This release adds 4 new functions: UnmarshalFirst, Diagnose, DiagnoseFirst, and Wellformed. In addition Valid function is deprecated (use Wellformed instead).

• UnmarshalFirst decodes first CBOR data item and returns remaining bytes. This is useful for CBOR Sequences (RFC 8742) and also because Unmarshal was fixed in v2.5.0-beta to return ExtraneousDataError if there are remaining bytes.
• Diagnose and DiagnoseFirst returns human-readable Extended Diagnostic Notation (RFC 8610 Appendix G) for the given CBOR encoding. These are useful for debugging and allows more user-friendly error logging.

What's Changed (since v2.5.0-beta2)

• Deprecate Valid() and add Wellformed() to replace it by @fxamacker in https://github.com/fxamacker/cbor/pull/400
• Add UnmarshalFirst by @immesys in https://github.com/fxamacker/cbor/pull/398
• Add UnmarshalFirst to DecMode interface by @fxamacker in https://github.com/fxamacker/cbor/pull/402
• Add functions for Extended Diagnostic Notation (RFC 8610 Appendix G) by @zensh in https://github.com/fxamacker/cbor/pull/386
• Add more tests for Diagnose and DiagnoseFirst by @fxamacker in https://github.com/fxamacker/cbor/pull/405

Changes to CI and Documentation

• Create govulncheck.yml by @fxamacker in https://github.com/fxamacker/cbor/pull/393
• Update README for cbor v2.5.0-beta2 by @fxamacker in https://github.com/fxamacker/cbor/pull/394
• Bump actions/setup-go from 3 to 4 by @dependabot in https://github.com/fxamacker/cbor/pull/395
• Update ci-go-cover.yml by @x448 in https://github.com/fxamacker/cbor/pull/404
• Update README for CBOR Sequences RFC 8742 by @fxamacker in https://github.com/fxamacker/cbor/pull/406
• Update README.md for v2.5.0-beta3 by @fxamacker in https://github.com/fxamacker/cbor/pull/407

Special Thanks

Thank you @immesys, @zensh, and @x448 for your contributions!

Full Changelog: https://github.com/fxamacker/cbor/compare/v2.5.0-beta2...v2.5.0-beta3