src/vs/editor/contrib/caretOperations/moveCaretCommand.ts/MoveCaretCommand/computeCursorState
class MoveCaretCommand:	public computeCursorState(model: ITextModel, helper: ICursorStateComputerData): Selection {
		if (this._isMovingLeft) {
			return new Selection(this._selection.startLineNumber, this._selection.startColumn - 1, this._selection.endLineNumber, this._selection.endColumn - 1);
		} else {
			return new Selection(this._selection.startLineNumber, this._selection.startColumn + 1, this._selection.endLineNumber, this._selection.endColumn + 1);
		}
	}