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Round-trip fidelity

yarutsk reproduces the source text exactly for everything it understands. A loads followed by dumps gives back the original string byte-for-byte in the common case:

import yarutsk

src = """\
defaults: &base
  timeout: 30
  retries: 3

service:
  name: api
  config: *base
"""
assert yarutsk.dumps(yarutsk.loads(src)) == src

Specifically preserved

  • Scalar styles — plain, 'single-quoted', "double-quoted", literal block |, folded block >
  • Non-canonical scalars — yes/no/on/off, ~, Null, True/False, 0xFF, 0o77 — reproduced as written, not re-canonicalised to true/false/null/255
  • YAML tags — !!str, !!python/tuple, and any custom tag are emitted back verbatim
  • Anchors and aliases — &name on the anchor node and *name for references are preserved; the Python layer returns the resolved value transparently
  • Blank lines between mapping entries and sequence items
  • Explicit document markers — --- and ...
  • Document-level directives — %YAML 1.1, %TAG

What's not round-tripped

The cases where output diverges from input are documented on the Limitations page — primarily around 64-bit integer range, underscore-separated numeric literals, and the 255-blank-line cap.

The test suite in tests/test_roundtrip.py exercises the end-to-end load → dump path across all preserved features, including stream-based IO.