While doing some diagnostic work today to determine changes within a big directory of code across two versions, I wanted to remove the noise to see only the modified files in a git diff. After a quick search around, I found myself in the Git documentation scrolling through command options.
And there I found it, a flag --diff-filter.
To diff some changes but only show modified files, use
git diff --diff-filter=MOr to just remove added and deleted files, to keep changes like rename or unmerged, the lowercase works as an inverted filter; a == !A.
git diff --diff-filter=ad