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Fix: decode dynamic indexed event topics as hex-encoded hash #250

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Merged
alisinabh merged 1 commit into from
Apr 14, 2026
Merged

Fix: decode dynamic indexed event topics as hex-encoded hash #250

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20 changes: 11 additions & 9 deletions lib/ethers/event.ex
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Original file line number Diff line number Diff line change
Expand Up @@ -65,15 +65,7 @@ defmodule Ethers.Event do
sub_topics_raw
|> Enum.map(&Utils.hex_decode!/1)
|> Enum.zip(ContractHelpers.event_indexed_types(selector))
|> Enum.map(fn
{data, :string} ->
{Utils.hex_encode(data), :string}

{data, type} ->
[decoded] = TypeDecoder.decode_raw(data, [type])
{decoded, type}
end)
|> Enum.map(fn {data, type} -> Utils.human_arg(data, type) end)
|> Enum.map(fn {raw, type} -> decode_sub_topic(raw, type) end)

topics = [FunctionSelector.encode(selector) | decoded_topics]

Expand Down Expand Up @@ -120,4 +112,14 @@ defmodule Ethers.Event do
{:ok, decode(log, selector)}
end
end

defp decode_sub_topic(raw, type) when type in [:string, :bytes], do: Utils.hex_encode(raw)
defp decode_sub_topic(raw, {:array, _}), do: Utils.hex_encode(raw)
defp decode_sub_topic(raw, {:array, _, _}), do: Utils.hex_encode(raw)
defp decode_sub_topic(raw, {:tuple, _}), do: Utils.hex_encode(raw)

defp decode_sub_topic(raw, type) do
[decoded] = TypeDecoder.decode_raw(raw, [type])
Utils.human_arg(decoded, type)
end
end
205 changes: 205 additions & 0 deletions test/ethers/event_test.exs
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Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,211 @@ defmodule Ethers.EventTest do
doctest Event

describe "decode/2" do
test "indexed bytes topic is returned as a hex-encoded keccak hash" do
selector = %ABI.FunctionSelector{
function: "SetLiquidityAdapterAndData",
method_id:
<<0x9D, 0xEB, 0x43, 0xD7, 0x14, 0x22, 0xAF, 0x41, 0x85, 0x3C, 0x39, 0x21, 0xFB, 0x36,
0x4B, 0x76, 0x47, 0xF9, 0xA9, 0xB1, 0x36, 0xE4, 0x6D, 0x66, 0xD4, 0x5C, 0x1B, 0xF7,
0x07, 0xAF, 0x70, 0x6C>>,
type: :event,
inputs_indexed: [true, true, true],
state_mutability: nil,
input_names: ["sender", "newLiquidityAdapter", "newLiquidityData"],
types: [:address, :address, :bytes],
returns: []
}

assert %Ethers.Event{
topics: [
_method,
"0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266",
"0x607Bca5681cEe20C82cF1D899E60B9eD36bc611C",
"0x64d65c9a2d91c36d56fbc42d69e979335320169b3df63bf92789e2c8883fcc64"
]
} =
Event.decode(
%{
"address" => "0xaa107ccfe230a29c345fd97bc6eb9bd2fccd0750",
"blockHash" =>
"0xe8885761ec559c5e267c48f44b4b12e4169f7d3a116f5e8f43314147722f0d83",
"blockNumber" => "0x1138b39",
"data" => "0x",
"logIndex" => "0x1a1",
"removed" => false,
"topics" => [
"0x9deb43d71422af41853c3921fb364b7647f9a9b136e46d66d45c1bf707af706c",
"0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266",
"0x000000000000000000000000607bca5681cee20c82cf1d899e60b9ed36bc611c",
"0x64d65c9a2d91c36d56fbc42d69e979335320169b3df63bf92789e2c8883fcc64"
],
"transactionHash" =>
"0xf6e06e4f3fbd67088e8278843e55862957537760c63bae7b682a0e39da75b45d",
"transactionIndex" => "0x83"
},
selector
)
end

test "indexed string topic is returned as a hex-encoded keccak hash" do
selector = %ABI.FunctionSelector{
function: "E",
method_id: :binary.copy(<<0>>, 32),
type: :event,
inputs_indexed: [true],
state_mutability: nil,
input_names: ["name"],
types: [:string],
returns: []
}

assert %Ethers.Event{
topics: [
_method,
"0x64d65c9a2d91c36d56fbc42d69e979335320169b3df63bf92789e2c8883fcc64"
]
} =
Event.decode(
%{
"address" => "0xaa107ccfe230a29c345fd97bc6eb9bd2fccd0750",
"blockHash" =>
"0xe8885761ec559c5e267c48f44b4b12e4169f7d3a116f5e8f43314147722f0d83",
"blockNumber" => "0x1138b39",
"data" => "0x",
"logIndex" => "0x1a1",
"removed" => false,
"topics" => [
"0x0000000000000000000000000000000000000000000000000000000000000000",
"0x64d65c9a2d91c36d56fbc42d69e979335320169b3df63bf92789e2c8883fcc64"
],
"transactionHash" =>
"0xf6e06e4f3fbd67088e8278843e55862957537760c63bae7b682a0e39da75b45d",
"transactionIndex" => "0x83"
},
selector
)
end

test "indexed dynamic array topic is returned as a hex-encoded keccak hash" do
selector = %ABI.FunctionSelector{
function: "E",
method_id: :binary.copy(<<0>>, 32),
type: :event,
inputs_indexed: [true],
state_mutability: nil,
input_names: ["xs"],
types: [{:array, {:uint, 256}}],
returns: []
}

assert %Ethers.Event{
topics: [
_method,
"0xabcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789"
]
} =
Event.decode(
%{
"address" => "0xaa107ccfe230a29c345fd97bc6eb9bd2fccd0750",
"blockHash" =>
"0xe8885761ec559c5e267c48f44b4b12e4169f7d3a116f5e8f43314147722f0d83",
"blockNumber" => "0x1138b39",
"data" => "0x",
"logIndex" => "0x1a1",
"removed" => false,
"topics" => [
"0x0000000000000000000000000000000000000000000000000000000000000000",
"0xabcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789"
],
"transactionHash" =>
"0xf6e06e4f3fbd67088e8278843e55862957537760c63bae7b682a0e39da75b45d",
"transactionIndex" => "0x83"
},
selector
)
end

test "indexed tuple topic is returned as a hex-encoded keccak hash" do
selector = %ABI.FunctionSelector{
function: "E",
method_id: :binary.copy(<<0>>, 32),
type: :event,
inputs_indexed: [true],
state_mutability: nil,
input_names: ["s"],
types: [{:tuple, [{:uint, 256}, :address]}],
returns: []
}

assert %Ethers.Event{
topics: [
_method,
"0x1111111111111111111111111111111111111111111111111111111111111111"
]
} =
Event.decode(
%{
"address" => "0xaa107ccfe230a29c345fd97bc6eb9bd2fccd0750",
"blockHash" =>
"0xe8885761ec559c5e267c48f44b4b12e4169f7d3a116f5e8f43314147722f0d83",
"blockNumber" => "0x1138b39",
"data" => "0x",
"logIndex" => "0x1a1",
"removed" => false,
"topics" => [
"0x0000000000000000000000000000000000000000000000000000000000000000",
"0x1111111111111111111111111111111111111111111111111111111111111111"
],
"transactionHash" =>
"0xf6e06e4f3fbd67088e8278843e55862957537760c63bae7b682a0e39da75b45d",
"transactionIndex" => "0x83"
},
selector
)
end

test "mixed indexed bytes and non-indexed uint256 decodes both" do
selector = %ABI.FunctionSelector{
function: "E",
method_id: :binary.copy(<<0>>, 32),
type: :event,
inputs_indexed: [true, true, false],
state_mutability: nil,
input_names: ["a", "b", "nonIndexed"],
types: [:address, :bytes, {:uint, 256}],
returns: [uint: 256]
}

assert %Ethers.Event{
data: [42],
topics: [
_method,
"0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266",
"0x64d65c9a2d91c36d56fbc42d69e979335320169b3df63bf92789e2c8883fcc64"
]
} =
Event.decode(
%{
"address" => "0xaa107ccfe230a29c345fd97bc6eb9bd2fccd0750",
"blockHash" =>
"0xe8885761ec559c5e267c48f44b4b12e4169f7d3a116f5e8f43314147722f0d83",
"blockNumber" => "0x1138b39",
"data" => "0x000000000000000000000000000000000000000000000000000000000000002a",
"logIndex" => "0x1a1",
"removed" => false,
"topics" => [
"0x0000000000000000000000000000000000000000000000000000000000000000",
"0x000000000000000000000000f39fd6e51aad88f6f4ce6ab8827279cfffb92266",
"0x64d65c9a2d91c36d56fbc42d69e979335320169b3df63bf92789e2c8883fcc64"
],
"transactionHash" =>
"0xf6e06e4f3fbd67088e8278843e55862957537760c63bae7b682a0e39da75b45d",
"transactionIndex" => "0x83"
},
selector
)
end

test "decode log with no data returns empty list" do
selector = %ABI.FunctionSelector{
function: "Approval",
Expand Down
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