add tests for overriding simulators

Author: Kucharssim

tests/test_simulators/conftest.py

@@ -148,6 +148,35 @@ def two_moons_simulator(request):
     return request.getfixturevalue(request.param)
 
 
+@pytest.fixture()
+def composite_gaussian():
+    from bayesflow.simulators import make_simulator
+
+    def context():
+        n = np.random.randint(10, 100)
+        return dict(n=n)
+
+    def prior():
+        mu = np.random.normal(0, 1)
+        return dict(mu=mu)
+
+    def likelihood(mu, n):
+        y = np.random.normal(mu, 1, n)
+        return dict(y=y)
+
+    return make_simulator([prior, likelihood], meta_fn=context)
+
+
+@pytest.fixture()
+def fixed_n():
+    return 5
+
+
+@pytest.fixture()
+def fixed_mu():
+    return 100
+
+
 @pytest.fixture(
     params=[
         "bernoulli_glm",

tests/test_simulators/test_simulators.py

@@ -38,3 +38,12 @@ def test_sample(simulator, batch_size):
 
         # test batch randomness
         assert not np.allclose(value, value[0])
+
+
+def test_fixed_sample(composite_gaussian, batch_size, fixed_n, fixed_mu):
+    samples = composite_gaussian.sample((batch_size,), n=fixed_n, mu=fixed_mu)
+
+    assert samples["n"] == fixed_n
+    assert samples["mu"].shape == (batch_size, 1)
+    assert np.all(samples["mu"] == fixed_mu)
+    assert samples["y"].shape == (batch_size, fixed_n)