Add EIP-2930 support (#179)

* Dynamically generate t_payload typespec

* Add EIP-2930 support

* Fix typedoc

* Improve tests

* Update CHANGELOG

Author: alisinabh

CHANGELOG.md

@@ -6,6 +6,7 @@
 
 - Support [EIP-1191](https://eips.ethereum.org/EIPS/eip-1191): Add chain id to mixed-case checksum address encoding
 - Add [EIP-4844](https://eips.ethereum.org/EIPS/eip-4844) transaction support
+- Add [EIP-2930](https://eips.ethereum.org/EIPS/eip-2930) transaction support
 
 ## v0.6.1 (2025-01-02)
 

lib/ethers/transaction.ex

@@ -9,12 +9,33 @@ defmodule Ethers.Transaction do
   """
 
   alias Ethers.Transaction.Eip1559
+  alias Ethers.Transaction.Eip2930
   alias Ethers.Transaction.Eip4844
   alias Ethers.Transaction.Legacy
   alias Ethers.Transaction.Protocol, as: TxProtocol
   alias Ethers.Transaction.Signed
   alias Ethers.Utils
 
+  @default_transaction_types [Eip1559, Eip2930, Eip4844, Legacy]
+
+  @transaction_types Application.compile_env(
+                       :ethers,
+                       :transaction_types,
+                       @default_transaction_types
+                     )
+
+  @default_transaction_type Eip1559
+
+  @rpc_fields %{
+    access_list: :accessList,
+    blob_versioned_hashes: :blobVersionedHashes,
+    chain_id: :chainId,
+    gas_price: :gasPrice,
+    max_fee_per_blob_gas: :maxFeePerBlobGas,
+    max_fee_per_gas: :maxFeePerGas,
+    max_priority_fee_per_gas: :maxPriorityFeePerGas
+  }
+
   @typedoc """
   EVM Transaction type
   """
@@ -23,7 +44,12 @@ defmodule Ethers.Transaction do
   @typedoc """
   EVM Transaction payload type
   """
-  @type t_payload :: Eip4844.t() | Eip1559.t() | Legacy.t()
+  @type t_payload ::
+          unquote(
+            @transaction_types
+            |> Enum.map(&{{:., [], [{:__aliases__, [alias: false], [&1]}, :t]}, [], []})
+            |> Enum.reduce(&{:|, [], [&1, &2]})
+          )
 
   @doc "Creates a new transaction struct with the given parameters."
   @callback new(map()) :: {:ok, t()} | {:error, reason :: atom()}
@@ -41,24 +67,6 @@ defmodule Ethers.Transaction do
   @callback from_rlp_list([binary() | [binary()]]) ::
               {:ok, t(), rest :: [binary() | [binary()]]} | {:error, reason :: term()}
 
-  @default_transaction_type Eip1559
-
-  @transaction_type_modules Application.compile_env(:ethers, :transaction_types, [
-                              Eip4844,
-                              Eip1559,
-                              Legacy
-                            ])
-
-  @rpc_fields %{
-    access_list: :accessList,
-    blob_versioned_hashes: :blobVersionedHashes,
-    chain_id: :chainId,
-    gas_price: :gasPrice,
-    max_fee_per_blob_gas: :maxFeePerBlobGas,
-    max_fee_per_gas: :maxFeePerGas,
-    max_priority_fee_per_gas: :maxPriorityFeePerGas
-  }
-
   @doc """
   Creates a new transaction struct with the given parameters.
 
@@ -72,7 +80,7 @@ defmodule Ethers.Transaction do
   @spec new(map()) :: {:ok, t()} | {:error, reason :: term()}
   def new(params) do
     case Map.fetch(params, :type) do
-      {:ok, type} when type in @transaction_type_modules ->
+      {:ok, type} when type in @transaction_types ->
         input =
           params
           |> Map.get(:input, Map.get(params, :data))
@@ -190,7 +198,7 @@ defmodule Ethers.Transaction do
     end
   end
 
-  Enum.each(@transaction_type_modules, fn module ->
+  Enum.each(@transaction_types, fn module ->
     type_envelope = module.type_envelope()
 
     defp decode_transaction_data(<<unquote(type_envelope)::binary, rest::binary>>) do
@@ -375,7 +383,7 @@ defmodule Ethers.Transaction do
 
   defp decode_type("0x" <> _ = type), do: decode_type(Utils.hex_decode!(type))
 
-  Enum.each(@transaction_type_modules, fn module ->
+  Enum.each(@transaction_types, fn module ->
     type_envelope = module.type_envelope()
     defp decode_type(unquote(type_envelope)), do: {:ok, unquote(module)}
   end)

lib/ethers/transaction/eip2930.ex

@@ -0,0 +1,126 @@
+defmodule Ethers.Transaction.Eip2930 do
+  @moduledoc """
+  Transaction struct and protocol implementation for Ethereum Improvement Proposal (EIP) 2930
+  transactions. EIP-2930 introduced a new transaction type that includes an access list,
+  allowing transactions to pre-specify and pre-pay for account and storage access to mitigate
+  gas cost changes from EIP-2929 and prevent contract breakage. The access list format also
+  enables future use cases like block-wide witnesses and static state access patterns.
+
+  See: https://eips.ethereum.org/EIPS/eip-2930
+  """
+
+  alias Ethers.Types
+  alias Ethers.Utils
+
+  @behaviour Ethers.Transaction
+
+  @type_id 1
+
+  @enforce_keys [:chain_id, :nonce, :gas_price, :gas]
+  defstruct [
+    :chain_id,
+    :nonce,
+    :gas_price,
+    :gas,
+    :to,
+    :value,
+    :input,
+    access_list: []
+  ]
+
+  @typedoc """
+  A transaction type following EIP-2930 (Type-1) and incorporating the following fields:
+  - `chain_id` - chain ID of network where the transaction is to be executed
+  - `nonce` - sequence number for the transaction from this sender
+  - `gas_price`: Price willing to pay for each unit of gas (in wei)
+  - `gas` - maximum amount of gas allowed for transaction execution
+  - `to` - destination address for transaction, nil for contract creation
+  - `value` - amount of ether (in wei) to transfer
+  - `input` - data payload of the transaction
+  - `access_list` - list of addresses and storage keys to warm up (introduced in EIP-2930)
+  """
+  @type t :: %__MODULE__{
+          chain_id: non_neg_integer(),
+          nonce: non_neg_integer(),
+          gas_price: non_neg_integer(),
+          gas: non_neg_integer(),
+          to: Types.t_address() | nil,
+          value: non_neg_integer(),
+          input: binary(),
+          access_list: [{binary(), [binary()]}]
+        }
+
+  @impl Ethers.Transaction
+  def new(params) do
+    to = params[:to]
+
+    {:ok,
+     %__MODULE__{
+       chain_id: params.chain_id,
+       nonce: params.nonce,
+       gas_price: params.gas_price,
+       gas: params.gas,
+       to: to && Utils.to_checksum_address(to),
+       value: params[:value] || 0,
+       input: params[:input] || params[:data] || "",
+       access_list: params[:access_list] || []
+     }}
+  end
+
+  @impl Ethers.Transaction
+  def auto_fetchable_fields do
+    [:chain_id, :nonce, :gas_price, :gas]
+  end
+
+  @impl Ethers.Transaction
+  def type_envelope, do: <<type_id()>>
+
+  @impl Ethers.Transaction
+  def type_id, do: @type_id
+
+  @impl Ethers.Transaction
+  def from_rlp_list([
+        chain_id,
+        nonce,
+        gas_price,
+        gas,
+        to,
+        value,
+        input,
+        access_list | rest
+      ]) do
+    {:ok,
+     %__MODULE__{
+       chain_id: :binary.decode_unsigned(chain_id),
+       nonce: :binary.decode_unsigned(nonce),
+       gas_price: :binary.decode_unsigned(gas_price),
+       gas: :binary.decode_unsigned(gas),
+       to: (to != "" && Utils.encode_address!(to)) || nil,
+       value: :binary.decode_unsigned(value),
+       input: input,
+       access_list: access_list
+     }, rest}
+  end
+
+  def from_rlp_list(_rlp_list), do: {:error, :transaction_decode_failed}
+
+  defimpl Ethers.Transaction.Protocol do
+    def type_id(_transaction), do: @for.type_id()
+
+    def type_envelope(_transaction), do: @for.type_envelope()
+
+    def to_rlp_list(tx, _mode) do
+      # Eip2930 does not discriminate in RLP encoding between payload and hash
+      [
+        tx.chain_id,
+        tx.nonce,
+        tx.gas_price,
+        tx.gas,
+        (tx.to && Utils.decode_address!(tx.to)) || "",
+        tx.value,
+        tx.input,
+        tx.access_list || []
+      ]
+    end
+  end
+end

test/ethers/transaction_test.exs

@@ -62,7 +62,7 @@ defmodule Ethers.TransactionTest do
   end
 
   describe "decode/1" do
-    test "decodes raw EIP-4844 transaction correctly" do
+    test "decodes raw EIP-4844 transaction and re-encodes it correctly" do
       raw_tx =
         "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"
 
@@ -145,9 +145,11 @@ defmodule Ethers.TransactionTest do
                "0x0169766b1aff3508331a39e7081e591a3ff3bacf957788571269797db7ff3ccc",
                "0x017045639ffe91febe66cc4427fcf6331980dd9a0dab4af3e81c5514b918ed61"
              ]
+
+      assert Ethers.Utils.hex_encode(Transaction.encode(decoded_tx)) == raw_tx
     end
 
-    test "decodes raw EIP-1559 transaction correctly" do
+    test "decodes raw EIP-1559 transaction and re-encodes it correctly" do
       raw_tx =
         "0x02f8af0177837a12008502c4bfbc3282f88c948881562783028f5c1bcb985d2283d5e170d8888880b844a9059cbb0000000000000000000000002ef7f5c7c727d8845e685f462a5b4f8ac4972a6700000000000000000000000000000000000000000000051ab2ea6fbbb7420000c001a007280557e86f690290f9ea9e26cc17e0cf09a17f6c2d041e95b33be4b81888d0a06c7a24e8fba5cceb455b19950849b9733f0deb92d7e8c2a919f4a82df9c6036a"
 
@@ -172,9 +174,40 @@ defmodule Ethers.TransactionTest do
       assert decoded_tx.payload.max_priority_fee_per_gas == 8_000_000
       assert decoded_tx.payload.to == "0x8881562783028F5c1BCB985d2283D5E170D88888"
       assert decoded_tx.payload.value == 0
+
+      assert Ethers.Utils.hex_encode(Transaction.encode(decoded_tx)) == raw_tx
     end
 
-    test "decodes raw legacy transaction correctly" do
+    test "decodes raw EIP-2930 transaction and re-encodes it correctly" do
+      raw_tx =
+        "0x01f903640182dd688503a656ac80830623c4944a137fd5e7a256ef08a7de531a17d0be0cc7b6b680b901a46dbf2fa0000000000000000000000000e592427a0aece92de3edee1f18e0157c05861564000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000104414bf3890000000000000000000000007d1afa7b718fb893db30a3abc0cfc608aacfebb0000000000000000000000000a0b86991c6218b36c1d19d4a2e9eb0ce3606eb480000000000000000000000000000000000000000000000000000000000000bb80000000000000000000000004a137fd5e7a256ef08a7de531a17d0be0cc7b6b60000000000000000000000000000000000000000000000000000000060bda78e0000000000000000000000000000000000000000000000cc223b921be6800000000000000000000000000000000000000000000000000000000000017dd4e6ca000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f90153f87a9407a6e955ba4345bae83ac2a6faa771fddd8a2011f863a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000001a00000000000000000000000000000000000000000000000000000000000000008f87a947d1afa7b718fb893db30a3abc0cfc608aacfebb0f863a014d5312942240e565c56aec11806ce58e3c0e38c96269d759c5d35a2a2e4a449a02701fd0b2638f33db225d91c6adbdad46590a86a09a2b2c386405c2f742af842a037b0b82ee5d8a88672df3895a46af48bbcd30d6efcc908136e29456fa30604bbf85994a0b86991c6218b36c1d19d4a2e9eb0ce3606eb48f842a037570cf18c6d95744a154fa2b19b7e958c78ef68b8c60a80dc527fc15e2ceb8fa06e89d31e3fd8d2bf0b411c458e98c7463bf723878c3ce8a845bcf9dc3b2e391780a01d40605de92c503219631e625ca0d023df8dfef9058896804fb1952d386b64e1a00e0ec0714b7956fe29820cb62998936b78ca4b8a3b05291db90e475244d5c63f"
+
+      expected_from = "0x005FdE5294199d5C3Eb5Eb7a6E51954123b74b1c"
+      expected_hash = "0xdb32a678b6c5855eb3c5ff47513e136a85a391469755d045d8846e37fc99d774"
+
+      assert {:ok, decoded_tx} = Transaction.decode(raw_tx)
+      assert %Transaction.Signed{payload: %Transaction.Eip2930{}} = decoded_tx
+
+      # Verify transaction hash matches
+      assert Transaction.transaction_hash(decoded_tx) == expected_hash
+
+      # Verify recovered from address
+      recovered_from = Transaction.Signed.from_address(decoded_tx)
+      assert String.downcase(recovered_from) == String.downcase(expected_from)
+
+      # Verify other transaction fields
+      assert decoded_tx.payload.chain_id == 1
+      assert decoded_tx.payload.gas == 402_372
+      assert decoded_tx.payload.gas_price == 15_675_600_000
+      assert decoded_tx.payload.nonce == 56_680
+      assert decoded_tx.payload.to == "0x4A137FD5e7a256eF08A7De531A17D0BE0cc7B6b6"
+      assert decoded_tx.payload.value == 0
+      assert Enum.count(decoded_tx.payload.access_list) == 3
+
+      assert Ethers.Utils.hex_encode(Transaction.encode(decoded_tx)) == raw_tx
+    end
+
+    test "decodes raw legacy transaction and re-encodes it correctly" do
       raw_tx =
         "0xf86c81c6850c92a69c0082520894e48c9a989438606a79a7560cfba3d34bafbac38e87596f744abf34368025a0ee0b54a64cf8130e36cd1d19395d6d434c285c832a7908873a24610ec32896dfa070b5e779cdcaf5c661c1df44e80895f6ab68463d3ede2cf4955855bc3c6edebb"
 
@@ -198,6 +231,8 @@ defmodule Ethers.TransactionTest do
       assert decoded_tx.payload.gas_price == 54_000_000_000
       assert decoded_tx.payload.to == "0xe48C9A989438606a79a7560cfba3d34BAfBAC38E"
       assert decoded_tx.payload.value == 25_173_818_188_182_582
+
+      assert Ethers.Utils.hex_encode(Transaction.encode(decoded_tx)) == raw_tx
     end
   end
 end