35 lines
1 KiB
TypeScript
35 lines
1 KiB
TypeScript
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/*
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Copyright 2023 The Matrix.org Foundation C.I.C.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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// Fake random strings to give a predictable snapshot for IDs
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// Simple Xorshift random number generator with predictable ID
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export class PredictableRandom {
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private state: number;
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constructor() {
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this.state = 314159265;
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}
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get(): number {
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this.state ^= this.state << 13;
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this.state ^= this.state >> 17;
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this.state ^= this.state << 5;
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return this.state / 1073741823;
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}
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reset(): void {
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this.state = 314159265;
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}
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}
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