I am just wondering if there is a way to simply diff two branches in GitHub? I know GitHub has capacity to do it because when we do code-reviews it does list out all the dif
There is also another way to achieve this on GitHub, Just try to create a new Pull Request with the branches you would like to compare.
For example
branch-1 <- branch-2 or branch-2 <- branch-1
On the bottom, you can see the file and commit difference between those branches. Just don't Create the Pull request if you don't want to merge these two.