Release 0.2.2: a wrong content guess is UnknownFormat, not a misleading parse error

[copyleftdev]

Found while running anomalyx against real datasets (an Apache error_log): a
plain-text line that merely starts with [ got claimed by the JSON parser's
cheap leading-[/{ sniff, and when the JSON parse then failed the user saw
failed to parse json input — pointing them at the wrong problem.

Fix

ParserRegistry::normalize now tracks how the parser was resolved:

• A parse failure under a weak (TEXT/FALLBACK) content sniff → the guess
  was wrong → AxError::UnknownFormat ("I don't recognize this").
• A format identified confidently — by file extension, or a MAGIC/STRONG
  signature — still surfaces a genuine malformed-file parse error unchanged
  (a broken .json or a truncated Parquet still says so).

resolve() is unchanged; resolve_detail() is the new internal helper.

Tests pin all three paths (weak-sniff→UnknownFormat, extension→Parse,
STRONG-sniff→Parse) and the < STRONG boundary. Mutation gate on the changed
file: 0 surviving mutants. Bumps 0.2.1 → 0.2.2.

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes

  • Fixed JSON content sniffing to correctly report unknown format instead of parse errors when format detection confidence is low.

• Chores

  • Version bumped to 0.2.2.

[coderabbitai]

Caution

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Pull request was closed or merged during review

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 02eee817-8276-4096-823a-c0044b4cd34f

📥 Commits

Reviewing files that changed from the base of the PR and between d4c8ce8 and 005a28d.

⛔ Files ignored due to path filters (1)

• Cargo.lock is excluded by !**/*.lock

📒 Files selected for processing (3)

• CHANGELOG.md
• Cargo.toml
• crates/ax-normalize/src/parser.rs

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📝 Walkthrough

Walkthrough

This PR refactors the parser registry to classify JSON content sniffing errors more accurately. When content detection yields a weak confidence score and parsing fails, the error now reports UnknownFormat rather than a misleading format-specific parse error. Strong signatures and explicit extensions preserve original parse errors. Version bumped to 0.2.2 with updated documentation.

Changes

JSON Parser Error Classification

Layer / File(s)	Summary
Weak Sniff Error Classification crates/ax-normalize/src/parser.rs	New Resolution enum tracks parser selection method (extension vs sniff). resolve_detail helper returns parser paired with selection confidence. normalize refactored to map weak-sniff parse failures to UnknownFormat, while extension and strong-sniff parse failures surface original errors. Tests validate weak sniff, strong sniff, and extension-based behaviors.
Version 0.2.2 Release Documentation CHANGELOG.md, Cargo.toml	Changelog documents weak sniff error classification fix dated 2026-05-31. Workspace version and internal dependencies (ax-core, ax-normalize, ax-detect) updated from 0.2.1 to 0.2.2. Release comparison links updated.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Poem

🐰 A parser's whisper, once confused with shout,
Now knows when sniffs are weak—no doubt!
Strong JSON still screams its parsing woe,
While weak guesses gracefully let unknowns go. ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and specifically describes the main change: fixing how weak content sniffs handle parsing failures by reporting UnknownFormat instead of misleading parse errors, which aligns perfectly with the core change across all modified files (version bump, changelog, and parser logic refactor).
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/weak-sniff-unknown-0.2.2

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