Ihor Radchenko <yantar92@posteo.net> writes:

> Max Nikulin <manikulin@gmail.com> writes:
>
>>>    [previous object <max(n1,n2) spaces>]
>>
>> Yes, you do.
>>
>> I expected some complications due to newline characters (not line break 
>> markup objects), but they are not included in :post-blank and 
>> represented as "\n" string objects.
>
> Newlines are tricky. They may or may not be significant.
> For example, in CJK paragraphs, newlines are to be stripped.
>
> I think that a reasonable thing to do could be not adding newlines if
> the previous object is a plain string ending with a newline.

I think that using max(n1,n2) is an overkill. There is no reason to
alter existing spaces before, if any.

I am attaching tentative patch that simply keeps spaces, but if and only
if the previous object does not end with whitespace (including newline).