One awk script to format the output of git log to statistics the file change and LoC insertions/deletions

format-git-log.sh

#git log --shortstat --since="1 Jan, 2019" > log.txt

BEGIN {
    commit="";
    date="";
    file=0;
    add=0;
    del=0;

}

{
    if (index($1, "commit")!=0)
        commit=$2;
    if (index($1, "Date:")!=0)
        date=sprintf("%s %s, %s", $3, $4, $6);
    if (index($3, "changed")!=0){
        file=$1;
        if(index($0, "insertions")!=0 && index($0, "deletions")!=0){
            add=$4;
            del=-$6;
        }
        else {
            if(index($0, "insertions")!=0)
              add=$4;
            else
              del=-$4
        }
        printf("%s;%s;%s;%s;%s\n", commit,date,file,add,del);
      file=0;
      add=0;
      del=0;
    }

}