JSON8 Merge Patch To Patch

Turn JSON Merge Patch into JSON Patch.

JSON Patch is a more capable alternative to JSON Merge Patch.
To work with JSON Patch see JSON8 Patch.

---

npm install json8-merge-patch-to-patch

---

``javascript
const mergePatchToPatch = require("json8-merge-patch-to-patch");
`

Does not validate the merge patch nor the patch for JSON correctness, use JSON8 valid.

---

`javascript
const JSONMergePatch = {
foo: { bar: "foobar" },
bar: null,
};
const JSONPatch = mergePatchToPatch(JSONMergePatch);
/*
[
{ op: 'add', path: '/foo/bar', value: 'foobar' },
{ op: 'remove', path: '/bar' }
]
*/
`

Per specification a JSON Merge Patch that would successfully apply on a document might fail to apply once converted to a JSON Patch.

There are 3 cases:

Incompatible destination

`javascript
const doc = [];
const JSONMergePatch = { a: "hello" };
const JSONPatch = mergePatchToPatch(JSONMergePatch);
// JSONPatch will fail to apply because doc is not an object
`

Wrong location

`javascript
const doc = {};
const JSONMergePatch = { a: { b: "hello" } };
const JSONPatch = mergePatchToPatch(JSONMergePatch);
// JSONPatch will fail to apply because doc.a doesn't exist
`

Remove non-existant value

`javascript
const doc = {};
const JSONMergePatch = { a: null };
const JSONPatch = mergePatchToPatch(JSONMergePatch);
// JSONPatch will fail to apply because doc.a doesn't exist
``

An option could be added to produce a successful JSON Patch no matter what but the only way to do this is to pass the document as well. Let me know if there is any interest or contribute.

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