element-web/test/test-utils/predictableRandom.ts

29 lines
699 B
TypeScript

/*
Copyright 2024 New Vector Ltd.
Copyright 2023 The Matrix.org Foundation C.I.C.
SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
Please see LICENSE files in the repository root for full details.
*/
// Fake random strings to give a predictable snapshot for IDs
// Simple Xorshift random number generator with predictable ID
export class PredictableRandom {
private state: number;
constructor() {
this.state = 314159265;
}
get(): number {
this.state ^= this.state << 13;
this.state ^= this.state >> 17;
this.state ^= this.state << 5;
return this.state / 1073741823;
}
reset(): void {
this.state = 314159265;
}
}