Git: show total file size difference between two commits?

Question

Is it possible to show the total file size difference between two commits? Something like:

$ git file-size-diff 7f3219 bad418 # I wish this worked :)
-1234 b         


        

Answer 1

A comment to the script: git-file-size-diff, suggested by patthoyts. The script is very useful, however, I have found two issues:

1. When someone change permissions on the file, git returns a another type in the case statement:

   T) echo >&2 "Skipping change of type"
   continue ;;
   

2. If a sha-1 value doesn't exist anymore (for some reason), the script crashes. You need to validate the sha before getting the file size:

   $(git cat-file -e $D) if [ "$?" = 1 ]; then continue; fi

The complete case statement will then look like this:

case $M in
      M) $(git cat-file -e $D)
         if [ "$?" = 1 ]; then continue; fi
         $(git cat-file -e $C)
         if [ "$?" = 1 ]; then continue; fi
         bytes=$(( $(git cat-file -s $D) - $(git cat-file -s $C) )) ;;
      A) $(git cat-file -e $D)
         if [ "$?" = 1 ]; then continue; fi
         bytes=$(git cat-file -s $D) ;;
      D) $(git cat-file -e $C)
         if [ "$?" = 1 ]; then continue; fi
         bytes=-$(git cat-file -s $C) ;;
      T) echo >&2 "Skipping change of type"
         continue ;;
      *)
        echo >&2 warning: unhandled mode $M in \"$A $B $C $D $M $P\"
        continue
        ;;
    esac