1 files changed, 39 insertions, 25 deletions
diff --git a/tests/test_constraints.py b/tests/test_constraints.py
index 5e938a9e..15d360c2 100644
--- a/tests/test_constraints.py
+++ b/tests/test_constraints.py
@@ -2,61 +2,75 @@ import pytest
 
 from snakeoil.constraints import Problem
 
+
 def any_of(**kwargs):
     return any(kwargs.values())
 
+
 def all_of(**kwargs):
     return all(kwargs.values())
 
+
 def test_readd_variables():
     p = Problem()
-    p.add_variable((True, False), 'x', 'y')
+    p.add_variable((True, False), "x", "y")
     with pytest.raises(AssertionError, match="variable 'y' was already added"):
-        p.add_variable((True, False), 'y', 'z')
+        p.add_variable((True, False), "y", "z")
+
 
 def test_constraint_unknown_variable():
     p = Problem()
-    p.add_variable((True, False), 'x', 'y')
+    p.add_variable((True, False), "x", "y")
     with pytest.raises(AssertionError, match="unknown variable 'z'"):
-        p.add_constraint(any_of, ('y', 'z'))
+        p.add_constraint(any_of, ("y", "z"))
+
 
 def test_empty_problem():
     p = Problem()
-    assert tuple(p) == ({}, )
+    assert tuple(p) == ({},)
+
 
 def test_empty_constraints():
     p = Problem()
-    p.add_variable((True, False), 'x', 'y')
-    p.add_variable((True, ), 'z')
+    p.add_variable((True, False), "x", "y")
+    p.add_variable((True,), "z")
     assert len(tuple(p)) == 4
 
+
 def test_domain_prefer_later():
     p = Problem()
-    p.add_variable((False, True), 'x', 'y')
-    p.add_constraint(any_of, ('x', 'y'))
-    assert next(iter(p)) == {'x': True, 'y': True}
+    p.add_variable((False, True), "x", "y")
+    p.add_constraint(any_of, ("x", "y"))
+    assert next(iter(p)) == {"x": True, "y": True}
+
 
 def test_constraint_single_variable():
     p = Problem()
-    p.add_variable((True, False), 'x', 'y')
-    p.add_constraint(lambda x: x, ('x', ))
-    p.add_constraint(lambda y: not y, ('y', ))
-    assert tuple(p) == ({'x': True, 'y': False}, )
+    p.add_variable((True, False), "x", "y")
+    p.add_constraint(lambda x: x, ("x",))
+    p.add_constraint(lambda y: not y, ("y",))
+    assert tuple(p) == ({"x": True, "y": False},)
+
 
 def test_no_solution():
     p = Problem()
-    p.add_variable((True, ), 'x')
-    p.add_variable((True, False), 'y', 'z')
-    p.add_constraint(lambda x, y: not x or y, ('x', 'y'))
-    p.add_constraint(lambda y, z: not y or not z, ('y', 'z'))
-    p.add_constraint(lambda x, z: not x or z, ('x', 'z'))
+    p.add_variable((True,), "x")
+    p.add_variable((True, False), "y", "z")
+    p.add_constraint(lambda x, y: not x or y, ("x", "y"))
+    p.add_constraint(lambda y, z: not y or not z, ("y", "z"))
+    p.add_constraint(lambda x, z: not x or z, ("x", "z"))
     assert not tuple(p)
 
+
 def test_forward_check():
     p = Problem()
-    p.add_variable(range(2, 10), 'x', 'y', 'z')
-    p.add_constraint(lambda x, y: (x + y) % 2 == 0, ('x', 'y'))
-    p.add_constraint(lambda x, y, z: (x * y * z) % 2 != 0, ('x', 'y', 'z'))
-    p.add_constraint(lambda y, z: y < z, ('y', 'z'))
-    p.add_constraint(lambda z, x: x ** 2 <= z, ('x', 'z'))
-    assert tuple(p) == ({'x': 3, 'y': 7, 'z': 9}, {'x': 3, 'y': 5, 'z': 9}, {'x': 3, 'y': 3, 'z': 9})
+    p.add_variable(range(2, 10), "x", "y", "z")
+    p.add_constraint(lambda x, y: (x + y) % 2 == 0, ("x", "y"))
+    p.add_constraint(lambda x, y, z: (x * y * z) % 2 != 0, ("x", "y", "z"))
+    p.add_constraint(lambda y, z: y < z, ("y", "z"))
+    p.add_constraint(lambda z, x: x**2 <= z, ("x", "z"))
+    assert tuple(p) == (
+        {"x": 3, "y": 7, "z": 9},
+        {"x": 3, "y": 5, "z": 9},
+        {"x": 3, "y": 3, "z": 9},
+    )