feat(target_chains/ethereum): add tx fee to evm contract

[cctdaniel]

Summary

Added support for transaction-level fees in Pyth price feed updates by:

• Introducing a new governance action SetTransactionFee (action type 8)
• Adding transaction fee state management in the Pyth contract
• Modifying fee calculation to include both per-update and per-transaction fees

Rationale

These changes enable charging a base transaction fee in addition to per-update fees for price feed updates. This helps:

• Better align fee structure with actual gas costs by having a fixed component per transaction
• Provide more flexible fee management through governance controls
• Create a more sustainable economic model for price feed updates

Technical Changes

1. Contract Changes:

   • Added transactionFeeInWei state variable to PythStorage
   • Modified getTotalFee() to include transaction fee component
   • Added getter/setter functions for transaction fee management
   • Implemented governance action handler for SetTransactionFee

2. Governance Support:

   • Added new SetTransactionFee action type and payload structure
   • Implemented payload parsing and validation
   • Added event emission for fee changes
   • Extended governance instruction set with transaction fee management

3. TypeScript Changes:

   • Added SetTransactionFee governance action implementation
   • Updated action type enums and decoders
   • Added buffer layout for fee value and exponent encoding

How has this been tested?

• Current tests cover my changes

  • Existing fee calculation tests continue to pass
  • Governance action handling tests remain valid

• Added new tests

  • Unit tests for transaction fee parsing and validation
  • Integration tests for fee calculation with transaction component
  • Governance action tests for SetTransactionFee

• Manually tested the code

  • Verified fee calculations with various update counts
  • Tested governance action execution flow
  • Validated event emission on fee changes

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

6 Skipped Deployments

Name	Status	Preview	Comments	Updated (UTC)
api-reference	⬜️ Ignored (Inspect)	Visit Preview		Mar 31, 2025 9:33am
component-library	⬜️ Ignored (Inspect)	Visit Preview		Mar 31, 2025 9:33am
entropy-debugger	⬜️ Ignored (Inspect)	Visit Preview		Mar 31, 2025 9:33am
insights	⬜️ Ignored (Inspect)	Visit Preview		Mar 31, 2025 9:33am
proposals	⬜️ Ignored (Inspect)	Visit Preview		Mar 31, 2025 9:33am
staking	⬜️ Ignored (Inspect)	Visit Preview		Mar 31, 2025 9:33am

[Copilot]

Pull Request Overview

This PR introduces transaction-level fee support for Ethereum contracts in the Pyth price feed updates through new governance actions and contract state changes.
Key changes include:

• Implementation of a new governance action "SetTransactionFee" with corresponding payload structure and encoding/decoding logic.
• Contract modifications to manage the transaction fee state and update fee calculations.
• Updates to governance payload tests to cover serialization and deserialization of the new action.

Reviewed Changes

Copilot reviewed 5 out of 11 changed files in this pull request and generated no comments.

File	Description
governance_payload/index.ts	Added import, case handling, and export for SetTransactionFee in the governance API.
governance_payload/SetTransactionFee.ts	Implemented the SetTransactionFee class with encode/decode functionality.
governance_payload/PythGovernanceAction.ts	Defined the new action type (value 8) for SetTransactionFee.
tests/GovernancePayload.test.ts	Added tests for serializing/deserializing the new SetTransactionFee action.

Files not reviewed (6)

• target_chains/ethereum/contracts/contracts/pyth/Pyth.sol: Language not supported
• target_chains/ethereum/contracts/contracts/pyth/PythGetters.sol: Language not supported
• target_chains/ethereum/contracts/contracts/pyth/PythGovernance.sol: Language not supported
• target_chains/ethereum/contracts/contracts/pyth/PythGovernanceInstructions.sol: Language not supported
• target_chains/ethereum/contracts/contracts/pyth/PythSetters.sol: Language not supported
• target_chains/ethereum/contracts/contracts/pyth/PythState.sol: Language not supported

Comments suppressed due to low confidence (1)

governance/xc_admin/packages/xc_admin_common/src/tests/GovernancePayload.test.ts:429

• [nitpick] Consider renaming record keys 'v' and 'e' to 'newFeeValue' and 'newFeeExpo' for improved clarity in the tests.

return fc.record({ v: fc.bigUintN(64), e: fc.bigUintN(64) })

[ali-bahjati]

Nice! and thanks for moving the tests to foundry. Please address my comments. Also can you update contract version so we don't miss it? (you can use a alpha next version because we are going to have more changes there)