make own JSON.stringify

myJSON_stringify.js

// JSON.stringify를 구현하시오
// https://www.youtube.com/watch?v=rQOpmgo99BQ

/**
 * 자료
 * https://reference.codeproject.com/Book/javascript/reference/global_objects/json/stringify
 * https://developer.mozilla.org/ko/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify
 */

const parsingRouter = {
	'string': (v) => `"${v.toString()}"`,
	'number': (v) => v.toString(),
	'null': () => 'null',
	'undefined': (_, valueOwnerConstructor) => valueOwnerConstructor === Array ? 'null' : undefined,
	'function': (_) => 'null',
	'symbol': (_, valueOwnerConstructor) => valueOwnerConstructor === Array ? 'null' : undefined,
	'boolean': (v) => v.toString(),
	'array': (arr, valueOwnerConstructor) => {
		const accumulator = [];
		const func = (item, valueOwnerConstructor) => {
			const arr = [];
			const v = myJSON.valueToString(item, valueOwnerConstructor);
			if (v) {
				arr.push(`${v}`);
			}
			return arr;
		}

		for (let item of arr) {
			let node = item;
			if (myJSON.getType(node) === 'array') {
				let i = 0;
				while (i < node.length) {
					accumulator.push(func(node, node.constructor));
					node = node[i];
					i++;
				}
			} else {
				accumulator.push(func(item, valueOwnerConstructor))
			}
		}

		return myJSON.wrapStr('[', ']', accumulator);
	},
	'object': (obj, valueOwnerConstructor) => {
		const accumulator = [];
		for (let key in obj) {
			const v = myJSON.valueToString(obj[key], valueOwnerConstructor);
			if (v) {
				accumulator.push(`"${key}":${v}`);
			}
		}
		return myJSON.wrapStr('{', '}', accumulator);
	},
};

const valueRouter = {
	'null': () => 'null',
	'undefined': () => undefined,
	'object': (v, valueOwnerConstructor) => myJSON.valueToString(v, valueOwnerConstructor),
	'array': (v, valueOwnerConstructor) => myJSON.valueToString(v, valueOwnerConstructor),
	'boolean': (v) => myJSON.valueToString(v, null),
	'symbol': (v) => myJSON.valueToString(v, null),
	'function': (v) => myJSON.valueToString(v, null),
	'number': (v) => myJSON.valueToString(v, null),
	'string': (v) => myJSON.valueToString(v, null),
}

class myJSON {
	constructor() {

	}

	static getType(value) {
		if (value === null) {
			return ('null');
		} else if (value === undefined) {
			return ('undefined');
		} else {
			let type = typeof value;

			return (type === 'object'
				? Array.isArray(value)
					? 'array'
					: 'object'
				: type);
		}
	}

	static valueToString(value, valueOwnerConstructor) {
		const valueType = myJSON.getType(value);
		let str = parsingRouter[valueType](value, valueOwnerConstructor);

		return str;
	}
	static wrapStr(start, end, str) {
		return `${start}${str.join(',')}${end}`;
	}

	static stringify(value) {
		const valueType = myJSON.getType(value);
		return valueRouter[valueType](value, value ? value.constructor : null);
	}
}

const test01 = {
	str: 'a',
	num: 1,
	'undefined': undefined,
	'null': null,
	symbol: Symbol('test'),
	boolean: true,
}

const tests = [];
tests.push({})
tests.push(1)
tests.push(null)
tests.push('foo')
tests.push([1, '1', true, null, undefined, Symbol(''), () => ''])
tests.push([])
tests.push([1, 2, ["a", [1, 2], false], 3, ["b", "c", [1, 2]]])

function testMyJSON(v) {
	try {
		console.log(`==== real value ====`);
		console.log(v)
		console.log(`==== myJSON() ====`)
		console.log(myJSON.stringify(v))
		console.log(`==== JSON() ====`)
		console.log(JSON.stringify(v))
		console.log("\n\n")
	} catch (e) {
		console.error(e)
	}

}

tests.map(test => testMyJSON(test))