# Complexity Review Report

**Branch**: feat-183-hotspot-and-risk-scoring -> main
**Date**: 2026-05-25T14:29

## Issues in Your Changes (BLOCKING)

No blocking issues found.

## Issues in Code You Touched (Should Fix)

No should-fix issues found.

## Pre-existing Issues (Not Blocking)

No pre-existing issues found.

## Suggestions (Lower Confidence)

No suggestions.

## Summary

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

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

## Detailed Analysis

### Function Complexity Metrics

| Function | Lines | Nesting | Params | Cyclomatic | Verdict |
|----------|-------|---------|--------|------------|---------|
| `decay_weight` | 3 | 0 | 2 | 1 | Excellent |
| `compute_file_risk_scores` | ~50 | 2 (for + if) | 3 | 5 | Good |

### Rationale

This PR introduces exemplary low-complexity code. Every metric falls comfortably within "Good" thresholds:

**`decay_weight` (scoring.rs:46-49)**: 3 lines, single expression, no branching. Pure function with `#[inline]`, `#[must_use]`, and a `debug_assert!` guard. Textbook simplicity.

**`compute_file_risk_scores` (scoring.rs:76-150)**: ~50 lines with max nesting depth of 2 (one `for` loop containing one `if`). Three clear phases (pre-classify, accumulate, normalize) are separated by comments and blank lines, making the algorithm scannable in a single pass. The function sits exactly at the "warning" threshold for length (50 lines) but the three-phase decomposition keeps cognitive load low -- each phase is independently understandable.

**`FileRiskScores` (types.rs:268-274)**: Plain data struct with two `f64` fields. No behavior, no complexity.

**Magic values**: The two numeric literals (`86_400` for seconds-per-day, `50_000` for capacity cap) are documented by comments and are domain-standard constants. The feature knowledge confirms these are intentional. The underscore separators (`86_400`, `50_000`) improve readability over raw `86400`.

**Boolean complexity**: The only boolean condition is `if is_fix` (line 115), which is a pre-computed flag -- no compound boolean expressions anywhere.

**Test file (scoring_tests.rs, 536 lines)**: Well-organized into 6 named groups with clear section headers. Each test is short and focused on a single behavior. The `make_commit` helper and `approx_eq` utility keep test infrastructure minimal. The file length is appropriate for 25 tests covering a non-trivial algorithm.

**Naming**: All functions, constants, and variables have self-documenting names (`half_life_days`, `weighted_total`, `fix_density`, `max_total`). No abbreviations that require mental lookup.

**Parameter counts**: Both public functions take 2-3 parameters, well within the "Good" threshold.
