diff --git a/src/y0/r_utils.py b/src/y0/r_utils.py
index 0744c1b8..df40cd46 100644
--- a/src/y0/r_utils.py
+++ b/src/y0/r_utils.py
@@ -1,16 +1,18 @@
 """General utilities for :mod:`rpy2`."""
 
+from __future__ import annotations
+
 import logging
 from collections.abc import Callable, Iterable
 from functools import lru_cache, wraps
 from typing import Any, TypeVar, cast
 
-from rpy2.robjects.packages import importr, isinstalled
+from rpy2.robjects.packages import InstalledPackage, InstalledSTPackage, importr, isinstalled
 from rpy2.robjects.vectors import StrVector
 
 from .dsl import Variable
 
-__all__ = ["uses_r"]
+__all__ = ["uses_r", "prepare_renv", "prepare_default_renv"]
 
 logger = logging.getLogger(__name__)
 
@@ -26,10 +28,11 @@
 Func = Callable[..., T]
 
 
-def prepare_renv(requirements: Iterable[str]) -> None:
+def prepare_renv(requirements: Iterable[str]) -> list[InstalledSTPackage | InstalledPackage]:
     """Ensure the given R packages are installed.
 
-    :param requirements: A list of R packages to ensure are installed
+    :param requirements: A list of R package names to ensure are installed
+    :returns: A list of R packages
 
     .. seealso:: https://rpy2.github.io/doc/v3.4.x/html/introduction.html#installing-packages
     """
@@ -46,8 +49,7 @@ def prepare_renv(requirements: Iterable[str]) -> None:
         logger.warning("installing R packages: %s", uninstalled_requirements)
         utils.install_packages(StrVector(uninstalled_requirements))
 
-    for requirement in requirements:
-        importr(requirement)
+    return [importr(requirement) for requirement in requirements]
 
 
 @lru_cache(maxsize=1)
diff --git a/tests/test_algorithm/test_counterfactual_transportability.py b/tests/test_algorithm/test_counterfactual_transportability.py
index 1086bea9..51c08c5c 100644
--- a/tests/test_algorithm/test_counterfactual_transportability.py
+++ b/tests/test_algorithm/test_counterfactual_transportability.py
@@ -460,7 +460,7 @@ def test_7(self):
         test7_in = W @ +X
         test7_out = {W @ +X}
         result = get_ancestors_of_counterfactual(event=test7_in, graph=figure_2a_graph)
-        logger.warning("In test_7: result = " + str(result))
+        logger.debug("In test_7: result = " + str(result))
         self.assertTrue(variable in test7_out for variable in result)
 
 
@@ -506,7 +506,7 @@ def test_inconsistent_1(self):
         """
         event = [(Y @ -X, -Y), (Y @ -X, +Y)]
         result = simplify(event=event, graph=figure_2a_graph)
-        logger.warning("Result for test_inconsistent_1 is " + str(result))
+        logger.debug("Result for test_inconsistent_1 is " + str(result))
         self.assertIsNone(simplify(event=event, graph=figure_2a_graph))
 
     def test_inconsistent_2(self):
@@ -630,11 +630,11 @@ def test_line_2_1(self):
         nonreflexive_variable_to_value_mappings[Y @ -X].add(-Y)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(+Y)
 
-        logger.warning(
+        logger.debug(
             "In test_line_2_1: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_1: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -652,11 +652,11 @@ def test_line_2_2(self):
         nonreflexive_variable_to_value_mappings = defaultdict(set)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(-Y)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(-Y)
-        logger.warning(
+        logger.debug(
             "In test_line_2_2: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_2: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -674,11 +674,11 @@ def test_line_2_10(self):
         nonreflexive_variable_to_value_mappings = defaultdict(set)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(None)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(None)
-        logger.warning(
+        logger.debug(
             "In test_line_2_10: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_10: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -695,11 +695,11 @@ def test_line_2_3(self):
         reflexive_variable_to_value_mappings[Y @ -Y].add(+Y)
 
         nonreflexive_variable_to_value_mappings = defaultdict(set)
-        logger.warning(
+        logger.debug(
             "In test_line_2_3: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_3: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -721,11 +721,11 @@ def test_line_2_11(self):
         reflexive_variable_to_value_mappings[Y @ -Y].add(None)
 
         nonreflexive_variable_to_value_mappings = defaultdict(set)
-        logger.warning(
+        logger.debug(
             "In test_line_2_11: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_11: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -743,11 +743,11 @@ def test_line_2_4(self):
 
         nonreflexive_variable_to_value_mappings = defaultdict(set)
 
-        logger.warning(
+        logger.debug(
             "In test_line_2_4: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_4: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -764,11 +764,11 @@ def test_line_2_5(self):
         reflexive_variable_to_value_mappings[Y @ +Y].add(-Y)
 
         nonreflexive_variable_to_value_mappings = defaultdict(set)
-        logger.warning(
+        logger.debug(
             "In test_line_2_5: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_5: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -786,11 +786,11 @@ def test_line_2_6(self):
         nonreflexive_variable_to_value_mappings = defaultdict(set)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(-Y)
         nonreflexive_variable_to_value_mappings[Y @ -Z].add(+Y)
-        logger.warning(
+        logger.debug(
             "In test_line_2_6: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_6: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -810,11 +810,11 @@ def test_line_2_7(self):
 
         nonreflexive_variable_to_value_mappings = defaultdict(set)
 
-        logger.warning(
+        logger.debug(
             "In test_line_2_7: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_7: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -841,11 +841,11 @@ def test_line_2_8(self):
         nonreflexive_variable_to_value_mappings[Y @ -X].add(-Y)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(None)
 
-        logger.warning(
+        logger.debug(
             "In test_line_2_8: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_8: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -869,11 +869,11 @@ def test_line_2_9(self):
         nonreflexive_variable_to_value_mappings = defaultdict(set)
         nonreflexive_variable_to_value_mappings[Y @ -X].add(-Y)
 
-        logger.warning(
+        logger.debug(
             "In test_line_2_9: nonreflexive_variable_to_value_mappings = "
             + str(nonreflexive_variable_to_value_mappings)
         )
-        logger.warning(
+        logger.debug(
             "In test_line_2_9: reflexive_variable_to_value_mappings = "
             + str(reflexive_variable_to_value_mappings)
         )
@@ -1777,7 +1777,7 @@ def test_transport_district_intervening_on_parents_2(self):
         ]
         domain_data = [({X}, PP[Pi1](W, X, Y, Z)), (set(), PP[Pi2](W, X, Y, Z))]
         expected_result = PP[Pi2](X | Z) * PP[Pi2](Z)
-        logger.warning(
+        logger.debug(
             "In test_transport_district_intervening_on_parents_2: expected_result is "
             + expected_result.to_latex()
         )
@@ -2485,8 +2485,8 @@ def test_transport_unconditional_counterfactual_query_1(self):
             domain_graphs=domain_graphs,
             domain_data=domain_data,
         )
-        logger.warning("Result_expr = " + result_expr.to_latex())
-        logger.warning("Result_event = " + str(result_event))
+        logger.debug("Result_expr = " + result_expr.to_latex())
+        logger.debug("Result_event = " + str(result_event))
         self.assert_expr_equal(expected_result, result_expr)
 
     def test_transport_unconditional_counterfactual_query_2(self):
@@ -2550,8 +2550,8 @@ def test_transport_unconditional_counterfactual_query_3(self):
             domain_graphs=domain_graphs,
             domain_data=domain_data,
         )
-        logger.warning("Result_expr = " + result_expr.to_latex())
-        logger.warning("Result_event = " + str(result_event))
+        logger.debug("Result_expr = " + result_expr.to_latex())
+        logger.debug("Result_event = " + str(result_event))
         self.assert_expr_equal(expected_result, result_expr)
         self.assertCountEqual(event, result_event)
         # Test sending variables with a value of None into this algorithm
@@ -3185,10 +3185,10 @@ def test_transport_conditional_counterfactual_query_1(self):
             domain_graphs=self.example_1_domain_graphs,
             domain_data=domain_data,
         )
-        logger.warning("expected_result_expr = " + expected_result_expr.to_latex())
-        logger.warning("expected_result_event = " + str(expected_result_event))
-        logger.warning("Result_expr = " + result_expr.to_latex())
-        logger.warning("Result_event = " + str(result_event))
+        logger.debug("expected_result_expr = " + expected_result_expr.to_latex())
+        logger.debug("expected_result_event = " + str(expected_result_event))
+        logger.debug("Result_expr = " + result_expr.to_latex())
+        logger.debug("Result_event = " + str(result_event))
         self.assert_expr_equal(expected_result_expr, result_expr)
         self.assertCountEqual(expected_result_event, result_event)
 
@@ -3239,10 +3239,10 @@ def test_transport_conditional_counterfactual_query_2(self):
             domain_graphs=self.example_2_domain_graphs,
             domain_data=domain_data,
         )
-        logger.warning("expected_result_expr = " + expected_result_expr.to_latex())
-        logger.warning("expected_result_event = " + str(expected_result_event))
-        logger.warning("Result_expr = " + result_expr.to_latex())
-        logger.warning("Result_event = " + str(result_event))
+        logger.debug("expected_result_expr = " + expected_result_expr.to_latex())
+        logger.debug("expected_result_event = " + str(expected_result_event))
+        logger.debug("Result_expr = " + result_expr.to_latex())
+        logger.debug("Result_event = " + str(result_event))
         self.assert_expr_equal(expected_result_expr, result_expr)
         self.assertCountEqual(expected_result_event, result_event)
 
@@ -3588,10 +3588,10 @@ def test_transport_conditional_counterfactual_query_5(self):
             domain_graphs=self.example_1_domain_graphs,
             domain_data=domain_data,
         )
-        logger.warning("expected_result_expr = " + expected_result_expr.to_latex())
-        logger.warning("expected_result_event = " + str(expected_result_event))
-        logger.warning("Result_expr = " + result_expr.to_latex())
-        logger.warning("Result_event = " + str(result_event))
+        logger.debug("expected_result_expr = " + expected_result_expr.to_latex())
+        logger.debug("expected_result_event = " + str(expected_result_event))
+        logger.debug("Result_expr = " + result_expr.to_latex())
+        logger.debug("Result_event = " + str(result_event))
         self.assert_expr_equal(expected_result_expr, result_expr)
         self.assertCountEqual(expected_result_event, result_event)
 
@@ -3621,10 +3621,10 @@ def test_transport_conditional_counterfactual_query_6(self):
             domain_graphs=self.example_1_domain_graphs,
             domain_data=domain_data,
         )
-        logger.warning("expected_result_expr = " + expected_result_expr.to_latex())
-        logger.warning("expected_result_event = " + str(expected_result_event))
-        logger.warning("Result_expr = " + result_expr.to_latex())
-        logger.warning("Result_event = " + str(result_event))
+        logger.debug("expected_result_expr = " + expected_result_expr.to_latex())
+        logger.debug("expected_result_event = " + str(expected_result_event))
+        logger.debug("Result_expr = " + result_expr.to_latex())
+        logger.debug("Result_event = " + str(result_event))
         self.assert_expr_equal(expected_result_expr, result_expr)
         self.assertCountEqual(expected_result_event, result_event)
 
@@ -6036,8 +6036,8 @@ def test_merge_frozen_sets_linked_by_bidirectional_edges(self):
             input_sets=test_2_inputs, graph=graph_2
         )
         expected_result_2 = {frozenset([W, Y]), frozenset([X]), frozenset([W1]), frozenset([R, Z])}
-        logger.warning(str(expected_result_2))
-        logger.warning(str(result_2))
+        logger.debug(str(expected_result_2))
+        logger.debug(str(result_2))
         self.assertSetEqual(result_2, expected_result_2)
         graph_3 = NxMixedGraph.from_edges(directed=[], undirected=[(W, X), (X, Y), (R, Z), (W1, Y)])
         result_3 = _merge_frozen_sets_linked_by_bidirectional_edges(
diff --git a/tests/test_algorithm/test_falsification.py b/tests/test_algorithm/test_falsification.py
index f444939a..a89bb53a 100644
--- a/tests/test_algorithm/test_falsification.py
+++ b/tests/test_algorithm/test_falsification.py
@@ -1,6 +1,7 @@
 """Test falsification of testable implications given a graph."""
 
 import unittest
+import warnings
 
 import numpy as np
 import pandas as pd
@@ -19,7 +20,8 @@ def test_discrete_graph_falsifications(self):
         for method in [None, *get_conditional_independence_tests()]:
             if method == "pearson":
                 continue
-            with self.subTest(method=method):
+            with self.subTest(method=method), warnings.catch_warnings():
+                warnings.simplefilter(action="ignore", category=FutureWarning)
                 issues = get_graph_falsifications(
                     asia_example.graph, asia_example.data, method=method
                 )
diff --git a/tests/test_algorithm/test_tian_pearl_identify.py b/tests/test_algorithm/test_tian_pearl_identify.py
index 8514a21d..d3021ef3 100644
--- a/tests/test_algorithm/test_tian_pearl_identify.py
+++ b/tests/test_algorithm/test_tian_pearl_identify.py
@@ -240,7 +240,7 @@ def test_identify_1(self):
             graph=soft_interventions_figure_1b_graph,
             topo=list(soft_interventions_figure_1b_graph.topological_sort()),
         )
-        logger.warning("Result of identify() call for test_identify_1 is " + result.to_latex())
+        logger.debug("Result of identify() call for test_identify_1 is " + result.to_latex())
         self.assert_expr_equal(result, PP[Pi1](Z | X1))
 
     def test_identify_2(self):
@@ -259,7 +259,7 @@ def test_identify_2(self):
             graph=soft_interventions_figure_2a_graph,
             topo=list(soft_interventions_figure_2a_graph.topological_sort()),
         )
-        logger.warning("Result of identify() call for test_identify_2 part 1 is " + str(result1))
+        logger.debug("Result of identify() call for test_identify_2 part 1 is " + str(result1))
         self.assertIsNone(result1)
         result2 = identify_district_variables(
             input_variables=frozenset({Z, R}),
@@ -285,7 +285,7 @@ def test_identify_3(self):
             graph=soft_interventions_figure_2d_graph,
             topo=list(soft_interventions_figure_2d_graph.topological_sort()),
         )
-        logger.warning("Result of identify() call for test_identify_3 is " + str(result1))
+        logger.debug("Result of identify() call for test_identify_3 is " + str(result1))
         self.assertIsNone(result1)
         result2 = identify_district_variables(
             input_variables=frozenset({Z, R}),
@@ -294,7 +294,7 @@ def test_identify_3(self):
             graph=soft_interventions_figure_3_graph,
             topo=list(soft_interventions_figure_3_graph.topological_sort()),
         )
-        logger.warning("Result of identify() call for test_identify_3 is " + str(result2))
+        logger.debug("Result of identify() call for test_identify_3 is " + str(result2))
         self.assertIsNone(result2)
 
     def test_identify_4(self):
@@ -381,8 +381,8 @@ def test_identify_4_with_population_probabilities(self):
             graph=tian_pearl_figure_9a_graph,
             topo=list(tian_pearl_figure_9a_graph.topological_sort()),
         )
-        logger.warning("Result from identify_district_variables: " + result_4.to_latex())
-        logger.warning("  Expected result: " + expected_result.to_latex())
+        logger.debug("Result from identify_district_variables: " + result_4.to_latex())
+        logger.debug("  Expected result: " + expected_result.to_latex())
         self.assert_expr_equal(result_4, expected_result)
 
 
@@ -523,11 +523,11 @@ def test_compute_c_factor_5_with_population_probabilities(self):
             subgraph_probability=subgraph_probability,
             graph_topo=topo,
         )
-        logger.warning(
+        logger.debug(
             "In test_compute_c_factor_5_with_population_probabilities: expected_result = "
             + expected_result_5.to_latex()
         )
-        logger.warning(
+        logger.debug(
             "In test_compute_c_factor_5_with_population_probabilities: result = "
             + result_5.to_latex()
         )
@@ -711,7 +711,7 @@ def test_compute_c_factor_marginalizing_over_topological_successors_part_1(self)
             graph_probability=Sum.safe(self.result_piece, [W3]),
             topo=list(tian_pearl_figure_9a_graph.subgraph({W1, W2, X, Y}).topological_sort()),
         )
-        logger.warning(
+        logger.debug(
             "In first test of Lemma 4(ii): expecting this result: " + str(self.expected_result_1)
         )
         self.assert_expr_equal(result, self.expected_result_1)
@@ -721,10 +721,10 @@ def test_compute_c_factor_marginalizing_over_topological_successors_part_2(self)
 
         Source: The example on p. 30 of [Tian03a]_, run initially through [tikka20a]_.
         """
-        logger.warning(
+        logger.debug(
             "In second test of Lemma 4(ii): expecting this result: " + str(self.expected_result_2)
         )
-        logger.warning("Expected_result_1 = " + str(self.expected_result_1))
+        logger.debug("Expected_result_1 = " + str(self.expected_result_1))
         result = compute_c_factor_marginalizing_over_topological_successors(
             district={Y},
             graph_probability=Sum.safe(self.expected_result_1, [W1]),
@@ -742,7 +742,7 @@ def test_compute_c_factor_marginalizing_over_topological_successors_part_3(self)
             graph_probability=Sum.safe(self.result_piece_pp, [W3]),
             topo=list(tian_pearl_figure_9a_graph.subgraph({W1, W2, X, Y}).topological_sort()),
         )
-        logger.warning(
+        logger.debug(
             "In first test of Lemma 4(ii): expecting this result: "
             + self.expected_result_1_pp.to_latex()
         )
@@ -753,17 +753,17 @@ def test_compute_c_factor_marginalizing_over_topological_successors_part_4(self)
 
         Source: The example on p. 30 of [Tian03a]_, run initially through [tikka20a]_.
         """
-        logger.warning(
+        logger.debug(
             "In second test of Lemma 4(ii): expecting this result: "
             + self.expected_result_2.to_latex()
         )
-        logger.warning("Expected_result_1 = " + self.expected_result_1_pp.to_latex())
+        logger.debug("Expected_result_1 = " + self.expected_result_1_pp.to_latex())
         result = compute_c_factor_marginalizing_over_topological_successors(
             district={Y},
             graph_probability=Sum.safe(self.expected_result_1_pp, [W1]),
             topo=list(tian_pearl_figure_9a_graph.subgraph({X, Y}).topological_sort()),
         )
-        logger.warning("Expected result = " + self.expected_result_2_pp.to_latex())
+        logger.debug("Expected result = " + self.expected_result_2_pp.to_latex())
         self.assert_expr_equal(result, self.expected_result_2_pp)
 
 
diff --git a/tests/test_causaleffect.py b/tests/test_causaleffect.py
index 6e58b20e..c70802c8 100644
--- a/tests/test_causaleffect.py
+++ b/tests/test_causaleffect.py
@@ -9,7 +9,7 @@
 
 try:
     from y0.causaleffect import r_get_verma_constraints
-    from y0.r_utils import CAUSALEFFECT, IGRAPH
+    from y0.r_utils import CAUSALEFFECT, IGRAPH, prepare_renv
     from y0.struct import VermaConstraint
 except ImportError:  # rpy2 is not installed
     missing_rpy2 = True
@@ -30,13 +30,10 @@ class TestCausalEffect(unittest.TestCase):
     @classmethod
     def setUpClass(cls) -> None:
         """Make imports for the class."""
-        from rpy2.robjects.packages import PackageNotInstalledError, importr
-
         try:
-            importr(CAUSALEFFECT)
-            importr(IGRAPH)
-        except PackageNotInstalledError:
-            raise unittest.SkipTest("R packages not properly installed.") from None
+            prepare_renv([CAUSALEFFECT, IGRAPH])
+        except Exception as e:
+            raise unittest.SkipTest(f"R packages not properly installed.\n\n{e}") from None
 
     def test_verma_constraint(self):
         """Test getting the single Verma constraint from the Figure 1A graph."""
diff --git a/tests/test_mutate/test_chain.py b/tests/test_mutate/test_chain.py
index b4cc294b..7304f7f4 100644
--- a/tests/test_mutate/test_chain.py
+++ b/tests/test_mutate/test_chain.py
@@ -1,6 +1,7 @@
 """Tests for chain mutations."""
 
 import unittest
+import warnings
 
 from y0.dsl import A, B, P, Sum, W, X, Y, Z
 from y0.mutate import bayes_expand, chain_expand, fraction_expand
@@ -42,7 +43,10 @@ def test_fraction_expand(self):
 
     def test_bayes_expand(self):
         """Test expanding a conditional using extended Bayes' Theorem."""
-        self.assertEqual(P(A, X), bayes_expand(P(A, X)))
-        self.assertEqual(P(A, X) / Sum[A](P(A, X)), bayes_expand(P(A | X)))
-        self.assertEqual(P(A, X, Y) / Sum[A](P(A, X, Y)), bayes_expand(P(A | (X, Y))))
-        self.assertEqual(P(A, B, X, Y) / Sum[A, B](P(A, B, X, Y)), bayes_expand(P(A & B | (X, Y))))
+        with warnings.catch_warnings():
+            self.assertEqual(P(A, X), bayes_expand(P(A, X)))
+            self.assertEqual(P(A, X) / Sum[A](P(A, X)), bayes_expand(P(A | X)))
+            self.assertEqual(P(A, X, Y) / Sum[A](P(A, X, Y)), bayes_expand(P(A | (X, Y))))
+            self.assertEqual(
+                P(A, B, X, Y) / Sum[A, B](P(A, B, X, Y)), bayes_expand(P(A & B | (X, Y)))
+            )