Set your current directory at a position where you could run
java miniJava.Compiler <inputfile>
Clone this directory, and then run ephemeral-137/tester.sh
through bash.
i.e.
git clone https://github.com/RuneBlaze/ephemeral-137
chmod +x ephemeral-137/tester.sh
./ephemeral-137/tester.sh
which would run the test suite