gcloud with zsh

.zshrc

# The next line updates PATH for the Google Cloud SDK.
source /Users/dwchiang/google-cloud-sdk/path.zsh.inc

# The next line enables zsh completion for gcloud.
source /Users/dwchiang/google-cloud-sdk/completion.zsh.inc

path.zsh.inc

script_link="$( readlink "$0" )" || script_link="$0"
apparent_sdk_dir="${script_link%/*}"
if [ "$apparent_sdk_dir" == "$script_link" ]; then
  apparent_sdk_dir=.
fi
sdk_dir="$( cd -P "$apparent_sdk_dir" && pwd -P )"
bin_path="$sdk_dir/bin"
export PATH=$bin_path:$PATH