Dumps a TypeScript-like JSON interface of runtime JavaScript objects.

js-runtime-json-interface.js

; (function (targetObj) {
    const STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/gm
    const ARGUMENT_NAMES = /([^\s,]+)/g
    const getParamNames = func => {
        var fnStr = func.toString().replace(STRIP_COMMENTS, '')
        var result = fnStr.slice(fnStr.indexOf('(') + 1, fnStr.indexOf(')')).match(ARGUMENT_NAMES)
        if (result === null) result = []
        return result
    }

    const isClassName = str => str.length > 0 ? str[0] === str[0].toUpperCase() : false
    const isPrivateName = str => str.length <= 2

    const constructorType = func => `(${getParamNames(func).join(', ')}) => any`

    const jsonFunctionType = (name, func) => {
        const interfaceObj = {}

        // Constructor
        if (typeof name === 'string' && isClassName(name)) {
            interfaceObj['new'] = constructorType(func)
        }

        // Statics
        const keys = Object.keys(func)
        const statics = keys.reduce((obj, k) => {
            if (isPrivateName(k)) return obj
            return { ...obj, [k]: func[k] }
        }, {})
        Object.assign(interfaceObj, statics)

        // Prototype methods
        if (func.prototype) {
            const { prototype } = func
            const protoKeys = Object.keys(prototype)
            const methods = protoKeys.reduce((obj, k) => {
                if (k === 'constructor') return obj
                if (isPrivateName(k)) return obj
                return { ...obj, [k]: prototype[k] }
            }, {})
            Object.assign(interfaceObj, methods)
        }

        // Simple function
        if (Object.keys(interfaceObj).length === 0) {
            return constructorType(func)
        }

        return interfaceObj
    }

    const cache = new WeakSet()
    const replacer = (key, value) => {
        const isObj = typeof value === 'object' && value !== null

        // Circular check
        if (isObj && cache.has(value)) {
            return '[Circular]'
        }

        if (key.length && isPrivateName(key)) return
        if (typeof value === 'function') {
            return jsonFunctionType(key, value)
        }

        if (isObj) {
            cache.add(value)
        }
        
        return value
    }

    const json = JSON.stringify(targetObj, replacer, '  ')
    console.log(json)

    if (typeof window.copy === 'function') {
        window.copy(json)
    }
})(cast.framework)