@nuxt/devalue
Version:
Gets the job done when JSON.stringify can't
237 lines (234 loc) • 7.6 kB
JavaScript
const chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_$";
const unsafeChars = /[<>\b\f\n\r\t\0\u2028\u2029]/g;
const reserved = /^(?:do|if|in|for|int|let|new|try|var|byte|case|char|else|enum|goto|long|this|void|with|await|break|catch|class|const|final|float|short|super|throw|while|yield|delete|double|export|import|native|return|switch|throws|typeof|boolean|default|extends|finally|package|private|abstract|continue|debugger|function|volatile|interface|protected|transient|implements|instanceof|synchronized)$/;
const escaped = {
"<": "\\u003C",
">": "\\u003E",
"/": "\\u002F",
"\\": "\\\\",
"\b": "\\b",
"\f": "\\f",
"\n": "\\n",
"\r": "\\r",
" ": "\\t",
"\0": "\\0",
"\u2028": "\\u2028",
"\u2029": "\\u2029"
};
const objectProtoOwnPropertyNames = Object.getOwnPropertyNames(Object.prototype).sort().join("\0");
function devalue(value) {
const counts = /* @__PURE__ */ new Map();
let logNum = 0;
function log(message) {
if (logNum < 100) {
console.warn(message);
logNum += 1;
}
}
function walk(thing) {
if (typeof thing === "function") {
log(`Cannot stringify a function ${thing.name}`);
return;
}
if (counts.has(thing)) {
counts.set(thing, counts.get(thing) + 1);
return;
}
counts.set(thing, 1);
if (!isPrimitive(thing)) {
const type = getType(thing);
switch (type) {
case "Number":
case "String":
case "Boolean":
case "Date":
case "RegExp":
return;
case "Array":
thing.forEach(walk);
break;
case "Set":
case "Map":
Array.from(thing).forEach(walk);
break;
default:
const proto = Object.getPrototypeOf(thing);
if (proto !== Object.prototype && proto !== null && Object.getOwnPropertyNames(proto).sort().join("\0") !== objectProtoOwnPropertyNames) {
if (typeof thing.toJSON !== "function") {
log(`Cannot stringify arbitrary non-POJOs ${thing.constructor.name}`);
}
} else if (Object.getOwnPropertySymbols(thing).length > 0) {
log(`Cannot stringify POJOs with symbolic keys ${Object.getOwnPropertySymbols(thing).map((symbol) => symbol.toString())}`);
} else {
Object.keys(thing).forEach((key) => walk(thing[key]));
}
}
}
}
walk(value);
const names = /* @__PURE__ */ new Map();
Array.from(counts).filter((entry) => entry[1] > 1).sort((a, b) => b[1] - a[1]).forEach((entry, i) => {
names.set(entry[0], getName(i));
});
function stringify(thing) {
if (names.has(thing)) {
return names.get(thing);
}
if (isPrimitive(thing)) {
return stringifyPrimitive(thing);
}
const type = getType(thing);
switch (type) {
case "Number":
case "String":
case "Boolean":
return `Object(${stringify(thing.valueOf())})`;
case "RegExp":
return thing.toString();
case "Date":
return `new Date(${thing.getTime()})`;
case "Array":
const members = thing.map((v, i) => i in thing ? stringify(v) : "");
const tail = thing.length === 0 || thing.length - 1 in thing ? "" : ",";
return `[${members.join(",")}${tail}]`;
case "Set":
case "Map":
return `new ${type}([${Array.from(thing).map(stringify).join(",")}])`;
default:
if (thing.toJSON) {
let json = thing.toJSON();
if (getType(json) === "String") {
try {
json = JSON.parse(json);
} catch (e) {
}
}
return stringify(json);
}
if (Object.getPrototypeOf(thing) === null) {
if (Object.keys(thing).length === 0) {
return "Object.create(null)";
}
return `Object.create(null,{${Object.keys(thing).map((key) => `${safeKey(key)}:{writable:true,enumerable:true,value:${stringify(thing[key])}}`).join(",")}})`;
}
return `{${Object.keys(thing).map((key) => `${safeKey(key)}:${stringify(thing[key])}`).join(",")}}`;
}
}
const str = stringify(value);
if (names.size) {
const params = [];
const statements = [];
const values = [];
names.forEach((name, thing) => {
params.push(name);
if (isPrimitive(thing)) {
values.push(stringifyPrimitive(thing));
return;
}
const type = getType(thing);
switch (type) {
case "Number":
case "String":
case "Boolean":
values.push(`Object(${stringify(thing.valueOf())})`);
break;
case "RegExp":
values.push(thing.toString());
break;
case "Date":
values.push(`new Date(${thing.getTime()})`);
break;
case "Array":
values.push(`Array(${thing.length})`);
thing.forEach((v, i) => {
statements.push(`${name}[${i}]=${stringify(v)}`);
});
break;
case "Set":
values.push("new Set");
statements.push(`${name}.${Array.from(thing).map((v) => `add(${stringify(v)})`).join(".")}`);
break;
case "Map":
values.push("new Map");
statements.push(`${name}.${Array.from(thing).map(([k, v]) => `set(${stringify(k)}, ${stringify(v)})`).join(".")}`);
break;
default:
values.push(Object.getPrototypeOf(thing) === null ? "Object.create(null)" : "{}");
Object.keys(thing).forEach((key) => {
statements.push(`${name}${safeProp(key)}=${stringify(thing[key])}`);
});
}
});
statements.push(`return ${str}`);
return `(function(${params.join(",")}){${statements.join(";")}}(${values.join(",")}))`;
} else {
return str;
}
}
function getName(num) {
let name = "";
do {
name = chars[num % chars.length] + name;
num = ~~(num / chars.length) - 1;
} while (num >= 0);
return reserved.test(name) ? `${name}0` : name;
}
function isPrimitive(thing) {
return Object(thing) !== thing;
}
function stringifyPrimitive(thing) {
if (typeof thing === "string") {
return stringifyString(thing);
}
if (thing === void 0) {
return "void 0";
}
if (thing === 0 && 1 / thing < 0) {
return "-0";
}
const str = String(thing);
if (typeof thing === "number") {
return str.replace(/^(-)?0\./, "$1.");
}
return str;
}
function getType(thing) {
return Object.prototype.toString.call(thing).slice(8, -1);
}
function escapeUnsafeChar(c) {
return escaped[c] || c;
}
function escapeUnsafeChars(str) {
return str.replace(unsafeChars, escapeUnsafeChar);
}
function safeKey(key) {
return /^[_$a-zA-Z][_$a-zA-Z0-9]*$/.test(key) ? key : escapeUnsafeChars(JSON.stringify(key));
}
function safeProp(key) {
return /^[_$a-zA-Z][_$a-zA-Z0-9]*$/.test(key) ? `.${key}` : `[${escapeUnsafeChars(JSON.stringify(key))}]`;
}
function stringifyString(str) {
let result = '"';
for (let i = 0; i < str.length; i += 1) {
const char = str.charAt(i);
const code = char.charCodeAt(0);
if (char === '"') {
result += '\\"';
} else if (char in escaped) {
result += escaped[char];
} else if (code >= 55296 && code <= 57343) {
const next = str.charCodeAt(i + 1);
if (code <= 56319 && (next >= 56320 && next <= 57343)) {
result += char + str[++i];
} else {
result += `\\u${code.toString(16).toUpperCase()}`;
}
} else {
result += char;
}
}
result += '"';
return result;
}
module.exports = devalue;
;