fix(once): Remove type assertion for better type safety

[wo-o29]

Summary

This PR improves the once function by removing the type assertion (as F) and using an explicit return type instead. This change enhances type safety while maintaining the same functionality.

Changes

• Removed as F type assertion from the return statement
• Changed return type from F to (...args: Parameters<F>) => ReturnType<F>
• Simplified the first function overload to match the implementation signature
• Improved type safety by letting TypeScript properly infer and validate the return type

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Project	Deployment	Preview	Comments	Updated (UTC)
es-toolkit	Ready	Preview	Comment	Oct 11, 2025 2:50pm

[Copilot]

Pull Request Overview

This PR enhances type safety in the once function by removing a type assertion and replacing it with an explicit return type. The change eliminates the unsafe as F cast while maintaining the same functionality through proper TypeScript type inference.

Key Changes

• Removed the as F type assertion from the return statement
• Changed the return type from F to (...args: Parameters<F>) => ReturnType<F>
• Reformatted the function signature for better readability

Comments suppressed due to low confidence (1)

src/function/once.ts:15

• The first overload signature should be updated to match the new implementation return type (...args: Parameters<F>) => ReturnType<F> for consistency.

export function once<F extends (...args: any[]) => any>(func: F): F;

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.90%. Comparing base (21bd853) to head (75f5f42).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1462   +/-   ##
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  Coverage   99.90%   99.90%           
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  Files         468      468           
  Lines        4439     4439           
  Branches     1309     1309           
=======================================
  Hits         4435     4435           
  Misses          4        4           

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