fix(frontend): handle multi-item array updates in updateYTypeFromObject

[carloea2]

What changes were proposed in this PR?

This PR fixes the pending TODO from Array branch in updateYTypeFromObject(...).

texera/frontend/src/app/workspace/types/shared-editing.interface.ts

Lines 130 to 164 in ac909a0

	} else if (newObjType === "Array") {
	// TODO: Fix this
	const oldYObjAsYArray = oldYObj as unknown as Y.Array<any>;
	const newObjAsArr = newObj as any[];
	const newArrLen = newObjAsArr.length;
	const oldObjAsArr = oldYObjAsYArray.toJSON();
	const oldArrLen = oldObjAsArr.length;
	// TODO: in-place update, assuming only one update at a time can happen.
	if (newArrLen < oldArrLen) {
	let i = 0;
	for (i; i < newArrLen; i++) {
	if (!_.isEqual(oldObjAsArr[i], newObjAsArr[i])) break;
	}
	oldYObjAsYArray.delete(i);
	} else if (newArrLen > oldArrLen) {
	let i = 0;
	for (i; i < newArrLen; i++) {
	if (!_.isEqual(oldObjAsArr[i], newObjAsArr[i])) break;
	}
	oldYObjAsYArray.insert(i, [createYTypeFromObject(newObjAsArr[i])]);
	} else {
	for (let i = 0; i < newArrLen; i++) {
	if (!_.isEqual(oldObjAsArr[i], newObjAsArr[i])) {
	if (!updateYTypeFromObject(oldYObjAsYArray.get(i), newObjAsArr[i])) {
	if (newObjAsArr[i] !== undefined) {
	oldYObjAsYArray.delete(i, 1);
	const res = createYTypeFromObject(newObjAsArr[i]);
	if (res === undefined) oldYObjAsYArray.insert(i, [null]);
	else oldYObjAsYArray.insert(i, [res]);
	}
	}
	}
	}
	}
	} else if (newObjType === "Object") {

Previously, the implementation assumed only one array update happened at a time and only handled the first mismatch with a single insert or delete. This caused incorrect behavior for multi-item insertions, multi-item deletions, and reorder cases.

This PR replaces that logic with an Longest Common Subsequence based array diff so the final Y.Array matches the target array more reliably while still attempting in-place updates where possible.

Any related issues, documentation, discussions?

Closes #4264

How was this PR tested?

Manually tested using:

[1, 2, 3, 4, 5] -> [1, 5]
[1, 2, 3, 4, 5] -> [7, 5, 8, 1 6]
[1, 2] -> [1, 3, 4, 2]
["x", "y", "z"] -> ["z", "x", "y"]

Verified that the final Y.Array content matches the target array.

Was this PR authored or co-authored using generative AI tooling?

Co-generated with GPT

[carloea2]

@chenlica @Xiao-zhen-Liu
The required PR before UiParameter PR.

Thanks

[carloea2]

The new version has O(oldArrLen * newArrLen) time and space complexity, compared with the previous linear O(newArrLen) behavior.

[chenlica]

@Xiao-zhen-Liu Please review it.