Show current git branch name in Bash prompt

.bashrc

# Function that prints the branch name.
git_branch() {
	branch=`git branch 2> /dev/null | sed -e '/^[^*]/d' | perl -pe 's/^\*\s+//g'`
	if [ "$branch" != '' ]; then
		echo -n " ($branch)"
	fi
}

# Integrate it into your $PS1 prompt.
# Would look like: [user@localhost myapp (master)]$
export PS1="[\u@\h \W\$(git_branch)]\$ "