主提交然后与另一个分支合并

Question

I've never tried this before. Suppose that you have two branches "master" and "aBranch", you create aBranch then commit master branch which is ahead of aBranch. Always I merge with branch that are ahead of master but not in reverse. What will happen if you merge master (which is ahead) with aBranch when no conflicting files are involved?

Answer 1

It depends on the relationship between master and aBranch . If your history looks something like this:

* (master)
|
*
|
* (aBranch)

then nothing happens, since master can already reach every commit reachable from aBranch .

If, instead, you have something like

* (master)
|
*  * (aBranch)
|  |
*  *
| /
*

then you get just what you would if you tried to merge the other way. The only difference is the order in which the merge commit stores its two parents, and which branch head is advanced.

* (master)
| \
*  |
|  |
*  * (aBranch)
|  |
*  *
| /
*