Macs come with Python (and Idle is included), Ruby, PHP, Perl, BASH, Apache web server, git, Vim, Emacs, Pico, Nano etc and XCode with clang for C/C++/Objective C/Objective C++ is a free download (used to ship on OS DVD but OS is no longer shipped on physical media).

Java used to be bundled too out of the box, but Apple has deprecated their JVM. Of course Oracle has up to date JDK for OS X now.

Really getting compilers and dev tools for Unix OSes is trivially easy. Almost everything is free if not open source.