Add fetchCloneArgs variants that read a slice of the immutable args

[Amxx]

Adds two overloads of Clones.fetchCloneArgs that read only part of the immutable args attached to a clone, avoiding allocation/copy of the full array when only a portion is needed:

• fetchCloneArgs(address instance, uint256 start) — copies from start (included) to the end.
• fetchCloneArgs(address instance, uint256 start, uint256 length) — copies at most length bytes starting at start.

Out-of-range arguments are truncated to the length of the immutable args (the returned array may be shorter than requested, or empty), matching the capping semantics of Bytes.slice/Bytes.splice rather than reverting. The existing fetchCloneArgs(address) is refactored to delegate to the new slicing overload, so all three share a single implementation.

PR Checklist

• Tests (Hardhat + Foundry fuzz, covering in-range and truncated reads)
• Documentation (NatSpec)
• Changeset entry

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🦋 Changeset detected

Latest commit: d45215b

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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[Copilot]

Pull request overview

This PR extends the Clones library with two new fetchCloneArgs overloads that return a slice of the immutable args appended to a clone’s runtime code, allowing callers to avoid allocating/copying the full args when only a subset is needed.

Changes:

• Added Clones.fetchCloneArgs(address,uint256) (slice from start to end) and Clones.fetchCloneArgs(address,uint256,uint256) (slice of at most length bytes from start), with truncation semantics instead of reverting on out-of-range.
• Refactored the existing fetchCloneArgs(address) implementation to delegate to the new slicing overload for a single shared implementation.
• Added Hardhat + Foundry coverage for in-range slicing and truncation behavior, and introduced a changeset entry for the new API.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
contracts/proxy/Clones.sol	Adds the two slicing overloads and refactors the original fetchCloneArgs(address) to reuse the shared slicing implementation.
test/proxy/Clones.test.js	Updates overload invocation syntax and adds tests covering slice reads, “slice to end”, and truncation behavior.
test/proxy/Clones.t.sol	Adds fuzz tests validating truncation semantics for both new overloads.
.changeset/clones-fetch-slice.md	Documents the new overloads as a minor change in the release notes.

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[coderabbitai]

Walkthrough

Clones.fetchCloneArgs now provides full, bounded, and start-to-end immutable-argument retrieval. Slice offsets and lengths are constrained to the available argument bytes before copying. Solidity and JavaScript tests cover normal slices, truncation, out-of-range starts, and overloaded calls. A minor Changesets entry documents the new variants.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: new fetchCloneArgs variants for slicing immutable args.
Description check	✅ Passed	The description directly matches the changeset by explaining the new overloads, truncation semantics, tests, and docs.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[coderabbitai]

Actionable comments posted: 1

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Verify each finding against current code. Fix only still-valid issues, skip the
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Inline comments:
In `@test/proxy/Clones.t.sol`:
- Around line 88-90: Update both fuzz-test assumptions surrounding
Clones.cloneDeterministicWithImmutableArgs to bound args.length by the
deployable 0x5fd3 maximum instead of 0xbfd3, ensuring generated inputs cannot
cause deployment to revert before the slice assertions.

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📥 Commits

Reviewing files that changed from the base of the PR and between b4f9524 and f920335.

📒 Files selected for processing (4)

• .changeset/clones-fetch-slice.md
• contracts/proxy/Clones.sol
• test/proxy/Clones.t.sol
• test/proxy/Clones.test.js

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (2)

test/proxy/Clones.t.sol:88

• The clone helpers revert with CloneArgumentsTooLong() when args.length > 0x5fd3 (see Clones._cloneCodeWithImmutableArgs). Using 0xbfd3 here doesn't exclude those reverting cases and can make the fuzz test fragile if Foundry’s generated bytes lengths increase in the future. Consider constraining the assume to the actual maximum supported args length.

        vm.assume(args.length < 0xbfd3);

test/proxy/Clones.t.sol:104

• Same as above: Clones reverts for args.length > 0x5fd3, so the fuzz precondition should cap to that limit to avoid generating reverting deployments.

        vm.assume(args.length < 0xbfd3);