JsonDiff bug found

[fmoghaddam]

Consider the following Jsons:

Source:

{
    "store": {
        "a": [
            "v1",
            "v2"
        ]
    }
}

Target:

{
    "store": {
        "a": []
    }
}

running JsonDiff.asJson(source, target) returns:

[ {
  "op" : "remove",
  "path" : "/store/a/0"
}, {
  "op" : "remove",
  "path" : "/store/a/0"
} ]

which as it is seen both path is same but actually the next path should be "/store/a/1". The reason is there is a bug in JsonDiff class in function generateArrayDiffs. There is a for loop as:

for(index = size; index < firstSize; ++index) {
   processor.valueRemoved(pointer.append(size), source.get(index));
}

Which should be changed to:

for(index = size; index < firstSize; ++index) {
   processor.valueRemoved(pointer.append(index), source.get(index));
}

[ka1amita]

@fmoghaddam IMHO it is technically correct. The patch operations are applied one by one and a new JSON is constructed in betweeen - with array of length 1.

From spec:

If removing an element from an array, any elements above the specified index are shifted one position to the left.

is also valid:

[ 
  {"op" : "remove", "path" : "/store/a/1"}, 
  {"op" : "remove", "path" : "/store/a/0"} 
]

is invalid

[ 
  {"op" : "remove", "path" : "/store/a/0"}, 
  {"op" : "remove", "path" : "/store/a/1"} 
]