Defer a few more matplotlib imports

openmc/model/surface_composite.py

@@ -6,7 +6,6 @@ import operator
 
 import numpy as np
 from scipy.spatial import ConvexHull, Delaunay
-from matplotlib.path import Path
 
 import openmc
 from openmc.checkvalue import (check_greater_than, check_value,
@@ -1021,6 +1020,7 @@ class Polygon(CompositeSurface):
         -------
         surfsets : a list of lists of surface, operator pairs
         """
+        from matplotlib.path import Path
 
         # Get centroids of all the simplices and determine if they are inside
         # the polygon defined by input vertices or not.

tests/regression_tests/python_import/test.py

@@ -1,7 +0,0 @@
-import sys
-import openmc
-
-
-def test_matplotlib_presence():
-    """Checks that remains a deferred import"""
-    assert 'matplotlib.pyplot' not in sys.modules

tests/test_matplotlib_import.py

@@ -0,0 +1,6 @@
+import sys
+import openmc
+
+def test_matplotlib_presence():
+    """Checks that matplotlib remains a deferred import"""
+    assert 'matplotlib' not in sys.modules

tests/unit_tests/test_plotter.py

@@ -1,7 +1,6 @@
 import numpy as np
 import openmc
 import pytest
-from matplotlib.figure import Figure
 
 
 @pytest.fixture(scope='module')
@@ -74,8 +73,10 @@ def test_calculate_cexs_with_materials(test_mat):
 
 @pytest.mark.parametrize("this", ["Be", "Be9"])
 def test_plot_xs(this):
-    assert isinstance(openmc.plotter.plot_xs(this, types=['total']), Figure)
+    from matplotlib.figure import Figure
+    assert isinstance(openmc.plot_xs(this, types=['total']), Figure)
 
 
 def test_plot_xs_mat(test_mat):
-    assert isinstance(openmc.plotter.plot_xs(test_mat, types=['total']), Figure)
+    from matplotlib.figure import Figure
+    assert isinstance(openmc.plot_xs(test_mat, types=['total']), Figure)