Scenario: Large noisy diff; only one relevant doc change

A developer made a large refactor touching many files and hundreds of lines. Only one change is documentation-relevant: a documented Python function parse_config gained a new optional parameter strict: bool = False. The remaining changes are internal refactors, test updates, and configuration changes with no docstrings.

Your job is to find the one in-scope change without false positives.

Setup

Extract the following file and set up the git repository:

=============== FILE: inputs/setup.sh =============== #!/usr/bin/env bash set -euo pipefail

git init git config user.email "dev@example.com" git config user.name "Dev"

mkdir -p src tests config

cat > src/config_parser.py << 'PYEOF' from future import annotations

def parse_config(path: str) -> dict: """Parse a config file into a dict.

Args:
    path: Path to a KEY=VALUE config file.

Returns:
    Parsed key-value pairs.
"""
out: dict[str, str] = {}
with open(path, "r", encoding="utf-8") as f:
    for line in f.read().splitlines():
        if not line.strip() or line.strip().startswith("#"):
            continue
        if "=" not in line:
            continue
        k, _, v = line.partition("=")
        out[k.strip()] = v.strip()
return out

PYEOF

Create lots of noise files (undocumented) to simulate a large refactor.

for i in $(seq 1 11); do cat > "src/noise_${i}.py" <<'PYEOF' from future import annotations

def internal_transform(x: int) -> int: # Internal helper: intentionally undocumented. total = 0 for n in range(25): total += (x + n) % 7 # Pretend this file is large. blob = """ line01 line02 line03 line04 line05 line06 line07 line08 line09 line10 line11 line12 line13 line14 line15 line16 line17 line18 line19 line20 line21 line22 line23 line24 line25 """ _ = blob return total PYEOF

done

cat > tests/test_noise.py << 'PYEOF' def test_smoke(): assert True PYEOF

cat > config/app.toml << 'EOF'

Placeholder config file

mode = "dev" EOF

git add -A && git commit -m "baseline noisy repo"

Working tree change: ONLY parse_config is a doc-relevant change.

cat > src/config_parser.py << 'PYEOF' from future import annotations

def parse_config(path: str, strict: bool = False) -> dict: """Parse a config file into a dict.

Args:
    path: Path to a KEY=VALUE config file.

Returns:
    Parsed key-value pairs.
"""
out: dict[str, str] = {}
with open(path, "r", encoding="utf-8") as f:
    for line in f.read().splitlines():
        if not line.strip() or line.strip().startswith("#"):
            continue
        if "=" not in line:
            if strict:
                raise ValueError("invalid line")
            continue
        k, _, v = line.partition("=")
        out[k.strip()] = v.strip()
return out

PYEOF

Additional noise changes (no docstrings anywhere).

for i in $(seq 1 4); do sed -i '' 's/range(25)/range(30)/' "src/noise_${i}.py" || true printf '\n# refactor note %s\n' "$i" >> "src/noise_${i}.py" done

printf '\n# touched by refactor\n' >> config/app.toml

Output Specification

Sync the documentation and write the results to doc-sync-report.md.