Add RLP and TrieProof libraries

[ernestognw]

Requires:

• https://github.com/OpenZeppelin/openzeppelin-contracts/pull/5189
• https://github.com/OpenZeppelin/openzeppelin-contracts/pull/5724
• https://github.com/OpenZeppelin/openzeppelin-contracts/pull/5725

PR Checklist

• [ ] Tests
• [ ] Documentation
• [ ] Changeset entry (run npx changeset add)

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 371595d3959a96a030060dd03ae74e6082d5aedd

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
openzeppelin-solidity	Minor

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[0xClandestine]

will gladly help on this

[ernestognw]

Hi @0xClandestine, so in there is an open discussion in #5189, some open issues in https://github.com/OpenZeppelin/openzeppelin-contracts/pull/5724 and https://github.com/OpenZeppelin/openzeppelin-contracts/pull/5725

I would appreciate help in advancing any of these PRs, as of now we're attending the 5.4 audit release and these are 5.5 candidates. For this particular PR, we're missing test, je 😅

[ernestognw]

This PR must be updated if any of #5792 or #5726 is merged. Essentially replacing these RLP private functions and string's equal

[coderabbitai[bot]]

Walkthrough

This change adds a new RLP Solidity library (encoding/decoding, item types, errors, encoder helpers). The Memory library gains a public Slice type and slice utilities with bounds checks. The Bytes library introduces a memory-only Accumulator with push/shift/flatten operations. Solidity pragma updates to ^0.8.24 appear in ERC4626.sol and Memory.sol. Stateless.sol imports RLP. README is updated to reference RLP. New tests cover Bytes.Accumulator, Memory.Slice, and comprehensive RLP encode/decode in Solidity and JavaScript. A changeset declares a minor version bump and mentions the new RLP library.

Suggested labels

ignore-changeset

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The title "Add RLP library" is concise and accurately reflects the primary change in the changeset — the addition of contracts/utils/RLP.sol and its accompanying tests and docs references — so it clearly summarizes the PR's main purpose for a reviewer scanning history.
Description Check	✅ Passed	The pull request description lists required dependent PRs, notes outstanding checklist items (tests, documentation, changeset), and provides contextual guidance, so it is directly related to the changeset and not off-topic.

✨ Finishing touches

• [ ] 📝 Generate Docstrings

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• [ ] Post copyable unit tests in a comment

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[Amxx]

We should decide weither we are ok with the following feature:

• Memory slices (in memory.sol ?)
• Bytes accumulator (in bytes.sol ? in a dedicated file under struct ?)
• RLP encoder interface (uses Bytes accumulator)

Overall, we should also discuss naming of the functions in RLP.sol.

[socket-security[bot]]

No dependency changes detected. Learn more about Socket for GitHub.

👍 No dependency changes detected in pull request

[ernestognw]

The only thing left to discuss is the error to use in _decodeLength. See https://github.com/OpenZeppelin/openzeppelin-contracts/pull/5680#discussion_r2356559020

Once that's done I think the PR should be good. The main problem may be the coverage hit but we may be fine with that (?)

[ernestognw]

Can't approve my own PR, but LGTM

[ernestognw]

The forward looks pretty cool, though!