Deleting Array elements

[MrMojoRisin49]

Not sure but I think I've run into an issue dealing with deleting array elements. For example:

oldArray: [thing1, thing2, thing3, thing4]
newArray: [thing1, thing2]

I apply the diff using this code:

diff.observableDiff(oldArray, newArray, function (d) {
diff.applyChange(oldArray, newArray, d);
});

And I expect:

oldArray: [thing1, thing2]

But I get:

oldArray: [thing1, thing2, thing4]

Not sure why this is. Is this an issue with my code or yours. Any help is greatly appreciated. Thanks in advance.

[jonathan-reisdorf]

Same issue here. I guess if you just loop through the diff and apply the changes one by one, the former index 3 will be index 2 after the deletion of thing3. The next applyChange then triggers a delete on thing4, which is recorded to be index 3, but now there is no index 3, so nothing happens.

[jonathan-reisdorf]

For a workaround see here:
#35

[ilovett]

I am also seeing this issue where the index seems to be changed and the diff index is no longer accurate... The workaround mentioned by @jonathan-reisdorf in #35 is to call reverse() on your array of changes...

deep.diff(lhs, rhs).reverse().forEach(function(diffItem) {
  deep.applyChange(lhs, true, diffItem);
});

The default behaviour of deep-diff should be to provide the diffs of arrays already reversed, going from highest index to lowest.

[postrational]

+1 Same issue. Can the observableDiff function be changed to apply changes in reversed order in the library?