Compare View should be created to handle showing diff for multiple commits/branches
Currently in gitg, we mainly have two views, a History View for showing the different commits made on a branch, and a Commit View that shows the files changed on the working directory.
I'm leaning towards making a new "Compare View" instead of cramming everything in the History View as @albfan suggested on the issue for the feature.
Mainly, we need to handle three use cases, in which, users choose two commits on the same branch to compare, users choose two commits from two different branches to compare, or users choose to compare two whole branches. So we need to handle those three use cases, however refactoring the History View to handle them won't be that effective and not a sustainable solutions, so I think it'll be a lot better if I created a new View for the comparison, this has been done in gitlab, and github for example. I also tried playing with different git clients, they either have a separate view for it, or they don't support the whole functionality.