I am trying to install Indigo on El Captain via home-brew, everything seems to be fine until I try to run turtlesim? Anyone can help here?

Hangs-MBP:turtlesim Hang$ rosrun turtlesim turtlesimnode [rosrun] Couldn't find executable named turtlesimnode below /Users/Hang/roscatkinws/src/ros_tutorials/turtlesim

I also tried rosmake which ran successfully and I also source my setup.sh, but the error remains.