All files / lib/internal/perf event_loop_delay.js

97.67% Statements 84/86
81.81% Branches 9/11
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 8729x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x 29x     29x 29x 29x 29x 29x 4x 4x 4x 3x 3x 3x 4x 29x 29x 29x 29x 29x 3x 3x 3x 2x 2x 2x 3x 29x 29x 29x 29x 29x 29x 29x 29x 17x 17x 17x 17x 17x 17x 17x 17x 3x 3x 3x 17x 17x 29x 29x  
'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;