This happens to me all the time when merging, and I'm really not sure why (I saw several answers detailing several possible causes) but the cause is not relevant for my question, because regardless of what causes "tree conflicts" on identical files in identical paths the result is always the same: nothing at all needs to be changed and the "conflict" can just be marked as resolved.
So every time I have a "tree conflict" I have to [checkout the source file if it's not already there,] use a diff tool like WinDiff (because being that a "tree conflict" no SVN client opens its diff tool, although both files are there), compare the two files to find out whether they are identical (they almost always are) and if yes just mark the conflict as resolved without making absolutely any change to "solve" the conflict.
Obviously this is very very time-wasting and it feels really frustrating and pointless.
So I'm wondering if there is any way - through some SVN switch or some SVN client or anything else - to make so that tree conflicts won't be flagged in cases where it's 100% sure that nothing at all needs to be changed in order to solve the conflict - like in the case of my example above.
ADDED: It would also be interesting for me to know how usual it is for people to get tree conflicts on identical files (BTW I'm talking about files that nobody has touched since I created my branch, neither deleted nor recreated nor modified nor moved nor anything else). So you are welcome to leave a comment if you experienced that.
I am not sure why you were down voted, but your question does lack detail and substance. You just kind of say "what" you do but do not really provide any details that could help someone answer the "why". What you ultimately need to figure out is why you are getting the tree conflict in the first place and the only way someone can help you is if you provide details.
I would encourage you to read this section of the SVN book so that you understand why and when SVN flags a tree conflict. I would also use the command line tools that are shown in the book to explore the details of the tree conflict. Hopefully once you understand why you are getting the tree conflict you might know how to avoid it.