src/vs/workbench/contrib/notebook/common/services/notebookSimpleWorker.ts/NotebookEditorSimpleWorker/computeDiff
class NotebookEditorSimpleWorker:	computeDiff(originalUrl: string, modifiedUrl: string): INotebookDiffResult {
		const original = this._getModel(originalUrl);
		const modified = this._getModel(modifiedUrl);

		const diff = new LcsDiff(new CellSequence(original), new CellSequence(modified));
		const diffResult = diff.ComputeDiff(false);

		/* let cellLineChanges: { originalCellhandle: number, modifiedCellhandle: number, lineChanges: editorCommon.ILineChange[] }[] = [];

		diffResult.changes.forEach(change => {
			if (change.modifiedLength === 0) {
				// deletion ...
				return;
			}

			if (change.originalLength === 0) {
				// insertion
				return;
			}

			for (let i = 0, len = Math.min(change.modifiedLength, change.originalLength); i < len; i++) {
				let originalIndex = change.originalStart + i;
				let modifiedIndex = change.modifiedStart + i;

				const originalCell = original.cells[originalIndex];
				const modifiedCell = modified.cells[modifiedIndex];

				if (originalCell.getValue() !== modifiedCell.getValue()) {
					// console.log(`original cell ${originalIndex} content change`);
					const originalLines = originalCell.textBuffer.getLinesContent();
					const modifiedLines = modifiedCell.textBuffer.getLinesContent();
					const diffComputer = new DiffComputer(originalLines, modifiedLines, {
						shouldComputeCharChanges: true,
						shouldPostProcessCharChanges: true,
						shouldIgnoreTrimWhitespace: false,
						shouldMakePrettyDiff: true,
						maxComputationTime: 5000
					});

					const lineChanges = diffComputer.computeDiff().changes;

					cellLineChanges.push({
						originalCellhandle: originalCell.handle,
						modifiedCellhandle: modifiedCell.handle,
						lineChanges
					});

					// console.log(lineDecorations);

				} else {
					// console.log(`original cell ${originalIndex} metadata change`);
				}

			}
		});
 */
		return {
			cellsDiff: diffResult,
			// linesDiff: cellLineChanges
		};
	}