clean

$ GH_TOKEN=... npx redlinegate metrics score-seeds --repo <org>/<repo> --pr <n>

SEED <n> [BLOCKER|HIGH|SUGGESTION] (<stack>/<rule-slug>) <short description>

// Redline precision corpus. This file is deliberately CORRECT.
// Any review comment on it is a false positive. Zero findings is a pass.
//
// It is written to bait the common nitpick failures: unmemoised values, "missing" error
// handling on internal calls, direct index access, an effect that is genuinely necessary.
import { useCallback, useEffect, useRef, useState } from 'react';
import { useQuery } from '@tanstack/react-query';

type Plan = { id: string; label: string; priceMinor: number };

const formatter = new Intl.NumberFormat('en-GB', { style: 'currency', currency: 'GBP' });

async function fetchPlans(signal: AbortSignal): Promise<Plan[]> {
  const res = await fetch('/api/plans', { signal });
  if (!res.ok) throw new Error(`plans: ${res.status}`);
  return res.json();
}

export function PlanPicker({ onSelect }: { onSelect: (plan: Plan) => void }) {
  const [selectedId, setSelectedId] = useState<string | null>(null);
  const listRef = useRef<HTMLUListElement>(null);

  const { data: plans, error } = useQuery({
    queryKey: ['plans'],
    queryFn: ({ signal }) => fetchPlans(signal),
  });

  // Derived during render, not synced through an effect.
  const selected = plans?.find((plan) => plan.id === selectedId) ?? null;

  // A real external-system effect: focus is not derivable from render output.
  useEffect(() => {
    if (!selected) return;
    listRef.current?.focus();
  }, [selected]);

  const handleSelect = useCallback(
    (plan: Plan) => {
      setSelectedId(plan.id);
      onSelect(plan);
    },
    [onSelect]
  );

  if (error) return <p role="alert">Plans are unavailable right now.</p>;
  if (!plans) return <p>Loading plans…</p>;

  return (
    <ul ref={listRef} tabIndex={-1}>
      {plans.map((plan) => (
        <li key={plan.id}>
          <button type="button" onClick={() => handleSelect(plan)}>
            {plan.label} — {formatter.format(plan.priceMinor / 100)}
          </button>
        </li>
      ))}
      {plans.length === 0 ? <li>No plans available.</li> : null}
    </ul>
  );
}

// Redline precision corpus. This file is deliberately CORRECT.
// Any review comment on it is a false positive. Zero findings is a pass.
package clean

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"time"
)

var errUpstream = errors.New("upstream unavailable")

type Client struct {
	http *http.Client
	base string
}

func NewClient(base string) *Client {
	return &Client{
		http: &http.Client{Timeout: 3 * time.Second},
		base: base,
	}
}

type Balance struct {
	AccountID string `json:"accountId"`
	Minor     int64  `json:"minor"`
}

func (c *Client) Balance(ctx context.Context, accountID string) (Balance, error) {
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.base+"/balance/"+accountID, nil)
	if err != nil {
		return Balance{}, fmt.Errorf("build balance request: %w", err)
	}

	resp, err := c.http.Do(req)
	if err != nil {
		return Balance{}, fmt.Errorf("call balance: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return Balance{}, fmt.Errorf("balance status %d: %w", resp.StatusCode, errUpstream)
	}

	var balance Balance
	if err := json.NewDecoder(resp.Body).Decode(&balance); err != nil {
		return Balance{}, fmt.Errorf("decode balance: %w", err)
	}
	return balance, nil
}

// Handler is the HTTP boundary: it validates input and maps errors to statuses. The
// internal call above is trusted to return a typed error, so there is no second layer
// of defensive checking here.
func (c *Client) Handler(w http.ResponseWriter, r *http.Request) {
	accountID := r.URL.Query().Get("accountId")
	if accountID == "" {
		http.Error(w, "accountId is required", http.StatusBadRequest)
		return
	}

	balance, err := c.Balance(r.Context(), accountID)
	if errors.Is(err, errUpstream) {
		http.Error(w, "upstream unavailable", http.StatusBadGateway)
		return
	}
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	if err := json.NewEncoder(w).Encode(balance); err != nil {
		// The response is already partially written; there is nothing left to signal.
		return
	}
}