/**
 * Copyright 2019 Google Inc. All Rights Reserved.
 * 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 { Transform } from "../types.js" ; typeparam param ms returns export function debounce < T > ( ms ) { let timeout ; let timeoutP ; let savedChunk ; return new TransformStream ( { transform ( chunk , controller ) { savedChunk = chunk ; if ( timeout > 0 ) { clearTimeout ( timeout ) ; } timeoutP = new Promise ( resolve => { timeout = setTimeout ( ( ) => { controller . enqueue ( savedChunk ) ; timeout = 0 ; resolve ( undefined ) ; } , ms ) ; } ) ; } , async flush ( ) { await timeoutP ; } } , { highWaterMark : 1 } , { highWaterMark : 0 } ) ; }