'use strict';

// These flags can be in a @gate pragma to declare that a test depends on

// certain conditions. They're like GKs.

//

// Examples:

//   // @gate enableSomeAPI

//   test('uses an unstable API', () => {/*...*/})

//

//   // @gate __DEV__

//   test('only passes in development', () => {/*...*/})

//

// Most flags are defined in ReactFeatureFlags. If it's defined there, you don't

// have to do anything extra here.

//

// There are also flags based on the environment, like __DEV__. Feel free to

// add new flags and aliases below.

//

// You can also combine flags using multiple gates:

//

//   // @gate enableSomeAPI

//   // @gate __DEV__

//   test('both conditions must pass', () => {/*...*/})

//

// Or using logical operators

//   // @gate enableSomeAPI && __DEV__

//   test('both conditions must pass', () => {/*...*/})

//

// Negation also works:

//   // @gate !deprecateLegacyContext

//   test('uses a deprecated feature', () => {/*...*/})

// These flags are based on the environment and don't change for the entire

// test run.

const environmentFlags = {

  __DEV__,

  build: __DEV__ ? 'development' : 'production',

  // TODO: Should "experimental" also imply "modern"? Maybe we should

  // always compare to the channel?

  experimental: __EXPERIMENTAL__,

  // Similarly, should stable imply "classic"?

  stable: !__EXPERIMENTAL__,

  variant: __VARIANT__,

  persistent: global.__PERSISTENT__ === true,

  // Use this for tests that are known to be broken.

  FIXME: false,

  TODO: false,

  // Turn these flags back on (or delete) once the effect list is removed in

  // favor of a depth-first traversal using `subtreeTags`.

  dfsEffectsRefactor: true,

  enableUseJSStackToTrackPassiveDurations: false,

};

function getTestFlags() {

  // These are required on demand because some of our tests mutate them. We try

  // not to but there are exceptions.

  const featureFlags = require('shared/ReactFeatureFlags');

  const schedulerFeatureFlags = require('scheduler/src/SchedulerFeatureFlags');

  const www = global.__WWW__ === true;

  const releaseChannel = www

    ? __EXPERIMENTAL__

      ? 'modern'

      : 'classic'

    : __EXPERIMENTAL__

    ? 'experimental'

    : 'stable';

  // Return a proxy so we can throw if you attempt to access a flag that

  // doesn't exist.

  return new Proxy(

    {

      channel: releaseChannel,

      modern: releaseChannel === 'modern',

      classic: releaseChannel === 'classic',

      source: !process.env.IS_BUILD,

      www,

      // This isn't a flag, just a useful alias for tests.

      enableActivity: releaseChannel === 'experimental' || www,

      enableUseSyncExternalStoreShim: !__VARIANT__,

      enableSuspenseList: releaseChannel === 'experimental' || www,

      enableLegacyHidden: www,

      // If there's a naming conflict between scheduler and React feature flags, the

      // React ones take precedence.

      // TODO: Maybe we should error on conflicts? Or we could namespace

      // the flags

      ...schedulerFeatureFlags,

      ...featureFlags,

      ...environmentFlags,

    },

    {

      get(flags, flagName) {

        const flagValue = flags[flagName];

        if (flagValue === undefined && typeof flagName === 'string') {

          throw Error(

            `Feature flag "${flagName}" does not exist. See TestFlags.js ` +

              'for more details.'

          );

        }

        return flagValue;

      },

    }

  );

}

exports.getTestFlags = getTestFlags;