Add tests

[Smit-create]

No description provided.

[namannimmo10]

Thanks! Just curious: once #41 is merged, do we really need lpython_tests.py?
We could add tests as separate units in different files and run the whole test suite with ctest.

[Thirumalai-Shaktivel]

do we really need lpython_tests.py?

Nope, as you said we can add separate tests (in separate files) for each implementation.
Then, we execute
./run_tests.py to check whether all the test passes.
./run_tests.py -u to update the tests.

[Smit-create]

Okay, then let's wait for #41 to merge.

[certik]

From now on, let's simply add new files into tests/ and add them into tests/tests.toml.

[certik]

@Smit-create, I added hints which files you can put those tests in. Then register them in tests/tests.toml and then do ./run_tests.py -u, which will generate the reference results in tests/reference/*, simply add them to git and create a PR.

[certik]

This looks good to me. +1 to merge if tests pass.