All files / lib/internal/perf event_loop_delay.js

97.67% Statements 84/86
77.77% Branches 7/9
75% Functions 3/4
97.67% Lines 84/86

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 8719x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x 19x     19x 19x 19x 19x 19x 4x 4x 4x 4x 4x 4x 4x 19x 19x 19x 19x 19x 3x 3x 3x 3x 3x 3x 3x 19x 19x 19x 19x 19x 19x 19x 19x 17x 17x 17x 17x 17x 17x 17x 17x 3x 3x 3x 17x 17x 19x 19x  
'use strict';
const {
  ReflectConstruct,
  SafeMap,
  Symbol,
} = primordials;
 
const {
  codes: {
    ERR_ILLEGAL_CONSTRUCTOR,
    ERR_INVALID_THIS,
  }
} = require('internal/errors');
 
const {
  createELDHistogram,
} = internalBinding('performance');
 
const {
  validateInteger,
  validateObject,
} = require('internal/validators');
 
const {
  Histogram,
  kHandle,
  kMap,
} = require('internal/histogram');
 
const {
  makeTransferable,
} = require('internal/worker/js_transferable');
 
const kEnabled = Symbol('kEnabled');
 
class ELDHistogram extends Histogram {
  constructor(i) {
    throw new ERR_ILLEGAL_CONSTRUCTOR();
  }
 
  /**
   * @returns {boolean}
   */
  enable() {
    if (this[kEnabled] === undefined)
      throw new ERR_INVALID_THIS('ELDHistogram');
    if (this[kEnabled]) return false;
    this[kEnabled] = true;
    this[kHandle].start();
    return true;
  }
 
  /**
   * @returns {boolean}
   */
  disable() {
    if (this[kEnabled] === undefined)
      throw new ERR_INVALID_THIS('ELDHistogram');
    if (!this[kEnabled]) return false;
    this[kEnabled] = false;
    this[kHandle].stop();
    return true;
  }
}
 
/**
 * @param {{
 *   resolution : number
 * }} [options]
 * @returns {ELDHistogram}
 */
function monitorEventLoopDelay(options = {}) {
  validateObject(options, 'options');
 
  const { resolution = 10 } = options;
  validateInteger(resolution, 'options.resolution', 1);
 
  return makeTransferable(ReflectConstruct(
    function() {
      this[kEnabled] = false;
      this[kHandle] = createELDHistogram(resolution);
      this[kMap] = new SafeMap();
    }, [], ELDHistogram));
}
 
module.exports = monitorEventLoopDelay;