fix(telemetry): write every zero Decimal as 0

packages/aws-durable-execution-sdk-python-telemetry-exporter/README.md

@@ -331,8 +331,8 @@ and converted to plain JSON:
   `2**53 - 1`. Otherwise a float when the float round-trips exactly and is
   within DynamoDB's number range (magnitude 1E-130 to 9.99...E+125). Otherwise `str(value)`, for example `"9007199254740993"`,
   `"12345678901234567.89"` or `"1E+299"`. NaN and Infinity become `null`.
-  Negative zero (`Decimal("-0")`, `Decimal("-0.0")`) is integral, so it becomes
-  `0` and loses its sign.
+  Every zero, of any sign or exponent (`Decimal("-0")`, `Decimal("-0E+20")`),
+  becomes `0` and loses its sign.
 - `datetime` and `date`: `isoformat()`. `UUID`: string. `bytes`: base64.
   `tuple`: list. `BatchResult`: `to_dict()`.
 

packages/aws-durable-execution-sdk-python-telemetry-exporter/src/aws_durable_execution_sdk_python_telemetry_exporter/plugin.py

@@ -276,7 +276,7 @@ def _to_json_compatible(value: Any) -> Any:
     ``Decimal``: an int when integral and ``abs(n) <= 2**53 - 1``, else a float
     when it round-trips exactly and is within DynamoDB's number range
     (magnitude 1E-130 to 9.99...E+125), else ``str(value)``; NaN and Infinity
-    become ``None``. Negative zero becomes ``0``. ``datetime`` / ``date`` -> ``isoformat()``, ``UUID`` -> string,
+    become ``None``. Every zero, of any sign or exponent, becomes ``0``. ``datetime`` / ``date`` -> ``isoformat()``, ``UUID`` -> string,
     ``bytes`` -> base64, ``tuple`` -> list, ``BatchResult`` -> ``to_dict()``.
     Non-finite floats become ``None``.
     """
@@ -315,6 +315,10 @@ def _scalar_to_json_compatible(value: Any) -> Any:
     if isinstance(value, decimal.Decimal):
         if not value.is_finite():
             return None
+        # A zero of any sign or exponent ("-0E+20", "0E+16") is integer 0.
+        # Its adjusted() can be large, so the integer check below would miss it.
+        if value.is_zero():
+            return 0
         # adjusted() is checked first so Decimal("1E+1000000") never builds a
         # million-digit int.
         if (
@@ -324,9 +328,7 @@ def _scalar_to_json_compatible(value: Any) -> Any:
             as_int = int(value)
             if abs(as_int) <= _MAX_SAFE_INTEGER:
                 return as_int
-        if value and not (
-            _MIN_NUMBER_ADJUSTED <= value.adjusted() <= _MAX_NUMBER_ADJUSTED
-        ):
+        if not (_MIN_NUMBER_ADJUSTED <= value.adjusted() <= _MAX_NUMBER_ADJUSTED):
             return str(value)
         as_float = float(value)
         written = decimal.Decimal(repr(as_float))

packages/aws-durable-execution-sdk-python-telemetry-exporter/tests/test_error_and_result_format.py

@@ -243,6 +243,9 @@ def test_batch_result_becomes_to_dict():
         ("12", 12),
         ("-0", 0),
         ("-0.0", 0),
+        ("-0E+20", 0),
+        ("0E+16", 0),
+        ("0E-200", 0),
         ("1.10", 1.1),
         ("0.1", 0.1),
         ("9007199254740991", 9007199254740991),