Reviewing git patches with the source file without applying the patch

[husain@alshehhi.io]

Hello,

I often receive patches (files generated by 'git format-path'
command). I review these files in diff-mode. This is in most cases is
enough. But sometimes, I want to see the source code before and after
the change so that I can see the full context. I am not sure how to do
this in emacs.

diff-mode provides C-c C-c (which is diff-goto-source). This is great
improvement, but it shows the source file only, not the changes before
and after. I have to compute in my head the patch against the source
file to undrestand the change. Additionally, diff-goto-source requires
the path to the source file. I wish it would take the dir instead and it
can compute the source file on its own.

diff-mode also provides C-c C-e (which is diff-ediff-patch). This view
is what I am looking for: it provides a view when I can see the source
file before and after the change. However, diff-ediff-patch applies the
change automatically, which is not what I want to do. Additionally,
diff-ediff-patch generates .orig files which are also unwant.

Any help is appreciated.