accounts/abi/bind: Accept function ptr parameter (#19755)

* accounts/abi/bind: Accept function ptr parameter

They are translated as [24]byte

* Add Java template version

* accounts/abi/bind: fix merge issue

* Fix CI

accounts/abi/bind/bind.go

@@ -44,7 +44,7 @@ const (
 // to be used as is in client code, but rather as an intermediate struct which
 // enforces compile time type safety and naming convention opposed to having to
 // manually maintain hard coded strings that break on runtime.
-func Bind(types []string, abis []string, bytecodes []string, pkg string, lang Lang) (string, error) {
+func Bind(types []string, abis []string, bytecodes []string, fsigs []map[string]string, pkg string, lang Lang) (string, error) {
 	// Process each individual contract requested binding
 	contracts := make(map[string]*tmplContract)
 
@@ -125,6 +125,9 @@ func Bind(types []string, abis []string, bytecodes []string, pkg string, lang La
 			Transacts:   transacts,
 			Events:      events,
 		}
+		if len(fsigs) > i {
+			contracts[types[i]].FuncSigs = fsigs[i]
+		}
 	}
 	// Generate the contract template data content and render it
 	data := &tmplData{
@@ -180,8 +183,7 @@ func bindBasicTypeGo(kind abi.Type) string {
 	case abi.BytesTy:
 		return "[]byte"
 	case abi.FunctionTy:
-		// todo(rjl493456442)
-		return ""
+		return "[24]byte"
 	default:
 		// string, bool types
 		return kind.String()
@@ -240,8 +242,7 @@ func bindBasicTypeJava(kind abi.Type) string {
 	case abi.StringTy:
 		return "String"
 	case abi.FunctionTy:
-		// todo(rjl493456442)
-		return ""
+		return "byte[24]"
 	default:
 		return kind.String()
 	}

accounts/abi/bind/template.go

@@ -29,6 +29,7 @@ type tmplContract struct {
 	Type        string                 // Type name of the main contract binding
 	InputABI    string                 // JSON ABI used as the input to generate the binding from
 	InputBin    string                 // Optional EVM bytecode used to denetare deploy code from
+	FuncSigs    map[string]string      // Optional map: string signature -> 4-byte signature
 	Constructor abi.Method             // Contract constructor for deploy parametrization
 	Calls       map[string]*tmplMethod // Contract calls that only read state data
 	Transacts   map[string]*tmplMethod // Contract calls that write state data
@@ -92,6 +93,15 @@ var (
 	// {{.Type}}ABI is the input ABI used to generate the binding from.
 	const {{.Type}}ABI = "{{.InputABI}}"
 
+	{{if $contract.FuncSigs}}
+		// {{.Type}}FuncSigs maps the 4-byte function signature to its string representation.
+		var {{.Type}}FuncSigs = map[string]string{
+			{{range $strsig, $binsig := .FuncSigs}}
+				"{{$binsig}}": "{{$strsig}}",
+			{{end}}
+		}
+	{{end}}
+
 	{{if .InputBin}}
 		// {{.Type}}Bin is the compiled bytecode used for deploying new contracts.
 		const {{.Type}}Bin = ` + "`" + `{{.InputBin}}` + "`" + `
@@ -464,12 +474,23 @@ const tmplSourceJava = `
 package {{.Package}};
 
 import org.ethereum.geth.*;
+import java.util.*;
 
 {{range $contract := .Contracts}}
 public class {{.Type}} {
 	// ABI is the input ABI used to generate the binding from.
 	public final static String ABI = "{{.InputABI}}";
-
+	{{if $contract.FuncSigs}}
+		// {{.Type}}FuncSigs maps the 4-byte function signature to its string representation.
+		public final static Map<String, String> {{.Type}}FuncSigs;
+		static {
+			Hashtable<String, String> temp = new Hashtable<String, String>();
+			{{range $strsig, $binsig := .FuncSigs}}
+				temp.put("{{$binsig}}", "{{$strsig}}");
+			{{end}}
+			{{.Type}}FuncSigs = Collections.unmodifiableMap(temp);
+		}
+	{{end}}
 	{{if .InputBin}}
 	// BYTECODE is the compiled bytecode used for deploying new contracts.
 	public final static String BYTECODE = "0x{{.InputBin}}";

cmd/abigen/main.go

@@ -78,6 +78,7 @@ func main() {
 		abis  []string
 		bins  []string
 		types []string
+		sigs  []map[string]string
 	)
 	if *solFlag != "" || *vyFlag != "" || *abiFlag == "-" {
 		// Generate the list of types to exclude from binding
@@ -121,6 +122,7 @@ func main() {
 			}
 			abis = append(abis, string(abi))
 			bins = append(bins, contract.Code)
+			sigs = append(sigs, contract.Hashes)
 
 			nameParts := strings.Split(name, ":")
 			types = append(types, nameParts[len(nameParts)-1])
@@ -151,7 +153,7 @@ func main() {
 		types = append(types, kind)
 	}
 	// Generate the contract binding
-	code, err := bind.Bind(types, abis, bins, *pkgFlag, lang)
+	code, err := bind.Bind(types, abis, bins, sigs, *pkgFlag, lang)
 	if err != nil {
 		fmt.Printf("Failed to generate ABI binding: %v\n", err)
 		os.Exit(-1)

common/compiler/helpers.go

@@ -27,9 +27,10 @@ var versionRegexp = regexp.MustCompile(`([0-9]+)\.([0-9]+)\.([0-9]+)`)
 
 // Contract contains information about a compiled contract, alongside its code and runtime code.
 type Contract struct {
-	Code        string       `json:"code"`
-	RuntimeCode string       `json:"runtime-code"`
-	Info        ContractInfo `json:"info"`
+	Code        string            `json:"code"`
+	RuntimeCode string            `json:"runtime-code"`
+	Info        ContractInfo      `json:"info"`
+	Hashes      map[string]string `json:"hashes"`
 }
 
 // ContractInfo contains information about a compiled contract, including access

common/compiler/solidity.go

@@ -39,6 +39,7 @@ type solcOutput struct {
 		BinRuntime                                  string `json:"bin-runtime"`
 		SrcMapRuntime                               string `json:"srcmap-runtime"`
 		Bin, SrcMap, Abi, Devdoc, Userdoc, Metadata string
+		Hashes                                      map[string]string
 	}
 	Version string
 }
@@ -49,7 +50,7 @@ func (s *Solidity) makeArgs() []string {
 		"--optimize", // code optimizer switched on
 	}
 	if s.Major > 0 || s.Minor > 4 || s.Patch > 6 {
-		p[1] += ",metadata"
+		p[1] += ",metadata,hashes"
 	}
 	return p
 }
@@ -161,6 +162,7 @@ func ParseCombinedJSON(combinedJSON []byte, source string, languageVersion strin
 		contracts[name] = &Contract{
 			Code:        "0x" + info.Bin,
 			RuntimeCode: "0x" + info.BinRuntime,
+			Hashes:      info.Hashes,
 			Info: ContractInfo{
 				Source:          source,
 				Language:        "Solidity",