feat(evm/sdk/js): add pyth filler

[ali-behjati]

Summary

This change revamps the deprecated EVM SDK to add a utilty for EVM to fill a call with the Pyth data it needs automatically. Under the hood it performs trace calls to detect Pyth contract usage and extracts the IDs from there, then fetches the update data from Hermes and creates a pyth update call.

This change is the alpha version and is subject to change. In the subsequent PRs more improvements will come. Also I'm going to improve the packaging (like dual export, file structure) later.

Please review the change commit-by-commit (the first commit has just removals, and the second one has actual changes).

Rationale

This change makes integrations to Pyth in the pull model easier.

How has this been tested?

• Manually tested the code. Tested two different methods in locally forked network (off eth mainnet) and OP Sepolia.

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[Copilot]

Pull Request Overview

This PR revamps the deprecated EVM SDK to automatically detect and bundle Pyth price update calls into EVM transactions.

• Added two tracer utilities (trace-call-many and debug-trace-call) to extract Pyth price feed IDs from RPC traces.
• Implemented fillPythUpdate in filler.ts to iteratively trace, fetch data from Hermes, compute fees, and produce bundled calls.
• Updated exports (index.ts) and documentation (README.md), removed old examples, and bumped package to 2.0.0-alpha.

Reviewed Changes

Copilot reviewed 14 out of 15 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/tracer/trace-call-many.ts	New batch tracer using trace_callMany to pull Pyth feed IDs
src/tracer/debug-trace-call.ts	Recursive tracer using debug_traceCall to extract nested feed IDs
src/filler.ts	Core fillPythUpdate implementation orchestrating trace + Hermes
src/multicall3-bundler.ts	Bundler combining Pyth update and original call via Multicall3
src/index.ts	Simplified exports exposing only new utilities
README.md	Updated quickstart and examples for fillPythUpdate utility

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

Comments suppressed due to low confidence (3)

target_chains/ethereum/sdk/js/README.md:25

• Documentation says fillPythUpdate uses trace_callMany by default, but in code defaultConfig.method is set to debug_traceCall. Align the docs with the actual default or update the default behavior in code.

This function uses the `trace_callMany` method by default but can be used with `debug_traceCall` and a bundler as well. See the example below for more information.

target_chains/ethereum/sdk/js/README.md:49

• In the example code, a comma is missing after the method: "trace_callMany" property, which makes the snippet invalid JavaScript.

            method: "trace_callMany"

target_chains/ethereum/sdk/js/src/filler.ts:135

• [nitpick] Consider adding unit tests for fillPythUpdate (and the tracer helpers) to verify that price feed extraction and iterative update bundling behave correctly under different scenarios.

export async function fillPythUpdate<

[aditya520]

Why do we need to iterate multiple times to find price feeds?

[ali-behjati]

    function increment() public returns (int256) {
        // Fetch the latest price from Pyth
        PythStructs.Price memory ethPrice = pyth.getPriceNoOlderThan(0xff61491a931112ddf1bd8147cd1b641375f79f5825126d665480874634fd0ace, 30);
        PythStructs.Price memory btcPrice = pyth.getPriceNoOlderThan(0xe62df6c8b4a85fe1a67db44dc12de5db330f7ac66b72dc658afedf0f4a415b43, 30);
    }

Consider a call to the function above is given to the method. The problem is that with the first trace call, the execution reverts at the first price fetch request and we only identify ETH price feed id. We need to iterate again, by bundling the update and call to pass that line to get the BTC price feed id.

[cprussin]

Looks good, mostly minor nits / suggestions, also the improvements to fillPythUpdate we'd discussed on slack

[cprussin]

minor nit but a better way to write the default is:

export async function fillPythUpdate(
  // ... other args
  config: Config = {
    method: "debug_traceCall",
    bundler: multicall3Bundler,
    maxIter: 5
  }
)

[ali-behjati]

I did it in the beginning but the linter told me not to do it.

[ali-behjati]

143:3 error Do not use an object literal as default for parameter config unicorn/no-object-as-default-parameter

i ignored it though.

[cprussin]

ah I actually was not aware of this rule, TIL

[cprussin]

As we'd discussed, barrel exports aren't great, I would consider just putting these into the same file -- I know it feels nice to have smaller separated files, but it does add fs read cost at load time for apps that use it. It's not a huge thing, but it adds up across the whole js package ecosystem, so the more packages that stop using barrel exports, the better.