From 99c1d9af689e5325f3cf535c4007b3aeb8325229 Mon Sep 17 00:00:00 2001 From: Minteck Date: Tue, 10 Jan 2023 14:54:04 +0100 Subject: Update - This is an automated commit --- school/node_modules/w3c-hr-time/lib/performance.js | 53 ++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 school/node_modules/w3c-hr-time/lib/performance.js (limited to 'school/node_modules/w3c-hr-time/lib/performance.js') diff --git a/school/node_modules/w3c-hr-time/lib/performance.js b/school/node_modules/w3c-hr-time/lib/performance.js new file mode 100644 index 0000000..4bcfbc3 --- /dev/null +++ b/school/node_modules/w3c-hr-time/lib/performance.js @@ -0,0 +1,53 @@ +"use strict"; + +// Actual implementation of the Performance class. + +const clockIsAccurate = require("./clock-is-accurate"); +const calculateClockOffset = require("./calculate-clock-offset"); +const { hrtime, toMS } = require("./utils"); + +const kTimeOrigin = Symbol("time origin"); +const kTimeOriginTimestamp = Symbol("time origin timestamp"); + +class Performance { + constructor() { + // Time origin. + const timeOrigin = hrtime(); + this[kTimeOrigin] = timeOrigin; + + if (clockIsAccurate) { + // Let |t1| be the DOMHighResTimeStamp representing the high resolution Unix time at which the global monotonic + // clock is zero. This has to be calculated for every Performance object to account for clock drifts. + const t1 = calculateClockOffset(); + + // Let |t2| be the DOMHighResTimeStamp representing the high resolution time value of the global monotonic clock + // at global's time origin. + const t2 = toMS(timeOrigin); + + // Return the sum of |t1| and |t2|. + this[kTimeOriginTimestamp] = t1 + t2; + } else { + // Clock isn't accurate enough. Use millisecond accuracy per spec. + const cur = Date.now(); + this[kTimeOriginTimestamp] = cur; + } + } + + // The timeOrigin getter actually returns the time origin timestamp, not the raw time origin. + get timeOrigin() { + return this[kTimeOriginTimestamp]; + } + + now() { + const diff = toMS(hrtime(this[kTimeOrigin])); + return clockIsAccurate ? diff : Math.round(diff); + } + + toJSON() { + return { + timeOrigin: this.timeOrigin + }; + } +} + +module.exports = { Performance }; -- cgit