caohanyang / json_diff_rfc6902 Goto Github PK

const { diff } = require('json-diff-rfc6902');

const before = {
    a: 'text',
}
const after = {
    a: 'text',
    b: undefined
};

diff(before, after);

crashes with

.\node_modules\json-diff-rfc6902\lib\unchangedArea.js:71
    if (newValue.toString() === value) {
                ^

TypeError: Cannot read property 'toString' of undefined
    at Object.findValueInUnchanged (.\node_modules\json-diff-rfc6902\lib\unchangedArea.js:71:17)
    at generateObjectDiff (.\node_modules\json-diff-rfc6902\JSON-Diff.js:127:35)
    at generateDiff (.\node_modules\json-diff-rfc6902\JSON-Diff.js:51:5)
    at diff (.\node_modules\json-diff-rfc6902\JSON-Diff.js:33:3)

By my opinion, this lib could easily be the most complete json diff/patch library, if the published algorithm is correct this lib is based on.

How to reproduce:
var obj = [ "thisisbad", { choices: [ { choices: [] } ] } ]; jdr.apply(obj, [{ op: "move", from: "/0", path: "/0/choices/0/choices/0" }]);

Result: Uncaught TypeError: Cannot read property '0' of undefined

Expected result:
[ { "choices": [ { "choices": [ "thisisbad" ] } ] } ]

Hi,
first let me thank you for this one, it generates the most clever diffs among all the similar libs i checked. As an extra, it is able to apply patches.
Please consider to implement a "public" get(object, path) method that calculates JSON Pointer, so this lib will cover all basic features people need when working with JSON patches.

In the simple example, a weird "copy" patch is calculated as a diff what is wrong. Check it on codepen or here:

var a = {
  choices: [
    {id: "2"}
  ]
};
var b = {
  choices: [
    {id: "2"}
  ],
  description: "2"
};

var diff = jdr.diff(a, b);
jdr.apply(a, diff, {OBJ_COM:false});

console.info("diff:", diff); // results [{op: "copy", path: "/description", from: "/choices/0"}]
console.info("this should be b:", a); // results something else than b