Fallow - Codebase Intelligence

Version updated for https://github.com/fallow-rs/fallow to version v2.52.0.

  • This action is used across all versions by 15 repositories.

Action Type

This is a Composite action.

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Action Summary

Fallow is a static analysis tool for TypeScript and JavaScript codebases that identifies unused code, duplication, complexity, and architectural issues, as well as providing optional runtime insights into code execution paths in production. It helps developers streamline code reviews, clean up dead code, reduce redundancy, and maintain code quality, all with minimal configuration. Built with a project-wide understanding of the codebase, Fallow enables efficient codebase management and supports AI-assisted development workflows without embedding AI itself.

What’s Changed

Highlights

fallow dupes --group-by partitions clone groups by team / directory / package / section

The flag was validated since v2.51.0 (so --group-by owner without CODEOWNERS produced a consistent error across check / health / dupes) but the resolver was built and discarded; output stayed ungrouped. v2.52.0 wires it through every output format.

fallow dupes --group-by owner --format json | jq '.groups[] | {key, total: .stats.duplicated_lines}'

Multi-owner attribution uses largest-owner with alphabetical tiebreak. A clone group with 5 instances split 4 in team-a/ and 1 in team-b/ is attributed to team-a. Per-instance owners are surfaced inline so consumers can see split ownership without re-resolving paths.

Output shape:

  • JSON: top-level grouped_by, total_issues, groups array with per-bucket stats / clone_groups (each carrying primary_owner) / clone_families. Schema additive; ungrouped output is unchanged.
  • SARIF: properties.group per result.
  • CodeClimate: top-level group per issue.
  • Human: cyan-bullet Per-{mode} duplication header, per-bucket sub-headers with stats. The largest-owner attribution preamble renders only for --group-by owner; directory / package / section modes hide it.

--top skips when --group-by is active so per-bucket stats reflect the full bucket; the renderer applies its own per-bucket cap.

BoundaryZone.root for monorepo per-package boundaries

[[boundaries.zones]]
name = "ui"
patterns = ["src/**"]
root = "packages/app/"

[[boundaries.zones]]
name = "domain"
patterns = ["src/**"]
root = "packages/core/"

The zone’s patterns resolve relative to the subtree instead of the project root. packages/app/src/login.tsx classifies as ui; packages/core/src/order.ts classifies as domain. Without root, these two zones with identical src/** patterns would have collided. Filter approach over prefix-rewriting: zero-cost for zones without root, keeps stored pattern strings un-corrupted.

Closes the FALLOW-BOUNDARY-ROOT-RESERVED warning ramp from v2.51.0. Patterns that double-prefix the root (e.g., root: "packages/app/" + patterns: ["packages/app/src/**"]) get a FALLOW-BOUNDARY-ROOT-REDUNDANT-PREFIX migration cue. Validation matches the existing validate_zone_references log-and-continue convention; a --strict-config follow-up to escalate to non-zero exit is tracked internally.

New ADR: decisions/007-boundary-zone-root.md.

Inline Angular @Component({ template: \…` })` complexity findings

v2.51.0 emitted synthetic <template> complexity for standalone .html files referenced via templateUrl only. v2.52.0 covers inline templates too, anchoring the finding at the host file’s @Component/@Directive decorator line so jump-to-source lands on the decorator and // fallow-ignore-next-line complexity placed directly above it suppresses without extra plumbing. Cache version bumped to 49 so existing caches re-extract.

Closes #187.

Changed

  • Schema version policy documented explicitly in docs/output-schema.json. Additive changes (new optional fields) do NOT bump; breaking changes do. Consumers should feature-detect new fields via JSON-key existence rather than gating on the version.

Fixed

  • cargo doc --workspace --no-deps --document-private-items now passes again. Three pre-existing rustdoc errors landed alongside the inline-template work: a bare <template> HTML tag in a doc comment, an unresolved [VitalSigns] / [HealthScore] intra-doc link, and a public-doc-links-private warning. CI is green.

Full Changelog: https://github.com/fallow-rs/fallow/compare/v2.51.0...v2.52.0