Optimized Range.overlap, 1.25x speedup.

doc/changelog.rst

@@ -13,7 +13,8 @@ This release is a preparation for a stable 1.0 release.
 
 - Renamed classes to match :pep:`8#class-names` conventions. This does not apply
   to classes that works on built-in that does not follow :pep:`8#class-names`.
-- Optimized :meth:`~spans.types.Range.union`, 1.3x speedup.
+- Optimized :meth:`~spans.types.Range.overlap`, 1.3x speedup.
+- Optimized :meth:`~spans.types.Range.union`, 1.25x speedup.
 
 
 Version 0.4.0

spans/types.py

@@ -351,7 +351,16 @@ def overlap(self, other):
         See also :meth:`~spans.types.Range.intersection`.
         """
 
-        return not self << other and not other << self
+        if self < other:
+            a, b = self, other
+        else:
+            a, b = other, self
+
+        # We need to explicitly handle unbounded ranges since a.upper and b.lower
+        # make the intervals seem adjacent even though they are not
+        if a.upper_inf or b.lower_inf:
+            return True
+        return a.upper > b.lower or a.upper == b.lower and a.upper_inc and b.lower_inc
 
     def adjacent(self, other):
         """

tests/test_range.py

@@ -291,21 +291,25 @@ def test_within_type_check(value):
 
 
 @pytest.mark.parametrize("a, b", [
-    (intrange(1, 5, upper_inc=True), intrange(5, 10)),
-    (intrange(1, 5), intrange(3, 8)),
-    (intrange(3, 8), intrange(1, 5)),
-    (intrange(1, 10), intrange(5)),
+    (floatrange(1.0, 5.0, upper_inc=True), floatrange(5.0, 10.0)),
+    (floatrange(1.0, 5.0), floatrange(3.0, 8.0)),
+    (floatrange(1.0, 10.0), floatrange(5.0)),
+    (floatrange(upper=10.0), floatrange(1.0, 5.0)),
+    (floatrange(1.0), floatrange()),
 ])
 def test_overlap(a, b):
     assert a.overlap(b)
+    assert b.overlap(a)
 
 
 @pytest.mark.parametrize("a, b", [
-    (intrange(1, 5), intrange(5, 10)),
-    (intrange(1, 5), intrange(5, 10, lower_inc=False)),
+    (floatrange(1.0, 5.0), floatrange(5.0, 10.0)),
+    (floatrange(1.0, 5.0), floatrange(5.0, 10.0, lower_inc=False)),
+    (floatrange(upper=5.0), floatrange(5.0)),
 ])
 def test_not_overlap(a, b):
     assert not a.overlap(b)
+    assert not b.overlap(a)
 
 
 @pytest.mark.parametrize("a, b", [