im-pytest

A thin runner over pytest for the Instructing Machines course. One set of per-project test files is surfaced three escalating ways across the term, so testing grows from a hidden safety net into a tool students wield themselves.

import im_pytest

im_pytest.check("translationproject")   # friendly panel: ✓/✗ per function

The three modes (one artifact)

1. Hidden friendly runner — check("translationproject") or the %%test cell magic. Runs the project's bundled tests against the student's translationproject.py and renders a beginner-friendly panel: a green ✓ or red ✗ per function, the failing assertion, and a "functions not defined yet" note. No test source, no traceback. For the early weeks, before students know what a test is.
2. Raw pytest — pytest test_translationproject.py. The same file, now run with the real tool so students learn to read pytest's output. The module fixture, the requires marker and the not-defined banner are provided automatically (this package registers a pytest11 plugin).
3. Student-authored — students write their own assert-based tests to specify and validate AI-produced code, using the provided files as the model.

There is also a terminal entry point:

pytest-check translationproject.py      # or: pytest-check translationproject

Writing a project test file

Per-project test files are plain, idiomatic pytest. They receive module (the student's solution module, imported fresh with the student's own print output suppressed) and mark each test with requires so an unwritten function is reported as "not defined" instead of crashing:

from im_pytest import requires

@requires.translate_codon
def test_translate_codon(module):
    assert module.translate_codon("ATG") == "M"
    assert module.translate_codon("NNN") == "?"     # invalid codon
    assert module.translate_codon("atg") == "M"     # lowercase

@requires.translate_codon is sugar for @pytest.mark.requires("translate_codon") (and stacks equivalently if two are put on the same test); for several names at once use the call form, @requires("translate_codon", "split_codons").

module resolves to <project>.py in the working folder (its name is the test file name minus its test_ prefix). Project test files and their data live in the course repository and are distributed to students as downloads; set IM_PROJECT_TESTS to point the runner at a shared folder instead of the working directory.

Dict/set equality ignores order, so a plain == can't catch a correctly-valued but wrongly-ordered result. ordered(value) sorts by type — a dict by its values, a list/tuple in place (same type back), anything else iterable via sorted() — so an order-sensitive check is one line:

from im_pytest import ordered

@requires.codon_bias
def test_codon_bias(module):
    assert list(module.codon_bias(seq).items()) == list(ordered(expected).items())

Development

pixi run install-dev
pixi run test

License

MIT