Anyway: suppose you have two text files, A and B, unterminated; that is: without a final EOL.
Let say file A is:
and file B is:Line 1
After comparing them you click on the arrow at the side of "Line 3" to copy it to the other file.Line 1
Now you see them perfectly equal. Good.
The you save file B and... file B ha become as follows:
Beside having something different from what you saw on screen, I think it's logical to automatically add an EOL to "Line 2" befor appending a new line.Line 1
Line 2Line 3
And now there is the conundrum: which EOL? CR? LF? Both?
I leave this to you.