git tricks

# commits per conributor 
git shortlog -s -n

# lines change per conributor
git log --author="<conributor_name>" --pretty=tformat: --numstat | gawk '{ add += $1; subs += $2; loc += $1 - $2 } END { printf "added lines: %s removed lines: %s total lines: %s\n", add, subs, loc }' -

# get repo lines count
git ls-files | xargs cat | wc -l

# git add to local ignore
git update-index --assume-unchanged [<file>...]

# change author of all commits
git filter-branch --commit-filter 'if [ "$GIT_AUTHOR_NAME" = "Josh Lee" ];
  then export GIT_AUTHOR_NAME="Hobo Bob"; export GIT_AUTHOR_EMAIL=hobo@example.com;
  fi; git commit-tree "$@"'
  
# display parent branch
current_branch=$(git rev-parse --abbrev-ref HEAD | sed 's/\//\\\//'); git show-branch | awk -F'[]^~[]' '/\*/ && !/'"$current_branch"'/ {print $2;exit}'

# remove merged branches
git branch --merged | egrep -v "(^\*|master|develop)" | xargs git branch -d


# pretty log
git log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit --branches