Show conflict diff part of a merge
If you use the standard gitk tool, and click on a merge commit, the lower left pane shows the conflict resolutions.
Just use
git diff ORIG_HEAD MERGE_HEAD(or FETCH_HEAD)
MERGE_HEAD holds for your local merged files, ORIG_HEAD is the commit possible conflicting that you want to merge.
FETCH_HEAD is the hash for the repo you fetch changes before merging.
As said above, PULL only does fetch (in the remote repo, possible origin) and a Merge
In case of doubt see your .git folder to see the files where hashes are being stored.
Look at the hash (or tag) of the merge commit (the commit that has multiple parents) and do:
git diff hash hash^1 hash^2
It will output a 3 way-diff of the changes.
hash^ (or hash^1) references the first parent commit of hashhash^2 references the second parent commit of hash