Add the EVM.encodeABIWithSignature and EVM.decodeABIWithSignature fun…

…ctions

These functions can be used to ABI encode/decode function calls,
along with their arguments.

fvm/evm/stdlib/contract.cdc

@@ -157,4 +157,36 @@ contract EVM {
     fun decodeABI(types: [Type], data: [UInt8]): [AnyStruct] {
         return InternalEVM.decodeABI(types: types, data: data)
     }
+
+    access(all)
+    fun encodeABIWithSignature(
+        _ signature: String,
+        _ values: [AnyStruct]
+    ): [UInt8] {
+        let methodID = HashAlgorithm.KECCAK_256.hash(
+            signature.utf8
+        ).slice(from: 0, upTo: 4)
+        let arguments = InternalEVM.encodeABI(values)
+
+        return methodID.concat(arguments)
+    }
+
+    access(all)
+    fun decodeABIWithSignature(
+        _ signature: String,
+        types: [Type],
+        data: [UInt8]
+    ): [AnyStruct] {
+        let methodID = HashAlgorithm.KECCAK_256.hash(
+            signature.utf8
+        ).slice(from: 0, upTo: 4)
+
+        for byte in methodID {
+            if byte != data.removeFirst() {
+                panic("signature mismatch")
+            }
+        }
+
+        return InternalEVM.decodeABI(types: types, data: data)
+    }
 }