git-completion-and-prompt.sh

#!/bin/bash
set -o errexit

# This script gives you git bash completion and a minimal
# prompt displaying the branch name.

PROFILE=""
if [ -f "$HOME/.bashrc" ]; then
  PROFILE="$HOME/.bashrc"
elif [ -f "$HOME/.bash_profile" ]; then
  PROFILE="$HOME/.bash_profile"
fi

if [ ! -f "$PROFILE" ]; then
  echo >&2 "Unable to find ~/.bashrc or ~/.bash_profile"
  exit 1
fi

COMPLETION_DIR=$HOME/opt/git/contrib/completion

if ! grep --quiet "git-completion.bash" $PROFILE; then

  # Download the contrib scripts
  mkdir -p $COMPLETION_DIR
  pushd $COMPLETION_DIR
  curl --silent --show-error --remote-name https://raw.githubusercontent.com/git/git/master/contrib/completion/git-completion.bash
  curl --silent --show-error --remote-name https://raw.githubusercontent.com/git/git/master/contrib/completion/git-prompt.sh
  popd

  echo >> $PROFILE
  echo "# Set git autocompletion and PS1 integration" >> $PROFILE
  echo ". $COMPLETION_DIR/git-completion.bash" >> $PROFILE
  echo ". $COMPLETION_DIR/git-prompt.sh" >> $PROFILE
  echo 'export PS1='"'"'\h:\W$(__git_ps1)\$ '"'" >> $PROFILE

fi