fix(serialization-form): preserve whitespace in string values

packages/serialization/form/kiota_serialization_form/form_serialization_writer.py

@@ -35,7 +35,7 @@ def write_str_value(self, key: Optional[str], value: Optional[str]) -> None:
         if key and value:
             if len(self.writer) > 0:
                 self.writer += "&"
-            self.writer += f"{quote_plus(key.strip())}={quote_plus(value.strip())}"
+            self.writer += f"{quote_plus(key.strip())}={quote_plus(value)}"
 
     def write_bool_value(self, key: Optional[str], value: Optional[bool]) -> None:
         """Writes the specified boolean value to the stream with an optional given key.

packages/serialization/form/tests/unit/test_form_serialization_writer.py

@@ -1,12 +1,29 @@
 from uuid import UUID
-from urllib.parse import unquote_plus
+from urllib.parse import parse_qs, unquote_plus
 import pytest
 
 from datetime import datetime, timedelta, date, time
 from kiota_serialization_form.form_serialization_writer import FormSerializationWriter
 from ..helpers import TestEntity, TestEnum
 
 
+@pytest.mark.parametrize("value", [
+    " padded ", "leading ", " trailing", " \t\r\n", "\u2003café\u2003", "plain",
+])
+def test_write_str_value_preserves_whitespace(value):
+    writer = FormSerializationWriter()
+    writer.write_str_value("label", value)
+    assert parse_qs(writer.get_serialized_content().decode("utf-8"))["label"] == [value]
+
+
+@pytest.mark.parametrize("value", [None, ""])
+def test_write_str_value_still_omits_absent_or_empty_values(value):
+    writer = FormSerializationWriter()
+    writer.write_str_value("first", "present")
+    writer.write_str_value("label", value)
+    assert writer.get_serialized_content() == b"first=present"
+
+
 @pytest.fixture
 def user_1():
     user = TestEntity()