feat(precompiles): erc20 factory precompile

[GuillemGarciaDev]

Description

This PR implements event emission functionality for the ERC20 Factory precompile and fixes critical issues with event topic handling.

ERC20 Factory Precompile Overview

The ERC20 Factory precompile is a precompile deployed at address 0x0000000000000000000000000000000000000900 that enables deterministic creation of ERC20 token pairs. It provides a factory pattern for deploying ERC20 tokens with predictable addresses.

Core Functionality

The precompile bridges Ethereum-style ERC20 tokens with Cosmos SDK's bank module, automatically:

• Creating bank denomination metadata for new tokens
• Registering token pairs in the ERC20 module
• Enabling dynamic precompiles for token contracts

Available Methods

1. create(uint8 tokenPairType, bytes32 salt, string name, string symbol, uint8 decimals) → address

Transaction Method | Gas Cost: 3,000,000

Creates a new ERC20 token pair and returns the deployed contract address.

Parameters:

• tokenPairType: Type identifier for the token pair (uint8)
• salt: 32-byte salt for deterministic address generation
• name: Token name (3-128 characters)
• symbol: Token symbol (3-16 characters)
• decimals: Number of decimal places (uint8)

Process:

1. Calculates deterministic address using CREATE2
2. Creates bank denomination metadata
3. Registers token pair in ERC20 module
4. Enables dynamic precompiles for the token
5. Emits Create event
6. Returns the token contract address

2. calculateAddress(uint8 tokenPairType, bytes32 salt) → address

View Method | Gas Cost: 3,000

Calculates the deterministic address where a token would be deployed without actually creating it.

Parameters:

• tokenPairType: Type identifier for the token pair
• salt: 32-byte salt for address calculation

Returns: The calculated contract address using CREATE2 formula

Events Emitted

Create(address indexed tokenAddress, uint8 tokenPairType, bytes32 salt, string name, string symbol, uint8 decimals)

Emitted when a new ERC20 token pair is successfully created.

Indexed Parameters:

• tokenAddress: Address of the deployed token contract

Non-Indexed Parameters:

• tokenPairType: Type identifier used during creation
• salt: Salt value used for deterministic deployment
• name: Token name
• symbol: Token symbol
• decimals: Decimal precision

Integration with Cosmos SDK

The precompile seamlessly integrates with multiple Cosmos SDK modules:

• Bank Module: Creates denomination metadata for token accounting
• ERC20 Module: Registers token pairs for cross-module compatibility

Critical Files to Review

• precompiles/erc20factory/events.go - Core event emission logic
• precompiles/erc20factory/types.go - Event struct definitions
• precompiles/erc20factory/tx.go - Integration with Create method
• tests/integration/precompiles/erc20factory/test_events.go - Go test coverage
• tests/solidity/suites/precompiles/test/erc20factory.js - JavaScript test coverage

Closes: #XXXX

---

Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

I have...

• tackled an existing issue or discussed with a team member
• left instructions on how to review the changes
• targeted the main branch

Reviewers Checklist

All items are required.
Please add a note if the item is not applicable
and please add your handle next to the items reviewed
if you only reviewed selected items.

I have...

• added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• confirmed all author checklist items have been addressed
• confirmed that this PR does not change production code
• reviewed content
• tested instructions (if applicable)
• confirmed all CI checks have passed

[GuillemGarciaDev]

@aljo242 @vladjdk reopening this PR since it was closed by error. Ready for another review, all conflicts solved.

[aljo242]

Hey @GuillemGarciaDev looks like we have some solidity tests failing from these changes

[GuillemGarciaDev]

Hey @GuillemGarciaDev looks like we have some solidity tests failing from these changes

Fixes applied! They should pass now.

[vladjdk]

Overall, looks great! I do have a couple nits and comments, though. After you look at those, we should be good to finally merge :)

[GuillemGarciaDev]

@vladjdk All comments addressed!

[GuillemGarciaDev]

@aljo242 @vladjdk should I update the CHANGELOG?

[vladjdk]

@GuillemGarciaDev, yes, please add an entry into unreleased!

[GuillemGarciaDev]

@GuillemGarciaDev, yes, please add an entry into unreleased!

Done

[vladjdk]

LGTM! @GuillemGarciaDev feel free to merge after the conflict is resolved. Thank you again for your work!

[GuillemGarciaDev]

LGTM! @GuillemGarciaDev feel free to merge after the conflict is resolved. Thank you again for your work!

Thanks @vladjdk ! I do not have permissions though, already fixed the comments. A pleasure!