fix: avoid quicksort stack overflow on worst-case inputs

[rajatbeladiya]

Reworks Arrays._quickSort to recurse on the smaller partition and iterate over the larger partition. This prevents deep recursion on worst-case inputs (e.g., already-sorted/reversed arrays) which can otherwise lead to EVM stack overflow.

Changes:

• Update generator template scripts/generate/templates/Arrays.js (Arrays.sol is generated).
• Add a regression test for uint256[] of length 256 (including sorted + reversed cases).

Tested:

• npm run test:generation
• npx hardhat test test/utils/Arrays.test.js --grep sort
• npm run lint:sol

Closes #6289.

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Latest commit: 36850f8

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📥 Commits

Reviewing files that changed from the base of the PR and between 95a983a and 36850f8.

📒 Files selected for processing (3)

• contracts/utils/Arrays.sol
• scripts/generate/templates/Arrays.js
• test/utils/Arrays.test.js

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Walkthrough

The pull request optimizes the _quickSort() function in the Arrays utility by replacing a two-way recursive quicksort with a hybrid iterative-recursive approach. The implementation wraps the sorting logic in a while loop that continues processing while partition size is at least 0x40. After each partition operation, the code recurses only on the smaller partition and updates the loop bounds to handle the larger partition iteratively. The corresponding template file and tests are updated accordingly, with test coverage expanded to include larger array sizes.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and accurately summarizes the main change: modifying quicksort to avoid stack overflow on worst-case inputs.
Description check	✅ Passed	The description is directly related to the changeset, explaining the rework of Arrays._quickSort and the addition of regression tests.
Linked Issues check	✅ Passed	The PR implements the primary solution from issue #6289: replacing dual recursion with recursion on smaller partition and iteration on larger partition to prevent stack overflow.
Out of Scope Changes check	✅ Passed	All changes are within scope: the template update, generated contract changes, and test additions directly address the stack overflow optimization objective from issue #6289.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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[Amxx]

Duplicate of #6324