1 files changed, 90 insertions, 0 deletions
diff --git a/accounts/abi/method.go b/accounts/abi/method.go
new file mode 100644
index 0000000..9cceaba
--- /dev/null
+++ b/accounts/abi/method.go
@@ -0,0 +1,90 @@
+// Copyright 2015 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 (
+	"fmt"
+	"strings"
+
+	"github.com/ava-labs/go-ethereum/crypto"
+)
+
+// Method represents a callable given a `Name` and whether the method is a constant.
+// If the method is `Const` no transaction needs to be created for this
+// particular Method call. It can easily be simulated using a local VM.
+// For example a `Balance()` method only needs to retrieve something
+// from the storage and therefore requires no Tx to be send to the
+// network. A method such as `Transact` does require a Tx and thus will
+// be flagged `false`.
+// Input specifies the required input parameters for this gives method.
+type Method struct {
+	// Name is the method name used for internal representation. It's derived from
+	// the raw name and a suffix will be added in the case of a function overload.
+	//
+	// e.g.
+	// There are two functions have same name:
+	// * foo(int,int)
+	// * foo(uint,uint)
+	// The method name of the first one will be resolved as foo while the second one
+	// will be resolved as foo0.
+	Name string
+	// RawName is the raw method name parsed from ABI.
+	RawName string
+	Const   bool
+	Inputs  Arguments
+	Outputs Arguments
+}
+
+// Sig returns the methods string signature according to the ABI spec.
+//
+// Example
+//
+//     function foo(uint32 a, int b) = "foo(uint32,int256)"
+//
+// Please note that "int" is substitute for its canonical representation "int256"
+func (method Method) Sig() string {
+	types := make([]string, len(method.Inputs))
+	for i, input := range method.Inputs {
+		types[i] = input.Type.String()
+	}
+	return fmt.Sprintf("%v(%v)", method.RawName, strings.Join(types, ","))
+}
+
+func (method Method) String() string {
+	inputs := make([]string, len(method.Inputs))
+	for i, input := range method.Inputs {
+		inputs[i] = fmt.Sprintf("%v %v", input.Type, input.Name)
+	}
+	outputs := make([]string, len(method.Outputs))
+	for i, output := range method.Outputs {
+		outputs[i] = output.Type.String()
+		if len(output.Name) > 0 {
+			outputs[i] += fmt.Sprintf(" %v", output.Name)
+		}
+	}
+	constant := ""
+	if method.Const {
+		constant = "constant "
+	}
+	return fmt.Sprintf("function %v(%v) %sreturns(%v)", method.RawName, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", "))
+}
+
+// ID returns the canonical representation of the method's signature used by the
+// abi definition to identify method names and types.
+func (method Method) ID() []byte {
+	return crypto.Keccak256([]byte(method.Sig()))[:4]
+}