build(deps-dev): bump js-yaml from 4.1.0 to 4.2.0

[dependabot]

Bumps js-yaml from 4.1.0 to 4.2.0.

Changelog

Sourced from js-yaml's changelog.

[4.2.0] - 2026-06-01

Added

• Added docs/safety.md with notes about processing untrusted YAML.
• Added maxDepth (100) loader option. Not a problem, but gives a better exception instead of RangeError on stack overflow.
• Added maxMergeSeqLength (20) loader option. Not a problem after merge fix, but an additional restriction for safety.
• Added sourcemaps to dist/ builds.

Changed

• Stop resolving numbers with underscores as numeric scalars, #627.
• Switched dev toolchains to Vite / neostandard.
• Updated demo.
• Reorganized tests.
• dist/ files are no longer kept in the repository.

Fixed

• Fix parsing of properties on the first implicit block mapping key, #62.
• Fix trailing whitespace handling when folding flow scalar lines, #307.
• Reject top-level block scalars without content indentation, #280.
• Ensure numbers survive round-trip, #737.
• Fix test coverage for issue #221.
• Fix flow scalar trailing whitespace folding, #307.
• Fix digits in YAML named tag handles.

Security

• Fix potential DoS via quadratic complexity in merge - deduplicate repeated elements (makes sense for malformed files > 10K).

[3.14.2] - 2025-11-15

Security

• Backported v4.1.1 fix to v3

[4.1.1] - 2025-11-12

Security

• Fix prototype pollution issue in yaml merge (<<) operator.

Commits

• 590dbab 4.2.0 released
• f944dc5 Add package.json funding field
• f692719 Changelog update
• 9971a06 Fix digits in YAML named tag handles
• 464a5b8 Fix flow scalar trailing whitespace folding, close #307
• 1fda4f7 Tests for #567, #565
• 031ad07 Stop resolving numbers with underscores as numeric scalars, #627
• e46d223 CI config update
• 9023fee Add lockfile
• 990e6f4 Docs update
• Additional commits viewable in compare view

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Summary by cubic

Upgrade js-yaml to 4.2.0 to pick up security hardening and parsing fixes in our dev tooling. This may slightly change how some YAML is parsed during builds/tests.

• Dependencies

  • Bump js-yaml 4.1.0 → 4.2.0.
  • Security: mitigates DoS in YAML merges; includes prior merge pollution fix.
  • Parsing: numbers with underscores no longer parse as numeric; stricter scalar/whitespace handling.

• Migration

  • If YAML uses values like 1_000, they now parse as strings. Update tests/fixtures or schemas if needed.
  • If you rely on very deep/large merges, adjust loader options for maxDepth or maxMergeSeqLength in tooling.

^{Written for commit d35ec9a. Summary will update on new commits.}

[dependabot]

Superseded by #210.