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 8720x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x     20x 20x 20x 20x 20x 4x 4x 4x 4x 4x 4x 4x 20x 20x 20x 20x 20x 3x 3x 3x 3x 3x 3x 3x 20x 20x 20x 20x 20x 20x 20x 20x 17x 17x 17x 17x 17x 17x 17x 17x 3x 3x 3x 17x 17x 20x 20x  
'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;