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@finos/legend-shared

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/** * Copyright (c) 2020-present, Goldman Sachs * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import seedrandom from 'seedrandom'; export class Randomizer { rng = seedrandom(); /** * This method is exposed to allow setting seeds in test. * NOTE: Disable this during production for security. */ setSeed(seed) { // eslint-disable-next-line no-process-env if (process.env.NODE_ENV === 'production') { return; } this.rng = seedrandom(seed); } /** * Get a random float in internal [0,1] */ getRandomFloat() { // NOTE: the randomizer library we use automatically guarantee the value lies within the interval [0,1] // but we do this just in case return Math.abs(this.rng.quick() % 1); } /** * Get a random double in internal [0,1] */ getRandomDouble() { // NOTE: the randomizer library we use automatically guarantee the value lies within the interval [0,1] // but we do this just in case return Math.abs(this.rng.double() % 1); } getRandomSignedInteger() { return this.rng.int32(); } /** * Return whole number in internal [0, max] if `max` is specified, or otherwise, [0, Infinity) */ getRandomWholeNumber(max) { return max !== undefined ? Math.abs(Math.floor(this.getRandomFloat() * Math.floor(max))) : Math.abs(this.getRandomSignedInteger()); } getRandomItemInCollection(collection) { return collection[this.getRandomWholeNumber(collection.length - 1)]; } getRandomDate(start, end) { return new Date(start.getTime() + Math.floor(this.getRandomFloat() * (end.getTime() - start.getTime()))); } } //# sourceMappingURL=RandomizerUtils.js.map