SERVER-43964 UUID etc need not befriend IDL types

2 files changed, 12 insertions, 30 deletions

diff --git a/buildscripts/idl/idl/cpp_types.py b/buildscripts/idl/idl/cpp_types.py
index d4066af197f..bb7ec7d0a22 100644
--- a/buildscripts/idl/idl/cpp_types.py
+++ b/buildscripts/idl/idl/cpp_types.py
@@ -56,24 +56,6 @@ def is_primitive_scalar_type(cpp_type):
     ]
 
 
-def get_primitive_scalar_type_default_value(cpp_type):
-    # type: (str) -> str
-    """
-    Return a default value for a primitive scalar type.
-
-    Assumes the IDL generated code verifies the user sets the value before serialization.
-    """
-    # pylint: disable=invalid-name
-    assert is_primitive_scalar_type(cpp_type)
-    if cpp_type == 'bool':
-        return 'false'
-    # TODO (SERVER-50101): Remove 'FeatureCompatibility::Version' once IDL supports a command
-    # cpp_type of C++ enum.
-    if cpp_type == 'ServerGlobalParams::FeatureCompatibility::Version':
-        return 'ServerGlobalParams::FeatureCompatibility::Version::kUnsetDefault44Behavior'
-    return '-1'
-
-
 def is_primitive_type(cpp_type):
     # type: (str) -> bool
     """Return True if a cpp_type is a primitive type and should not be returned as reference."""
diff --git a/buildscripts/idl/idl/generator.py b/buildscripts/idl/idl/generator.py
index 34747fd6d24..3dc643b5075 100644
--- a/buildscripts/idl/idl/generator.py
+++ b/buildscripts/idl/idl/generator.py
@@ -1580,13 +1580,12 @@ class _CppSourceFileWriter(_CppFileWriterBase):
         if default_init:
             for field in struct.fields:
                 needs_init = (field.type and field.type.cpp_type and not field.type.is_array
-                              and cpp_types.is_primitive_scalar_type(field.type.cpp_type))
-
-                if _is_required_serializer_field(field) and needs_init:
+                              and _is_required_serializer_field(field)
+                              and field.cpp_name != 'dbName')
+                if needs_init:
                     initializers.append(
-                        '%s(%s)' % (_get_field_member_name(field),
-                                    cpp_types.get_primitive_scalar_type_default_value(
-                                        field.type.cpp_type)))
+                        '%s(mongo::idl::preparsedValue<decltype(%s)>())' %
+                        (_get_field_member_name(field), _get_field_member_name(field)))
 
         # Serialize the _dbName field second
         initializes_db_name = False
@@ -1760,13 +1759,13 @@ class _CppSourceFileWriter(_CppFileWriterBase):
 
                     if struct.command_field.type.cpp_type and cpp_types.is_primitive_scalar_type(
                             struct.command_field.type.cpp_type):
-                        self._writer.write_line('%s localCmdType(%s);' %
-                                                (cpp_type_info.get_storage_type(),
-                                                 cpp_types.get_primitive_scalar_type_default_value(
-                                                     struct.command_field.type.cpp_type)))
+                        self._writer.write_line(
+                            'auto localCmdType = mongo::idl::preparsedValue<%s>();' %
+                            (cpp_type_info.get_storage_type()))
                     else:
                         self._writer.write_line(
-                            '%s localCmdType;' % (cpp_type_info.get_storage_type()))
+                            'auto localCmdType = mongo::idl::preparsedValue<%s>();' %
+                            (cpp_type_info.get_storage_type()))
                     self._writer.write_line(
                         '%s object(localCmdType);' % (common.title_case(struct.cpp_name)))
                 elif struct.namespace in (common.COMMAND_NAMESPACE_CONCATENATE_WITH_DB,
@@ -1777,7 +1776,8 @@ class _CppSourceFileWriter(_CppFileWriterBase):
                 else:
                     assert False, "Missing case"
             else:
-                self._writer.write_line('%s object;' % common.title_case(struct.cpp_name))
+                self._writer.write_line('auto object = mongo::idl::preparsedValue<%s>();' %
+                                        common.title_case(struct.cpp_name))
 
             self._writer.write_line(method_info.get_call('object'))
             self._writer.write_line('return object;')