infer options of boolean flags

[dferber90]

Infer options of boolean feature flags in generatePermutations.

Until now generatePermutations ignored boolean flags which did not explicitly declare their options like these

// flags.ts
import { flag } from '@vercel/flags/next';

export const showBanner = flag({
  key: 'banner',
  decide: () => false,
});

// a group of feature flags to be precomputed
export const marketingFlags = [showBanner] as const;

This PR fixes this by automatically inferring boolean options. The flag above would conceptually be the same as

export const showBanner = flag({
  key: 'banner',
  decide: () => false,
  options: [false, true]
});

Non-boolean flags should always declare all available options.

export const showBanner = flag<string>({
  key: 'banner',
  decide: () => "hello",
  options: ["hello", "hi"]
});

Pass a filter to generatePermutations(group, filter) to skip generation of certain combinations when using flags.

export async function generateStaticParams() {
  // second argument is the filter here
  const codes = await generatePermutations(rootFlags, permutation => permutation.exampleFlag === true);
  return codes.map((code) => ({ code }));
}

See Precomputing to learn more.

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
flags-sdk-snippets	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jan 20, 2025 2:50pm
summer-sale	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jan 20, 2025 2:50pm