is prepended (e.g. 1method -> M1method).
+// This will export the method in the ABI, which is okay since a leading number can be interpreted
+// as an uppercase letter.
 func ResolveNameConflict(rawName string, used func(string) bool) string {
-	name := rawName
+	prefixedName := rawName
+	if len(rawName) > 0 && unicode.IsDigit(rune(rawName[0])) {
+		prefixedName = fmt.Sprintf("%s%s", "M", rawName)
+	}
+	name := prefixedName
 	ok := used(name)
 	for idx := 0; ok; idx++ {
-		name = fmt.Sprintf("%s%d", rawName, idx)
+		name = fmt.Sprintf("%s%d", prefixedName, idx)
 		ok = used(name)
 	}
 	return name

accounts/abi/utils_test.go

@@ -0,0 +1,65 @@
+// Copyright 2023 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package abi
+
+import "testing"
+
+func TestResolveNameConflict(t *testing.T) {
+	db := make(map[string]struct{})
+	used := func(s string) bool {
+		_, ok := db[s]
+		return ok
+	}
+
+	var tests = []struct {
+		input  string
+		output string
+	}{
+		{
+			input:  "1method",
+			output: "M1method",
+		},
+		{
+			input:  "1method",
+			output: "M1method0",
+		},
+		{
+			input:  "1method",
+			output: "M1method1",
+		},
+		{
+			input:  "method",
+			output: "method",
+		},
+		{
+			input:  "method",
+			output: "method0",
+		},
+		{
+			input:  "",
+			output: "",
+		},
+	}
+
+	for _, test := range tests {
+		result := ResolveNameConflict(test.input, used)
+		if result != test.output {
+			t.Errorf("resolving name conflict failed, got %v want %v input %v", result, test.output, test.input)
+		}
+		db[result] = struct{}{}
+	}
+}