From e8b46483b3412837997b05f36de4ad5f421c7481 Mon Sep 17 00:00:00 2001
From: Samuel Brand <sam055@mac.com>
Date: Tue, 11 Feb 2025 12:16:29 +0000
Subject: [PATCH] unit tests

---
 tests/test_sbc.py | 71 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 tests/test_sbc.py

diff --git a/tests/test_sbc.py b/tests/test_sbc.py
new file mode 100644
index 0000000..5bdc2dd
--- /dev/null
+++ b/tests/test_sbc.py
@@ -0,0 +1,71 @@
+import numpyro
+import pytest
+from jax import random
+from numpyro.infer import NUTS
+
+from forecasttools.sbc import SBC
+
+
+@pytest.fixture
+def simple_model():
+    def model(y=None):
+        mu = numpyro.sample('mu', numpyro.distributions.Normal(0, 1))
+        numpyro.sample('z', numpyro.distributions.Normal(mu, 1), obs=y)
+    return model
+
+@pytest.fixture
+def mcmc_kernel(simple_model):
+    return NUTS(simple_model)
+
+@pytest.fixture
+def observed_vars():
+    return {"y" : "z"}
+
+@pytest.fixture
+def sbc_instance(mcmc_kernel, observed_vars):
+    return SBC(mcmc_kernel, y = None, observed_vars=observed_vars)
+
+def test_sbc_initialization(sbc_instance, mcmc_kernel, observed_vars):
+    """
+    Test that the SBC class is initialized correctly.
+    """
+    assert sbc_instance.mcmc_kernel == mcmc_kernel
+    assert sbc_instance.observed_vars == observed_vars
+    assert sbc_instance.num_simulations == 10
+    assert sbc_instance.sample_kwargs == dict(num_warmup=500, num_samples=100, progress_bar=False)
+    assert sbc_instance._simulations_complete == 0
+
+def test_get_prior_predictive_samples(sbc_instance):
+    """
+    Test that the prior and prior predictive samples are generated correctly.
+    """
+    prior, prior_pred = sbc_instance._get_prior_predictive_samples()
+    assert "y" in prior_pred
+    assert "mu" in prior
+
+def test_get_posterior_samples(sbc_instance):
+    """
+    Test that the posterior samples are generated correctly.
+    """
+    prior, prior_pred = sbc_instance._get_prior_predictive_samples()
+    seed = random.PRNGKey(0)
+    idata, num_samples = sbc_instance._get_posterior_samples(seed, prior_pred)
+    assert "posterior" in idata
+    assert num_samples == 100
+
+def test_run_simulations(sbc_instance):
+    """
+    Test that the simulations for SBC are run correctly.
+    """
+    sbc_instance.run_simulations()
+    assert sbc_instance._simulations_complete == sbc_instance.num_simulations
+    assert "mu" in sbc_instance.simulations
+
+def test_plot_results(sbc_instance):
+    """
+    Test that the results are plotted.
+    """
+    sbc_instance.run_simulations()
+    fig, axes = sbc_instance.plot_results()
+    assert fig is not None
+    assert axes is not None