Cron job does NOT get the environment variables set in .bashrc

The reason for source ~/.bashrc not working is the contents on your ~/.bashrc (default one from Ubuntu 12.04). If you look in it you will see on lines 5 and 6 the following:

# If not running interactively, don't do anything[ -z "$PS1" ] && return

PS1 variable is set for an interactive shell, so it's absent when run via cron, even though you are executing it as a login shell. This is confirmed by contents of the file produced by /bin/bash -l -c -x 'source ~/.bashrc; echo $EDITOR > /tmp/cronjob.test':

+ source /home/plee/.bashrc++ '[' -z '' ']'++ return

To make source ~/.bashrc work, comment out the line that checks for presence of the PS1 variable in ~/.bashrc:

#[ -z "$PS1" ] && return

This will make bash execute the entire contents of ~/.bashrc via cron

Answer provided by @alex is correct but in Ubuntu 13.10 the code has been modified a little. There is no $PS1 variable but in lines 6-9 there is a code

case $- in    *i*) ;;          *) return;; esac

Just commenting out the line which returns works. i.e. the code below works

case $- in    *i*) ;;       #   *) return;; esac

I just tried a file .env_setup_rc file with only one line export EDITOR=vim, surprisingly it's working.

So I guess there is something in .bashrc conflicting with the cron job bash command.