source: frontend/node_modules/webpack/lib/logging/Logger.js

/*
        MIT License http://www.opensource.org/licenses/mit-license.php
        Author Tobias Koppers @sokra
*/

"use strict";

const LogType = Object.freeze({
        error: /** @type {"error"} */ ("error"), // message, c style arguments
        warn: /** @type {"warn"} */ ("warn"), // message, c style arguments
        info: /** @type {"info"} */ ("info"), // message, c style arguments
        log: /** @type {"log"} */ ("log"), // message, c style arguments
        debug: /** @type {"debug"} */ ("debug"), // message, c style arguments

        trace: /** @type {"trace"} */ ("trace"), // no arguments

        group: /** @type {"group"} */ ("group"), // [label]
        groupCollapsed: /** @type {"groupCollapsed"} */ ("groupCollapsed"), // [label]
        groupEnd: /** @type {"groupEnd"} */ ("groupEnd"), // [label]

        profile: /** @type {"profile"} */ ("profile"), // [profileName]
        profileEnd: /** @type {"profileEnd"} */ ("profileEnd"), // [profileName]

        time: /** @type {"time"} */ ("time"), // name, time as [seconds, nanoseconds]

        clear: /** @type {"clear"} */ ("clear"), // no arguments
        status: /** @type {"status"} */ ("status") // message, arguments
});

module.exports.LogType = LogType;

/** @typedef {typeof LogType[keyof typeof LogType]} LogTypeEnum */
/** @typedef {Map<string | undefined, [number, number]>} TimersMap */

const LOG_SYMBOL = Symbol("webpack logger raw log method");
const TIMERS_SYMBOL = Symbol("webpack logger times");
const TIMERS_AGGREGATES_SYMBOL = Symbol("webpack logger aggregated times");

/** @typedef {EXPECTED_ANY[]} Args */
/** @typedef {(type: LogTypeEnum, args?: Args) => void} LogFn */
/** @typedef {(name: string | (() => string)) => WebpackLogger} GetChildLogger */

class WebpackLogger {
        /**
         * Creates an instance of WebpackLogger.
         * @param {LogFn} log log function
         * @param {GetChildLogger} getChildLogger function to create child logger
         */
        constructor(log, getChildLogger) {
                /** @type {LogFn} */
                this[LOG_SYMBOL] = log;
                /** @type {GetChildLogger} */
                this.getChildLogger = getChildLogger;
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        error(...args) {
                this[LOG_SYMBOL](LogType.error, args);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        warn(...args) {
                this[LOG_SYMBOL](LogType.warn, args);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        info(...args) {
                this[LOG_SYMBOL](LogType.info, args);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        log(...args) {
                this[LOG_SYMBOL](LogType.log, args);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        debug(...args) {
                this[LOG_SYMBOL](LogType.debug, args);
        }

        /**
         * Processes the provided condition.
         * @param {boolean=} condition condition
         * @param {Args} args args
         */
        assert(condition, ...args) {
                if (!condition) {
                        this[LOG_SYMBOL](LogType.error, args);
                }
        }

        trace() {
                this[LOG_SYMBOL](LogType.trace, ["Trace"]);
        }

        clear() {
                this[LOG_SYMBOL](LogType.clear);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        status(...args) {
                this[LOG_SYMBOL](LogType.status, args);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        group(...args) {
                this[LOG_SYMBOL](LogType.group, args);
        }

        /**
         * Processes the provided arg.
         * @param {Args} args args
         */
        groupCollapsed(...args) {
                this[LOG_SYMBOL](LogType.groupCollapsed, args);
        }

        groupEnd() {
                this[LOG_SYMBOL](LogType.groupEnd);
        }

        /**
         * Processes the provided label.
         * @param {string=} label label
         */
        profile(label) {
                this[LOG_SYMBOL](LogType.profile, [label]);
        }

        /**
         * Processes the provided label.
         * @param {string=} label label
         */
        profileEnd(label) {
                this[LOG_SYMBOL](LogType.profileEnd, [label]);
        }

        /**
         * Processes the provided label.
         * @param {string} label label
         */
        time(label) {
                /** @type {TimersMap} */
                this[TIMERS_SYMBOL] = this[TIMERS_SYMBOL] || new Map();
                this[TIMERS_SYMBOL].set(label, process.hrtime());
        }

        /**
         * Processes the provided label.
         * @param {string=} label label
         */
        timeLog(label) {
                const prev = this[TIMERS_SYMBOL] && this[TIMERS_SYMBOL].get(label);
                if (!prev) {
                        throw new Error(`No such label '${label}' for WebpackLogger.timeLog()`);
                }
                const time = process.hrtime(prev);
                this[LOG_SYMBOL](LogType.time, [label, ...time]);
        }

        /**
         * Processes the provided label.
         * @param {string=} label label
         */
        timeEnd(label) {
                const prev = this[TIMERS_SYMBOL] && this[TIMERS_SYMBOL].get(label);
                if (!prev) {
                        throw new Error(`No such label '${label}' for WebpackLogger.timeEnd()`);
                }
                const time = process.hrtime(prev);
                /** @type {TimersMap} */
                (this[TIMERS_SYMBOL]).delete(label);
                this[LOG_SYMBOL](LogType.time, [label, ...time]);
        }

        /**
         * Processes the provided label.
         * @param {string=} label label
         */
        timeAggregate(label) {
                const prev = this[TIMERS_SYMBOL] && this[TIMERS_SYMBOL].get(label);
                if (!prev) {
                        throw new Error(
                                `No such label '${label}' for WebpackLogger.timeAggregate()`
                        );
                }
                const time = process.hrtime(prev);
                /** @type {TimersMap} */
                (this[TIMERS_SYMBOL]).delete(label);
                /** @type {TimersMap} */
                this[TIMERS_AGGREGATES_SYMBOL] =
                        this[TIMERS_AGGREGATES_SYMBOL] || new Map();
                const current = this[TIMERS_AGGREGATES_SYMBOL].get(label);
                if (current !== undefined) {
                        if (time[1] + current[1] > 1e9) {
                                time[0] += current[0] + 1;
                                time[1] = time[1] - 1e9 + current[1];
                        } else {
                                time[0] += current[0];
                                time[1] += current[1];
                        }
                }
                this[TIMERS_AGGREGATES_SYMBOL].set(label, time);
        }

        /**
         * Time aggregate end.
         * @param {string=} label label
         */
        timeAggregateEnd(label) {
                if (this[TIMERS_AGGREGATES_SYMBOL] === undefined) return;
                const time = this[TIMERS_AGGREGATES_SYMBOL].get(label);
                if (time === undefined) return;
                this[TIMERS_AGGREGATES_SYMBOL].delete(label);
                this[LOG_SYMBOL](LogType.time, [label, ...time]);
        }
}

module.exports.Logger = WebpackLogger;