JSON Patch

Requirements

• Export applyJSONPatch(document, operations) as named and default. document and operation values are acyclic JSON trees: null, booleans, strings, finite numbers, dense arrays, or plain string-keyed objects. Return a deep-cloned updated document. Even an empty patch returns a clone for object/array roots.
• Support only add, remove, and replace operations, processed sequentially. Each has op and path; add/replace must have an own value property. Unknown operations, missing values, non-string paths, and malformed pointers throw TypeError.
• Paths follow the JSON Pointer string form: empty string addresses the root; other paths start with /. Decode ~1 as / and ~0 as ~, in that order. Empty tokens are valid object keys. Do not percent-decode tokens or accept URI-fragment pointers. Reject invalid ~ escapes.
• All parent containers must already exist as own properties or valid array indexes. For objects, add inserts or overwrites a key; remove/replace require an existing own key. For arrays, canonical indexes have no leading zeros. add inserts at indexes 0..length or appends with final -; remove/replace require indexes below length. The - token is an ordinary object key.
• Root add/replace replace the full document with a cloned operation value. Root remove is unsupported and throws Error. Missing parents/targets, invalid array indexes, and traversal through primitive values throw Error. Restrict decoded __proto__, constructor, and prototype tokens with TypeError as a deliberate safety rule beyond the supported RFC subset.
• Never mutate the document, operation objects, or inserted values. If any operation fails, throw and leave all caller inputs unchanged; intermediate work need not be returned. Copy object keys with safe own-property definitions. No move, copy, test, auto-created parents, circular values, or full RFC implementation is required.

Examples

Input: applyJSONPatch({ tags: ["a", "c"], name: "old" }, [{ op: "add", path: "/tags/1", value: "b" }, { op: "replace", path: "/name", value: "new" }]);
Output: { tags: ["a", "b", "c"], name: "new" }

Input: applyJSONPatch({ "a/b": 1 }, [{ op: "remove", path: "/a~1b" }]);
Output: {}