How to use the levn.parse function in levn

function parseJsonConfig(string, location) {
    let items = {};

    // Parses a JSON-like comment by the same way as parsing CLI option.
    try {
        items = levn.parse("Object", string) || {};

        // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
        // Also, commaless notations have invalid severity:
        //     "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
        // Should ignore that case as well.
        if (ConfigOps.isEverySeverityValid(items)) {
            return {
                success: true,
                config: items
            };
        }
    } catch (ex) {

        // ignore to parse the string by a fallback.
    }

function parseJsonConfig(string, location) {
    let items = {};

    // Parses a JSON-like comment by the same way as parsing CLI option.
    try {
        items = levn.parse("Object", string) || {};

        // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
        // Also, commaless notations have invalid severity:
        //     "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
        // Should ignore that case as well.
        if (ConfigOps.isEverySeverityValid(items)) {
            return {
                success: true,
                config: items
            };
        }
    } catch (ex) {

        // ignore to parse the string by a fallback.
    }

parseJsonConfig(string, location) {
        debug("Parsing JSON config");

        let items = {};

        // Parses a JSON-like comment by the same way as parsing CLI option.
        try {
            items = levn.parse("Object", string) || {};

            // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
            // Also, commaless notations have invalid severity:
            //     "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
            // Should ignore that case as well.
            if (ConfigOps.isEverySeverityValid(items)) {
                return {
                    success: true,
                    config: items
                };
            }
        } catch (ex) {

            debug("Levn parsing failed; falling back to manual parsing.");

            // ignore to parse the string by a fallback.

function parseJsonConfig(string, location, messages) {
    let items = {};

    // Parses a JSON-like comment by the same way as parsing CLI option.
    try {
        items = levn.parse("Object", string) || {};

        // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
        // Also, commaless notations have invalid severity:
        //     "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
        // Should ignore that case as well.
        if (ConfigOps.isEverySeverityValid(items)) {
            return items;
        }
    } catch (ex) {

        // ignore to parse the string by a fallback.
    }

    // Optionator cannot parse commaless notations.
    // But we are supporting that. So this is a fallback for that.
    items = {};

function parseJsonConfig(string, location) {
    let items = {};

    // Parses a JSON-like comment by the same way as parsing CLI option.
    try {
        items = levn.parse("Object", string) || {};

        // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
        // Also, commaless notations have invalid severity:
        //     "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
        // Should ignore that case as well.
        if (ConfigOps.isEverySeverityValid(items)) {
            return {
                success: true,
                config: items
            };
        }
    } catch (ex) {

        // ignore to parse the string by a fallback.
    }