properly clamp signed zeroes

hypothesis-python/src/hypothesis/internal/conjecture/junkdrawer.py

@@ -272,6 +272,13 @@ def __underlying_index(self, i: int) -> int:
 def clamp(lower: float, value: float, upper: float) -> float:
     """Given a value and lower/upper bounds, 'clamp' the value so that
     it satisfies lower <= value <= upper."""
+    # this seems pointless (and is for integers), but handles the -0.0/0.0 case.
+    # clamp(-1, 0.0, -0.0) violates the bounds by returning 0.0, since min(0.0, -0.0)
+    # takes the first value of 0.0.
+    if value == lower:
+        return lower
+    if value == upper:
+        return upper
     return max(lower, min(value, upper))
 
 

hypothesis-python/tests/conjecture/test_junkdrawer.py

@@ -26,6 +26,7 @@
     stack_depth_of_caller,
     startswith,
 )
+from hypothesis.internal.floats import float_to_int, sign_aware_lte
 
 
 def test_out_of_range():
@@ -66,20 +67,22 @@ def test_pop():
 @example(1, 10, 5)
 @example(5, 10, 5)
 @example(5, 1, 10)
-@given(st.integers(), st.integers(), st.integers())
+@example(-5, 0.0, -0.0)
+@example(0.0, -0.0, 5)
+@given(
+    st.floats(allow_nan=False), st.floats(allow_nan=False), st.floats(allow_nan=False)
+)
 def test_clamp(lower, value, upper):
     lower, upper = sorted((lower, upper))
-
     clamped = clamp(lower, value, upper)
 
-    assert lower <= clamped <= upper
-
-    if lower <= value <= upper:
-        assert value == clamped
+    assert sign_aware_lte(lower, clamped) and sign_aware_lte(clamped, upper)
+    if sign_aware_lte(lower, value) and sign_aware_lte(value, upper):
+        assert float_to_int(value) == float_to_int(clamped)
     if lower > value:
-        assert clamped == lower
+        assert float_to_int(clamped) == float_to_int(lower)
     if value > upper:
-        assert clamped == upper
+        assert float_to_int(clamped) == float_to_int(upper)
 
 
 # this would be more robust as a stateful test, where each rule is a list operation

hypothesis-python/tests/cover/test_float_utils.py

@@ -70,6 +70,7 @@ def test_next_float_equal(func, val):
 @example(float_kw(1, 4, smallest_nonzero_magnitude=4), -4)
 @example(float_kw(1, 4, smallest_nonzero_magnitude=4), -5)
 @example(float_kw(1, 4, smallest_nonzero_magnitude=4), -6)
+@example(float_kw(-5e-324, -0.0, smallest_nonzero_magnitude=5e-324), 3.0)
 @given(float_kwargs(), st.floats())
 def test_float_clamper(kwargs, input_value):
     min_value = kwargs["min_value"]