log.js

/* eslint-disable */
let indent = 1;
function log(Class) {
    const descriptors = {};

    Reflect.ownKeys(Class.prototype).forEach(key => {
        const descriptor = Reflect.getOwnPropertyDescriptor(Class.prototype, key);
        const {value} = descriptor;

        descriptors[key] = descriptor;
        if (key === 'constructor' || typeof value !== 'function') return;

        const method = `${Class.name}.${key}`;

        descriptor.value = function() {
            const prefix = '|-'.repeat(indent) + method;
            indent++;
            console.debug(prefix, '(', ...arguments, ')');
            const result = value.apply(this, arguments);
            console.debug(prefix, '<', result && result.$$typeof ? result.$$typeof : result);
            indent--;
            return result;
        };
    });

    Class.prototype = Object.create(
        Object.getPrototypeOf(Class.prototype),
        descriptors
    );
}
/* eslint-enable */