Get all commits; for each commit show a sequence number of a commit after the last tag

tag-num-commits.sh

#!/bin/bash
# the last tag
tag=$(git tag | head -1)

# number of commits after tag
c=$(git rev-list $tag..HEAD | wc -l)
c=$((c-0))

# header
printf '%-6s' "TAG" && printf '%-4s' "NUM" && printf "COMMIT\n"

# list of tags, number of commit after tag and a commit hash
git rev-list $tag..HEAD | \
while read line; do \
  printf '%-6s' "$tag" && printf '%-4s' "$c" && printf "$line\n"
  c=$((c-1))
done