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'use strict';
const assert = require('assert');const eachAsync = require('../../lib/helpers/cursor/eachAsync');
describe('eachAsync()', function() {  it('exhausts large cursor without parallel calls (gh-8235)', function() {    this.timeout(10000);
    let numInProgress = 0;    let num = 0;    const max = 1000;    let processed = 0;
    function next(cb) {      assert.equal(numInProgress, 0);      ++numInProgress;      setTimeout(function() {        --numInProgress;        if (num++ >= max) {          return cb(null, null);        }        cb(null, { name: `doc${num}` });      }, 0);    }
    return eachAsync(next, () => Promise.resolve(++processed), { parallel: 8 }).      then(() => assert.equal(processed, max));  });
  it('waits until the end before resolving the promise (gh-8352)', function() {    const max = 2;    let numCalled = 0;    let numDone = 0;    function next(cb) {      setImmediate(() => {        if (++numCalled > max) {          return cb(null, null);        }        cb(null, { num: numCalled });      });    }
    function fn() {      return new Promise(resolve => {        setTimeout(() => {          ++numDone;          resolve();        }, 100);      });    }
    return eachAsync(next, fn, { parallel: 3 }).      then(() => assert.equal(numDone, max)).      then(() => {        numCalled = 0;        numDone = 0;      }).      then(() => eachAsync(next, fn, { parallel: 2 })).      then(() => assert.equal(numDone, max));  });
  it('it processes the documents in batches successfully', () => {    const batchSize = 3;    let numberOfDocuments = 0;    const maxNumberOfDocuments = 9;    let numberOfBatchesProcessed = 0;
    function next(cb) {      setTimeout(() => {        if (++numberOfDocuments > maxNumberOfDocuments) {          cb(null, null);        }        return cb(null, { id: numberOfDocuments });      }, 0);    }
    const fn = (docs, index) => {      assert.equal(docs.length, batchSize);      assert.equal(index, numberOfBatchesProcessed++);    };
    return eachAsync(next, fn, { batchSize });  });
  it('it processes the documents in batches even if the batch size % document count is not zero successfully', () => {    const batchSize = 3;    let numberOfDocuments = 0;    const maxNumberOfDocuments = 10;    let numberOfBatchesProcessed = 0;
    function next(cb) {      setTimeout(() => {        if (++numberOfDocuments > maxNumberOfDocuments) {          cb(null, null);        }        return cb(null, { id: numberOfDocuments });      }, 0);    }
    const fn = (docs, index) => {      assert.equal(index, numberOfBatchesProcessed++);      if (index == 3) {        assert.equal(docs.length, 1);      }      else {        assert.equal(docs.length, batchSize);      }    };
    return eachAsync(next, fn, { batchSize });  });
  it('it processes the documents in batches with the parallel option provided', () => {    const batchSize = 3;    const parallel = 3;    let numberOfDocuments = 0;    const maxNumberOfDocuments = 9;    let numberOfBatchesProcessed = 0;
    function next(cb) {      setTimeout(() => {        if (++numberOfDocuments > maxNumberOfDocuments) {          cb(null, null);        }        return cb(null, { id: numberOfDocuments });      }, 0);    }
    const fn = (docs, index) => {      assert.equal(index, numberOfBatchesProcessed++);      assert.equal(docs.length, batchSize);    };
    return eachAsync(next, fn, { batchSize, parallel });  });
  it('executes all documents and aggregates errors if continueOnError set (gh-6355)', async() => {    const max = 3;    let numCalled = 0;    function next(cb) {      setImmediate(() => {        if (++numCalled > max) {          return cb(null, null);        }        cb(null, { num: numCalled });      });    }
    function fn(doc) {      return doc.num % 2 === 1 ? Promise.reject(new Error(`Doc number ${doc.num}`)) : null;    }
    const err = await eachAsync(next, fn, { continueOnError: true }).then(() => null, err => err);    assert.ok(err);    assert.equal(err.name, 'EachAsyncMultiError');    assert.ok(err.message.includes('Doc number 1'));    assert.ok(err.message.includes('Doc number 3'));    assert.equal(err.errors.length, 2);    assert.equal(err.errors[0].message, 'Doc number 1');    assert.equal(err.errors[1].message, 'Doc number 3');  });
  it('returns aggregated error fetching documents with continueOnError (gh-6355)', async() => {    const max = 3;    let numCalled = 0;    function next(cb) {      setImmediate(() => {        if (++numCalled > max) {          return cb(null, null);        }        if (numCalled % 2 === 1) {          return cb(new Error(`Fetching doc ${numCalled}`));        }        cb(null, { num: numCalled });      });    }
    function fn() {      return null;    }
    const err = await eachAsync(next, fn, { continueOnError: true }).then(() => null, err => err);    assert.ok(err);    assert.equal(err.name, 'EachAsyncMultiError', err);    assert.ok(err.message.includes('Fetching doc 1'));    assert.equal(err.errors.length, 1);    assert.equal(err.errors[0].message, 'Fetching doc 1');    assert.equal(numCalled, 1);  });
  it('avoids mutating document batch with parallel (gh-12652)', async() => {    const max = 100;    let numCalled = 0;    function next(cb) {      setImmediate(() => {        if (++numCalled > max) {          return cb(null, null);        }        cb(null, { num: numCalled });      });    }
    let numDocsProcessed = 0;    async function fn(batch) {      numDocsProcessed += batch.length;      const length = batch.length;      await new Promise(resolve => setTimeout(resolve, 50));      assert.equal(batch.length, length);    }
    await eachAsync(next, fn, { parallel: 7, batchSize: 10 });    assert.equal(numDocsProcessed, max);  });
  it('using AbortSignal (gh-12173)', async function() {    if (typeof AbortController === 'undefined') {      return this.skip();    }
    const ac = new AbortController();    const signal = ac.signal;
    let numCalled = 0;    const abortAfter = 2;    let numNextCalls = 0;    let numFnCalls = 0;    function next(cb) {      ++numNextCalls;      setImmediate(() => {        if (numCalled++ === abortAfter) {          ac.abort();
          return setImmediate(() => {            cb(null, { num: numCalled });          });        }
        cb(null, { num: numCalled });      });    }
    await eachAsync(next, () => ++numFnCalls, { signal });
    assert.equal(numNextCalls, 3);    assert.equal(numCalled, 3);    assert.equal(numFnCalls, 2);  });});