update-go.sh

#!/bin/bash

case $1 in
    -h | --help ) echo "usage: $(basename $0) [VERSION]"; exit;;
esac

if [ $# -gt 1 ]; then
    1>&2 echo "error: wrong number of argument"
    exit 1
fi

cur=$(go version | awk '{print substr($3, 3)}')

if [ -z "$1" ]; then
    # bump patch
    version=$(echo ${cur} | awk -F. '{print $1  "."  $2  "." $3+1}')
else
    version=$1
fi

echo "updating go to version ${version} (current: ${cur})"
go install golang.org/dl/go${version}@latest
go${version} download
echo "updating link"
ln -sfn ${HOME}/sdk/go${version} ${HOME}/sdk/go