Support float("inf") and float("nan") with experimental_python_types

Author: mdesmet

tests/integration/test_dbapi_integration.py

@@ -614,9 +614,8 @@ def test_float_query_param(trino_connection):
     assert rows[0][0] == 1.1
 
 
-@pytest.mark.skip(reason="Nan currently not returning the correct python type for nan")
 def test_float_nan_query_param(trino_connection):
-    cur = trino_connection.cursor()
+    cur = trino_connection.cursor(experimental_python_types=True)
     cur.execute("SELECT ?", params=(float("nan"),))
     rows = cur.fetchall()
 
@@ -625,15 +624,14 @@ def test_float_nan_query_param(trino_connection):
     assert math.isnan(rows[0][0])
 
 
-@pytest.mark.skip(reason="Nan currently not returning the correct python type fon inf")
 def test_float_inf_query_param(trino_connection):
-    cur = trino_connection.cursor()
+    cur = trino_connection.cursor(experimental_python_types=True)
     cur.execute("SELECT ?", params=(float("inf"),))
     rows = cur.fetchall()
 
     assert rows[0][0] == float("inf")
 
-    cur.execute("SELECT ?", params=(-float("-inf"),))
+    cur.execute("SELECT ?", params=(float("-inf"),))
     rows = cur.fetchall()
 
     assert rows[0][0] == float("-inf")

trino/client.py

@@ -61,6 +61,10 @@
 
 _HEADER_EXTRA_CREDENTIAL_KEY_REGEX = re.compile(r'^\S[^\s=]*$')
 
+INF = float("inf")
+NEGATIVE_INF = float("-inf")
+NAN = float("nan")
+
 
 class ClientSession(object):
     def __init__(
@@ -526,6 +530,14 @@ def _map_to_python_type(cls, item: Tuple[Any, Dict]) -> Any:
                 return [cls._map_to_python_type((array_item, raw_type)) for array_item in value]
             elif "decimal" in raw_type:
                 return Decimal(value)
+            elif raw_type == "double":
+                if value == 'Infinity':
+                    return INF
+                elif value == '-Infinity':
+                    return NEGATIVE_INF
+                elif value == 'NaN':
+                    return NAN
+                return value
             elif raw_type == "date":
                 return datetime.strptime(value, "%Y-%m-%d").date()
             elif raw_type == "timestamp with time zone":