Added support for EIP-7702 transactions following the approach used b…

…y 1559.

lib/eth/tx.rb

@@ -17,6 +17,7 @@
 require "eth/chain"
 require "eth/tx/eip1559"
 require "eth/tx/eip2930"
+require "eth/tx/eip7702"
 require "eth/tx/legacy"
 require "eth/unit"
 
@@ -72,6 +73,9 @@ class ParameterError < TypeError; end
     # The EIP-1559 transaction type is 2.
     TYPE_1559 = 0x02.freeze
 
+    # The EIP-7702 transaction type is 4.
+    TYPE_7702 = 0x04.freeze
+
     # The zero byte is 0x00.
     ZERO_BYTE = "\x00".freeze
 
@@ -80,6 +84,8 @@ class ParameterError < TypeError; end
 
     # Creates a new transaction of any type for given parameters and chain ID.
     # Required parameters are (optional in brackets):
+    # - EIP-7702: chain_id, nonce, priority_fee, max_gas_fee, gas_limit, authorizations(, from, to,
+    #   value, data, access_list)
     # - EIP-1559: chain_id, nonce, priority_fee, max_gas_fee, gas_limit(, from, to,
     #   value, data, access_list)
     # - EIP-2930: chain_id, nonce, gas_price, gas_limit, access_list(, from, to,
@@ -90,6 +96,12 @@ class ParameterError < TypeError; end
     # @param chain_id [Integer] the EIP-155 Chain ID (legacy transactions only).
     def new(params, chain_id = Chain::ETHEREUM)
 
+      # if we deal with authorizations, attempt EIP-7702
+      unless params[:authorization_list].nil?
+        params[:chain_id] = chain_id if params[:chain_id].nil?
+        return Tx::Eip7702.new params
+      end
+
       # if we deal with max gas fee parameter, attempt EIP-1559
       unless params[:max_gas_fee].nil?
         params[:chain_id] = chain_id if params[:chain_id].nil?
@@ -114,8 +126,14 @@ def new(params, chain_id = Chain::ETHEREUM)
     # @raise [TransactionTypeError] if the transaction type is unknown.
     def decode(hex)
       hex = Util.remove_hex_prefix hex
+      puts hex[0, 2].to_i(16)
       type = hex[0, 2].to_i(16)
+
       case type
+      when TYPE_7702
+
+        # EIP-1559 transaction (type 2)
+        return Tx::Eip7702.decode hex
       when TYPE_1559
 
         # EIP-1559 transaction (type 2)
@@ -142,6 +160,8 @@ def decode(hex)
     # @raise [TransactionTypeError] if the transaction type is unknown.
     def unsigned_copy(tx)
       case tx.type
+      when TYPE_7702
+        return Tx::Eip7702.unsigned_copy tx
       when TYPE_1559
 
         # EIP-1559 transaction (type 2)