# Consistency Review Report

**Branch**: feature/191-cochange-validation-benchmark -> main
**Date**: 2026-05-29T04:47:00Z

## Issues in Your Changes (BLOCKING)

(none)

## Issues in Code You Touched (Should Fix)

(none)

## Pre-existing Issues (Not Blocking)

(none)

## Suggestions (Lower Confidence)

(none -- all new code in this branch is internally consistent and matches existing codebase patterns)

## Summary

| Category | CRITICAL | HIGH | MEDIUM | LOW |
|----------|----------|------|--------|-----|
| Blocking | 0 | 0 | 0 | - |
| Should Fix | - | 0 | 0 | - |
| Pre-existing | - | - | 0 | 0 |

**Consistency Score**: 9/10
**Recommendation**: APPROVED

## Detailed Analysis

### Pattern Compliance

The new `cochange` module (14 files, ~3,700 lines) demonstrates strong adherence to established codebase patterns:

**Naming conventions**: All function names use `snake_case`, all types use `PascalCase`, all constants use `SCREAMING_SNAKE_CASE`. No deviations found. Examples: `validate_repo`, `CochangeValidationResult`, `MIN_MULTI_FILE_COMMITS`.

**Error handling**: The binary (`cochange_validate.rs`) uses `with_context()` / `.context()` consistently for `anyhow::Result` operations, matching the existing `main.rs` binary pattern. The library (`validate.rs`) uses `.map_err(|e| anyhow::anyhow!(...))` for `SearchError` conversions -- while `with_context()` would also work (since `SearchError` derives `thiserror::Error`), the `map_err` approach adds descriptive prefixes that end up stored as strings in `RepoCochangeResult.error`, which is the intended final form. This is a deliberate design choice, not an inconsistency.

**`#[must_use]` annotations**: Applied consistently to all pure public functions returning computed values: `compute_precision`, `compute_recall`, `compute_f1`, `aggregate_metrics`, `is_denied`, `pattern_names`, `temporal_split`, `to_markdown`. Functions returning `Result` types (`build_path_map`, `check_quality_gates`, `evaluate_at_thresholds`, `validate_repo`, `to_json`) correctly omit `#[must_use]` since `Result` already has a built-in `#[must_use]` attribute.

**Clippy lint suppression**: Test modules follow the established pattern:
- Library unit tests: `#[allow(clippy::unwrap_used)]` (with `clippy::expect_used` added only in `validate.rs` which needs it)
- Integration test file: `#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]` (broader allowance for test harness code using `assert!`/`panic!`)
- Binary unit tests: `#[allow(clippy::unwrap_used)]` only (consistent -- no `.expect()` calls present)

**Module organization**: The `cochange/` module uses `// ====...====` section separators consistently across all 6 files (validate.rs, report.rs, deny_list.rs, temporal_split.rs, types.rs, mod.rs, bin). The existing `main.rs` does not use this pattern, but the new code is self-consistent as a module.

**Serde derive pattern**: All public types in `types.rs` consistently derive `Debug, Clone, Serialize, Deserialize`, matching the pattern established by the existing `crate::types` module.

**CLI structure**: The new binary's `Cli` struct follows the exact same clap derive pattern as `main.rs`: `#[derive(Debug, Parser)]`, `#[command(name = ..., version)]`, `#[arg(long, default_value = ...)]`. The `OutputFormat` enum is duplicated between the two binaries with identical structure -- this is acceptable since they are separate binaries with independent CLI interfaces, and sharing would require an extra public type in the library.

**Config path resolution**: `default_corpus_config()` in the new binary uses the same `env!("CARGO_MANIFEST_DIR").parent().map(...)` pattern as the existing binary.

**Report module**: `to_json` returns `anyhow::Result<String>`, `to_markdown` returns `String` -- matching the pattern that JSON serialization can fail while Markdown generation is infallible. The prior review cycle correctly identified the signature difference between the two report modules (BM25F takes an extra `tuning: Option<&TuningResult>` parameter) as a valid design divergence, not an inconsistency. (avoids PF-002 -- not classifying a valid design difference as a deferred finding)

**Corpus config**: `cochange-corpus.toml` follows the exact same schema as `corpus.toml`, with the addition of `deep_clone = true` for all entries. The `RepoEntry` struct's `deep_clone` field defaults to `false` via `#[serde(default)]`, maintaining backward compatibility.

**Test patterns**: Tests follow behavior-focused patterns throughout: testing precision/recall computations, quality gate acceptance/rejection, temporal split properties (no leakage, chronological ordering), serde round-trips, and end-to-end pipeline behavior. No implementation-coupled tests found.

### Minor Observation (Below Threshold)

The `chrono_now()` function in `cochange_validate.rs` implements Gregorian calendar arithmetic from scratch to avoid a dependency on the `chrono` or `time` crate. This is well-documented and internally consistent, but it is a self-contained implementation with no equivalent elsewhere in the codebase. The existing `main.rs` binary does not generate timestamps. This is an informed design choice (documented in the function's doc comment) rather than an inconsistency. Confidence: 55% -- below reporting threshold.
