fix error with very large ints in to_jsonable

hypothesis-python/RELEASE.rst

@@ -0,0 +1,3 @@
+RELEASE_TYPE: patch
+
+This patch fixes an error when generating :doc:`observability <observability>` reports involving large (``n > 1e308``) integers.

hypothesis-python/src/hypothesis/strategies/_internal/utils.py

@@ -17,6 +17,7 @@
 
 from hypothesis.internal.cache import LRUReusedCache
 from hypothesis.internal.compat import dataclass_asdict
+from hypothesis.internal.conjecture.junkdrawer import clamp
 from hypothesis.internal.floats import float_to_int
 from hypothesis.internal.reflection import proxies
 from hypothesis.vendor.pretty import pretty
@@ -160,6 +161,9 @@ def to_jsonable(obj: object) -> object:
     """
     if isinstance(obj, (str, int, float, bool, type(None))):
         if isinstance(obj, int) and abs(obj) >= 2**63:
+            # Silently clamp very large ints to max_float, to avoid
+            # OverflowError when casting to float.
+            obj = clamp(-sys.float_info.max, obj, sys.float_info.max)
             return float(obj)
         return obj
     if isinstance(obj, (list, tuple, set, frozenset)):

hypothesis-python/tests/cover/test_searchstrategy.py

@@ -11,6 +11,7 @@
 import dataclasses
 import functools
 import random
+import sys
 from collections import defaultdict, namedtuple
 
 import attr
@@ -153,3 +154,9 @@ def test_jsonable_large_ints_are_floats():
     n = 2**63
     assert isinstance(to_jsonable(n), float)
     assert to_jsonable(n) == float(n)
+
+
+def test_jsonable_very_large_ints():
+    # previously caused OverflowError when casting to float.
+    n = 2**1024
+    assert to_jsonable(n) == sys.float_info.max