v0.4.1

[IKrysanov]

0.4.1 - 2026-06-06

Fixed

• TestRunResult.cases is now a tuple[CaseResult, ...] instead of a
  list, so the frozen=True claim on the dataclass is honest.
  Before this change, frozen=True only blocked attribute
  reassignment (result.cases = [...]); the list itself remained
  mutable so result.cases.append(...) silently modified a
  "frozen" instance. A __post_init__ coerces any iterable the
  caller passes (list, generator, etc.) into a tuple, so the existing
  parsers that accumulate cases via .append on a local list and
  pass it through continue to work without change. Breaking only
  for external code that depended on the mutability of result.cases
  -- which was the bug we're fixing.
• JSONResultParser and JUnitResultParser now produce identical
  failed_node_ids for the same suite. The JSON parser previously
  emitted pytest's native form ("tests/test_x.py::test_y") while
  the JUnit parser emitted the dotted JUnit-XML form
  ("tests.test_x::test_y"), making downstream consumers (Airflow
  branches reading XCom, alerting that diffs the list across runs)
  silently parser-dependent. The JSON parser is now normalised to the
  same dotted form as JUnit. Breaking for any consumer that pinned
  on the slash form coming out of JSONResultParser since 0.4.0 --
  they get the new format starting with this release. The conversion
  direction was chosen for information-preservation: from the slash
  path with .py we can always derive the dotted module, but the
  reverse from JUnit's classname alone is ambiguous (module.Class
  vs module.subname).
• JUnitResultParser.parse no longer catches Exception from the
  underlying XML parser. The handler now lists exactly the exception
  types that a JUnit parse can legitimately fail with:
  xml.etree.ElementTree.ParseError (malformed XML),
  ValueError (covers every defusedxml security exception via
  DefusedXmlException), and OSError (file became unreadable
  between our exists() check and the actual read). Anything else
  -- MemoryError, AttributeError from a bug in our code,
  RecursionError -- now escapes the parser uncaught so the worker
  logs the real problem instead of seeing a misleading
  "Failed to parse JUnit report" message.
• JSONResultParser now reports per-case time as the sum of the
  setup + call + teardown phase durations from
  pytest-json-report, instead of reading only the call phase.
  Previously, a case that errored during setup (e.g. a fixture
  raised) had no call section in the JSON document and ended up
  with time=0.0 -- making per-case timings misleading exactly for
  the failures users most want to investigate. The new behaviour
  matches what pytest's own JUnit XML writer reports as the case
  time and so restores parity with :class:JUnitResultParser.
  Malformed durations on individual phases are still tolerated: that
  phase contributes 0 and the others are summed as usual.

Changed

• SubprocessPytestRunner drainer threads now count the per-stream
  output cap via len(chunk) (character count) instead of
  len(chunk.encode("utf-8", errors="replace")). The previous
  implementation allocated a throwaway bytes object on every
  readline() -- tens of thousands of allocations on a verbose
  suite -- just to get a precise byte count. len(chunk) is an
  O(1) cached lookup on str. The trade-off is that the cap is now
  an approximate byte count: exact for ASCII output (which is what
  pytest emits in practically all cases), under-counting bytes by up
  to 4x for UTF-8 multi-byte content. The cap parameter is still
  named max_output_bytes for back-compat; the docstring
  documents the approximation. Microbench on a 10k-line ASCII/Cyrillic
  mix: 41ms -> 14ms per 50 iterations (~3x speedup) with a 1.002x
  under-count ratio.
• TestRunResult.to_xcom no longer goes through dataclasses.asdict.
  The previous implementation recursively converted every nested
  :class:CaseResult into a dict tree before discarding the whole
  cases entry; for suites with thousands of tests that's a real
  amount of CPU and short-lived garbage on the worker. The new path
  builds the payload field-by-field, ~30x faster on a 5k-case suite
  (~227ms -> ~7ms in a microbench; bigger speedup on larger suites
  due to the per-case dataclass-to-dict overhead). The wire format is
  unchanged. A new structural test pins the set of XCom keys against
  the :class:TestRunResult schema so any future field addition is a
  conscious choice rather than a silent omission.

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This discussion was created from the release v0.4.1.