Testing

JANUS uses pytest for its test suite. The tests verify physical correctness by comparing model output against known reference values, and check utility functions and constants.

Prerequisites

Install the test dependencies:

pip install pytest
pip install -r examples/requirements.txt

Make sure RAD_DIR and FWL_DATA are set before running:

echo $RAD_DIR    # should point to your SOCRATES installation
echo $FWL_DATA   # should point to your data directory

Running the tests

From the root of the JANUS repository:

pytest tests/

To run a specific test file:

pytest tests/test_runaway_greenhouse.py
pytest tests/test_instellation.py
pytest tests/test_constants.py
pytest tests/test_code.py

To run with verbose output:

pytest tests/ -v

What the tests check

test_runaway_greenhouse.py

Runs the full JANUS pipeline at three surface temperatures for a pure H₂O atmosphere at 0.3 AU and checks the OLR against reference values to a relative tolerance of 1 × 10⁻⁵:

Uses RadConvEqm() with cp_dry=False, trppD=False, rscatter=False.

test_instellation.py

Runs MCPA_CBL() — the coupled boundary layer solver — at two orbital distances (0.3 AU and 1.4 AU) using config_instellation.toml and checks five output quantities against reference values:

(SW_flux_down[0], LW_flux_up[0], net_flux[0], ts, trppT)

Unlike the runaway greenhouse test this uses rscatter=True and setTropopauseTemperature() (dynamic skin-temperature tropopause).

test_constants.py

Checks physical constants and utility functions:

• gravity() decreases with radius as expected
• Earth planet constants match database values (g = 9.798, albedo = 0.306, Tsbar = 288.0)
• cpv() returns finite, positive heat capacities for H₂O, CO₂, N₂, H₂, CH₄, O₂

test_code.py

Checks utility code and the CLI:

• setup_logger() sets the correct log level and handler count; raises ValueError for invalid levels
• natural_sort() correctly sorts filenames with embedded numbers
• janus env CLI command exits successfully and prints RAD_DIR