I use SourceTree. I have created a branch B from branch A.
Then I made 3 commits to branch B, checked out the branch A and saw someone committed something there.
After that I merged my branch B to branch A. But instead of "merge", I saw my commits duplicated on branch A!
The code of branch A is actually what I wanted it to be, but I didn't want it to duplicate my commits, I just wanted to see how my branch B nicely merges into branch A.
Here is a screenshot of SourceTree log. As you can see four red arrows and four green arrows point to duplicated commits I was talking about:
Why did it duplicate instead of merging? Thank you.