How to “git show” a merge commit with combined diff output even when every changed file agrees with one of the parents?

Question

After doing a \"simple\" merge (one without conflicts), git show usually only shows something like

commit 0e1329e551a5700614a2a34d8101e92fd9f2ca         


        

Answer 1

I built a general-purpose approach to doing various operations on a merge's commits.

Step One: Add an alias to git by editing ~/.gitconfig:

[alias]
  range = "!. ~/.githelpers && run_on_merge_range"

Step Two: In ~/.githelpers, define a bash function:

run_on_merge_range() {
  cmd=$1; shift
  commit=$1; shift
  range=$(git show $commit | grep Merge: | awk '{print $2 "..." $3}')
  echo "git $cmd $range $@"
  if [ -z $range ]; then
    echo "No merge detected"
    exit 1
  fi
  git $cmd $range $@
}

Step Three: Profit!

git range log  --oneline
git range diff  --reverse -p
git range diff  --name-only

There is probably a LOT of room for improvement here, I just whipped this together to get past an annoying situation. Feel free to mock my bash syntax and/or logic.