index.js•3.74 kB
'use strict'
const hasBuffer = typeof Buffer !== 'undefined'
const suspectProtoRx = /"(?:_|\\u005[Ff])(?:_|\\u005[Ff])(?:p|\\u0070)(?:r|\\u0072)(?:o|\\u006[Ff])(?:t|\\u0074)(?:o|\\u006[Ff])(?:_|\\u005[Ff])(?:_|\\u005[Ff])"\s*:/
const suspectConstructorRx = /"(?:c|\\u0063)(?:o|\\u006[Ff])(?:n|\\u006[Ee])(?:s|\\u0073)(?:t|\\u0074)(?:r|\\u0072)(?:u|\\u0075)(?:c|\\u0063)(?:t|\\u0074)(?:o|\\u006[Ff])(?:r|\\u0072)"\s*:/
function _parse (text, reviver, options) {
// Normalize arguments
if (options == null) {
if (reviver !== null && typeof reviver === 'object') {
options = reviver
reviver = undefined
}
}
if (hasBuffer && Buffer.isBuffer(text)) {
text = text.toString()
}
// BOM checker
if (text && text.charCodeAt(0) === 0xFEFF) {
text = text.slice(1)
}
// Parse normally, allowing exceptions
const obj = JSON.parse(text, reviver)
// Ignore null and non-objects
if (obj === null || typeof obj !== 'object') {
return obj
}
const protoAction = (options && options.protoAction) || 'error'
const constructorAction = (options && options.constructorAction) || 'error'
// options: 'error' (default) / 'remove' / 'ignore'
if (protoAction === 'ignore' && constructorAction === 'ignore') {
return obj
}
if (protoAction !== 'ignore' && constructorAction !== 'ignore') {
if (suspectProtoRx.test(text) === false && suspectConstructorRx.test(text) === false) {
return obj
}
} else if (protoAction !== 'ignore' && constructorAction === 'ignore') {
if (suspectProtoRx.test(text) === false) {
return obj
}
} else {
if (suspectConstructorRx.test(text) === false) {
return obj
}
}
// Scan result for proto keys
return filter(obj, { protoAction, constructorAction, safe: options && options.safe })
}
function filter (obj, { protoAction = 'error', constructorAction = 'error', safe } = {}) {
let next = [obj]
while (next.length) {
const nodes = next
next = []
for (const node of nodes) {
if (protoAction !== 'ignore' && Object.prototype.hasOwnProperty.call(node, '__proto__')) { // Avoid calling node.hasOwnProperty directly
if (safe === true) {
return null
} else if (protoAction === 'error') {
throw new SyntaxError('Object contains forbidden prototype property')
}
delete node.__proto__ // eslint-disable-line no-proto
}
if (constructorAction !== 'ignore' &&
Object.prototype.hasOwnProperty.call(node, 'constructor') &&
Object.prototype.hasOwnProperty.call(node.constructor, 'prototype')) { // Avoid calling node.hasOwnProperty directly
if (safe === true) {
return null
} else if (constructorAction === 'error') {
throw new SyntaxError('Object contains forbidden prototype property')
}
delete node.constructor
}
for (const key in node) {
const value = node[key]
if (value && typeof value === 'object') {
next.push(value)
}
}
}
}
return obj
}
function parse (text, reviver, options) {
const stackTraceLimit = Error.stackTraceLimit
Error.stackTraceLimit = 0
try {
return _parse(text, reviver, options)
} finally {
Error.stackTraceLimit = stackTraceLimit
}
}
function safeParse (text, reviver) {
const stackTraceLimit = Error.stackTraceLimit
Error.stackTraceLimit = 0
try {
return _parse(text, reviver, { safe: true })
} catch (_e) {
return null
} finally {
Error.stackTraceLimit = stackTraceLimit
}
}
module.exports = parse
module.exports.default = parse
module.exports.parse = parse
module.exports.safeParse = safeParse
module.exports.scan = filter