[dannyshafer]

Summary

test() in @std/front-matter now takes formats?: readonly Format[] instead of Format[]. Instead of reassigning the parameter when it is omitted, it iterates over formats ?? EXTRACT_REGEXP_MAP.keys(), so behavior is unchanged.

Motivation

Part of #5831. test() never mutates formats, so callers holding a readonly array (for example ["yaml"] as const) currently get a type error for no reason. Other modules have already been updated the same way (#5832, #5735, #6639, #6911).

Test plan

• Added test() accepts readonly formats to front_matter/test_test.ts. It fails type-checking (TS2345) without the change and passes with it.
• deno test --doc front_matter/: 45 passed, 0 failed.
• deno fmt --check front_matter/ and deno lint front_matter/ are clean.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.04%. Comparing base (f834d02) to head (7f0c3ca).

Additional details and impacted files

@@           Coverage Diff            @@
##             main    #7364    +/-   ##
========================================
  Coverage   95.04%   95.04%            
========================================
  Files         619      619            
  Lines       52012    51760   -252     
  Branches     9450     9401    -49     
========================================
- Hits        49434    49195   -239     
+ Misses       2031     2022     -9     
+ Partials      547      543     -4     

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