/** * Copyright (c) Facebook, Inc. and its affiliates. * * This source code is licensed under the MIT license found in the * LICENSE file in the root directory of this source tree. * * @flow */ import { REACT_CONTEXT_TYPE, REACT_FORWARD_REF_TYPE, REACT_FRAGMENT_TYPE, REACT_PROFILER_TYPE, REACT_PROVIDER_TYPE, REACT_DEBUG_TRACING_MODE_TYPE, REACT_STRICT_MODE_TYPE, REACT_SUSPENSE_TYPE, REACT_SUSPENSE_LIST_TYPE, REACT_MEMO_TYPE, REACT_LAZY_TYPE, REACT_SCOPE_TYPE, REACT_LEGACY_HIDDEN_TYPE, REACT_OFFSCREEN_TYPE, REACT_CACHE_TYPE, REACT_TRACING_MARKER_TYPE, } from 'shared/ReactSymbols'; import { enableScopeAPI, enableCacheElement, enableTransitionTracing, enableDebugTracing, enableLegacyHidden, } from './ReactFeatureFlags'; const REACT_MODULE_REFERENCE: symbol = Symbol.for('react.module.reference'); export default function isValidElementType(type: mixed): boolean { if (typeof type === 'string' || typeof type === 'function') { return true; } // Note: typeof might be other than 'symbol' or 'number' (e.g. if it's a polyfill). if ( type === REACT_FRAGMENT_TYPE || type === REACT_PROFILER_TYPE || (enableDebugTracing && type === REACT_DEBUG_TRACING_MODE_TYPE) || type === REACT_STRICT_MODE_TYPE || type === REACT_SUSPENSE_TYPE || type === REACT_SUSPENSE_LIST_TYPE || (enableLegacyHidden && type === REACT_LEGACY_HIDDEN_TYPE) || type === REACT_OFFSCREEN_TYPE || (enableScopeAPI && type === REACT_SCOPE_TYPE) || (enableCacheElement && type === REACT_CACHE_TYPE) || (enableTransitionTracing && type === REACT_TRACING_MARKER_TYPE) ) { return true; } if (typeof type === 'object' && type !== null) { if ( type.$$typeof === REACT_LAZY_TYPE || type.$$typeof === REACT_MEMO_TYPE || type.$$typeof === REACT_PROVIDER_TYPE || type.$$typeof === REACT_CONTEXT_TYPE || type.$$typeof === REACT_FORWARD_REF_TYPE || // This needs to include all possible module reference object // types supported by any Flight configuration anywhere since // we don't know which Flight build this will end up being used // with. type.$$typeof === REACT_MODULE_REFERENCE || type.getModuleId !== undefined ) { return true; } } return false; }