From 011810aa420f751492395c7251cf6e730b945b74 Mon Sep 17 00:00:00 2001
From: Fabio Zadrozny <fabiofz@gmail.com>
Date: Sun, 19 Apr 2020 13:42:27 -0300
Subject: [PATCH] Change __len__ to len().

---
 .../pydevd/_pydevd_bundle/pydevd_constants.py |  1 +
 .../pydevd/_pydevd_bundle/pydevd_resolver.py  | 36 +++++++++----------
 .../_pydevd_bundle/pydevd_suspended_frames.py |  4 +--
 .../pydevd/_pydevd_bundle/pydevd_utils.py     |  6 ++--
 .../pydevd/tests_python/test_debugger_json.py | 10 +++---
 .../pydevd/tests_python/test_resolvers.py     | 32 +++++++----------
 .../test_suspended_frames_manager.py          | 10 +++---
 tests/debug/config.py                         |  7 +++-
 tests/debugpy/test_evaluate.py                | 24 ++++++-------
 9 files changed, 64 insertions(+), 66 deletions(-)

diff --git a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_constants.py b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_constants.py
index 254273b2..fbdea662 100644
--- a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_constants.py
+++ b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_constants.py
@@ -71,6 +71,7 @@ except AttributeError:
 MAXIMUM_VARIABLE_REPRESENTATION_SIZE = 1000
 # Prefix for saving functions return values in locals
 RETURN_VALUES_DICT = '__pydevd_ret_val_dict'
+GENERATED_LEN_ATTR_NAME = 'len()'
 
 import os
 
diff --git a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_resolver.py b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_resolver.py
index 0bcb7962..9279f262 100644
--- a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_resolver.py
+++ b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_resolver.py
@@ -9,7 +9,7 @@ from os.path import basename
 
 from functools import partial
 from _pydevd_bundle.pydevd_constants import dict_iter_items, dict_keys, xrange, IS_PY36_OR_GREATER, \
-    MethodWrapperType, RETURN_VALUES_DICT, DebugInfoHolder, IS_PYPY
+    MethodWrapperType, RETURN_VALUES_DICT, DebugInfoHolder, IS_PYPY, GENERATED_LEN_ATTR_NAME
 from _pydevd_bundle.pydevd_safe_repr import SafeRepr
 
 # Note: 300 is already a lot to see in the outline (after that the user should really use the shell to get things)
@@ -223,7 +223,7 @@ class DictResolver:
     sort_keys = not IS_PY36_OR_GREATER
 
     def resolve(self, dict, key):
-        if key in ('__len__', TOO_LARGE_ATTR):
+        if key in (GENERATED_LEN_ATTR_NAME, TOO_LARGE_ATTR):
             return None
 
         if '(' not in key:
@@ -276,17 +276,17 @@ class DictResolver:
                 ret.append((TOO_LARGE_ATTR, TOO_LARGE_MSG, None))
                 break
 
-        ret.append(('__len__', len(dct), partial(_apply_evaluate_name, evaluate_name='len(%s)')))
         # in case the class extends built-in type and has some additional fields
         from_default_resolver = defaultResolver.get_contents_debug_adapter_protocol(dct, fmt)
 
         if from_default_resolver:
             ret = from_default_resolver + ret
 
-        if not self.sort_keys:
-            return ret
+        if self.sort_keys:
+            ret = sorted(ret, key=lambda tup: sorted_attributes_key(tup[0]))
 
-        return sorted(ret, key=lambda tup: sorted_attributes_key(tup[0]))
+        ret.append((GENERATED_LEN_ATTR_NAME, len(dct), partial(_apply_evaluate_name, evaluate_name='len(%s)')))
+        return ret
 
     def get_dictionary(self, dict):
         ret = self.init_dict()
@@ -304,7 +304,7 @@ class DictResolver:
         # in case if the class extends built-in type and has some additional fields
         additional_fields = defaultResolver.get_dictionary(dict)
         ret.update(additional_fields)
-        ret['__len__'] = len(dict)
+        ret[GENERATED_LEN_ATTR_NAME] = len(dict)
         return ret
 
 
@@ -322,7 +322,7 @@ class TupleResolver:  # to enumerate tuples and lists
             @param var: that's the original attribute
             @param attribute: that's the key passed in the dict (as a string)
         '''
-        if attribute in ('__len__', TOO_LARGE_ATTR):
+        if attribute in (GENERATED_LEN_ATTR_NAME, TOO_LARGE_ATTR):
             return None
         try:
             return var[int(attribute)]
@@ -353,11 +353,12 @@ class TupleResolver:  # to enumerate tuples and lists
                 ret.append((TOO_LARGE_ATTR, TOO_LARGE_MSG, None))
                 break
 
-        ret.append(('__len__', len(lst), partial(_apply_evaluate_name, evaluate_name='len(%s)')))
         # Needed in case the class extends the built-in type and has some additional fields.
         from_default_resolver = defaultResolver.get_contents_debug_adapter_protocol(lst, fmt=fmt)
         if from_default_resolver:
             ret = from_default_resolver + ret
+
+        ret.append((GENERATED_LEN_ATTR_NAME, len(lst), partial(_apply_evaluate_name, evaluate_name='len(%s)')))
         return ret
 
     def get_dictionary(self, var, fmt={}):
@@ -378,7 +379,7 @@ class TupleResolver:  # to enumerate tuples and lists
         # in case if the class extends built-in type and has some additional fields
         additional_fields = defaultResolver.get_dictionary(var)
         d.update(additional_fields)
-        d['__len__'] = len(var)
+        d[GENERATED_LEN_ATTR_NAME] = len(var)
         return d
 
 
@@ -400,15 +401,15 @@ class SetResolver:
                 ret.append((TOO_LARGE_ATTR, TOO_LARGE_MSG, None))
                 break
 
-        ret.append(('__len__', len(obj), partial(_apply_evaluate_name, evaluate_name='len(%s)')))
         # Needed in case the class extends the built-in type and has some additional fields.
         from_default_resolver = defaultResolver.get_contents_debug_adapter_protocol(obj, fmt=fmt)
         if from_default_resolver:
             ret = from_default_resolver + ret
+        ret.append((GENERATED_LEN_ATTR_NAME, len(obj), partial(_apply_evaluate_name, evaluate_name='len(%s)')))
         return ret
 
     def resolve(self, var, attribute):
-        if attribute in ('__len__', TOO_LARGE_ATTR):
+        if attribute in (GENERATED_LEN_ATTR_NAME, TOO_LARGE_ATTR):
             return None
 
         try:
@@ -434,7 +435,7 @@ class SetResolver:
         # in case if the class extends built-in type and has some additional fields
         additional_fields = defaultResolver.get_dictionary(var)
         d.update(additional_fields)
-        d['__len__'] = len(var)
+        d[GENERATED_LEN_ATTR_NAME] = len(var)
         return d
 
     def change_var_from_name(self, container, name, new_value):
@@ -490,7 +491,7 @@ class JyArrayResolver:
     '''
 
     def resolve(self, var, attribute):
-        if attribute == '__len__':
+        if attribute == GENERATED_LEN_ATTR_NAME:
             return None
         return var[int(attribute)]
 
@@ -500,7 +501,7 @@ class JyArrayResolver:
         for i in xrange(len(obj)):
             ret[ i ] = obj[i]
 
-        ret['__len__'] = len(obj)
+        ret[GENERATED_LEN_ATTR_NAME] = len(obj)
         return ret
 
 
@@ -510,7 +511,7 @@ class JyArrayResolver:
 class MultiValueDictResolver(DictResolver):
 
     def resolve(self, dict, key):
-        if key in ('__len__', TOO_LARGE_ATTR):
+        if key in (GENERATED_LEN_ATTR_NAME, TOO_LARGE_ATTR):
             return None
 
         # ok, we have to iterate over the items to find the one that matches the id, because that's the only way
@@ -660,8 +661,7 @@ def get_var_scope(attr_name, attr_value, evaluate_name, handle_return_values):
     if handle_return_values and attr_name == RETURN_VALUES_DICT:
         return ''
 
-    elif attr_name == '__len__' and evaluate_name != '.__len__':
-        # Treat the __len__ we generate internally separate from the __len__ function
+    elif attr_name == GENERATED_LEN_ATTR_NAME:
         return ''
 
     if attr_name.startswith('__') and attr_name.endswith('__'):
diff --git a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_suspended_frames.py b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_suspended_frames.py
index 6271a204..6edbed9a 100644
--- a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_suspended_frames.py
+++ b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_suspended_frames.py
@@ -2,7 +2,7 @@ from contextlib import contextmanager
 import sys
 
 from _pydevd_bundle.pydevd_constants import get_frame, dict_items, RETURN_VALUES_DICT, \
-    dict_iter_items, ForkSafeLock
+    dict_iter_items, ForkSafeLock, GENERATED_LEN_ATTR_NAME
 from _pydevd_bundle.pydevd_xml import get_variable_details, get_type
 from _pydev_bundle.pydev_override import overrides
 from _pydevd_bundle.pydevd_resolver import sorted_attributes_key, TOO_LARGE_ATTR, get_var_scope
@@ -61,7 +61,7 @@ class _AbstractVariable(object):
             attributes.append('readOnly')
             name = '(return) %s' % (name,)
 
-        elif name in (TOO_LARGE_ATTR, '__len__'):
+        elif name in (TOO_LARGE_ATTR, GENERATED_LEN_ATTR_NAME):
             attributes.append('readOnly')
 
         var_data = {
diff --git a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_utils.py b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_utils.py
index e9a1ffe9..725dacda 100644
--- a/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_utils.py
+++ b/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_utils.py
@@ -11,7 +11,7 @@ except:
 import inspect
 import sys
 from _pydevd_bundle.pydevd_constants import IS_PY3K, USE_CUSTOM_SYS_CURRENT_FRAMES, IS_PYPY, SUPPORT_GEVENT, \
-    GEVENT_SUPPORT_NOT_SET_MSG
+    GEVENT_SUPPORT_NOT_SET_MSG, GENERATED_LEN_ATTR_NAME
 from _pydev_imps._pydev_saved_modules import threading
 
 
@@ -76,11 +76,11 @@ def to_number(x):
 
 
 def compare_object_attrs_key(x):
-    if '__len__' == x:
+    if GENERATED_LEN_ATTR_NAME == x:
         as_number = to_number(x)
         if as_number is None:
             as_number = 99999999
-        # __len__ should appear after other attributes in a list.
+        # len() should appear after other attributes in a list.
         return (1, as_number)
     else:
         return (-1, to_string(x))
diff --git a/src/debugpy/_vendored/pydevd/tests_python/test_debugger_json.py b/src/debugpy/_vendored/pydevd/tests_python/test_debugger_json.py
index 56e4f059..583fd2f7 100644
--- a/src/debugpy/_vendored/pydevd/tests_python/test_debugger_json.py
+++ b/src/debugpy/_vendored/pydevd/tests_python/test_debugger_json.py
@@ -17,7 +17,7 @@ from _pydevd_bundle._debug_adapter.pydevd_schema import (ThreadEvent, ModuleEven
 from _pydevd_bundle.pydevd_comm_constants import file_system_encoding
 from _pydevd_bundle.pydevd_constants import (int_types, IS_64BIT_PROCESS,
     PY_VERSION_STR, PY_IMPL_VERSION_STR, PY_IMPL_NAME, IS_PY36_OR_GREATER, IS_PY39_OR_GREATER,
-    IS_PY37_OR_GREATER, IS_PYPY)
+    IS_PY37_OR_GREATER, IS_PYPY, GENERATED_LEN_ATTR_NAME)
 from tests_python import debugger_unittest
 from tests_python.debug_constants import TEST_CHERRYPY, IS_PY2, TEST_DJANGO, TEST_FLASK, IS_PY26, \
     IS_PY27, IS_CPYTHON, TEST_GEVENT
@@ -1223,7 +1223,7 @@ def test_dict_ordered(case_setup):
 
         variables_response = json_facade.get_variables_response(ref)
         assert [(d['name'], d['value']) for d in variables_response.body.variables if (not d['name'].startswith('_OrderedDict')) and (d['name'] not in DAPGrouper.SCOPES_SORTED)] == [
-            ('4', "'first'"), ('3', "'second'"), ('2', "'last'"), ('__len__', '3')]
+            ('4', "'first'"), ('3', "'second'"), ('2', "'last'"), (GENERATED_LEN_ATTR_NAME, '3')]
 
         json_facade.write_continue()
         writer.finished_ok = True
@@ -1276,7 +1276,7 @@ def test_stack_and_variables_dict(case_setup):
         assert check == [
             {'name': "'a'", 'value': '30', 'type': 'int', 'evaluateName': "variable_for_test_3['a']", 'variablesReference': 0 },
             {'name': "'b'", 'value': '20', 'type': 'int', 'evaluateName': "variable_for_test_3['b']", 'variablesReference': 0},
-            {'name': '__len__', 'value': '2', 'type': 'int', 'evaluateName': 'len(variable_for_test_3)', 'variablesReference': 0, 'presentationHint': {'attributes': ['readOnly']}}
+            {'name': GENERATED_LEN_ATTR_NAME, 'value': '2', 'type': 'int', 'evaluateName': 'len(variable_for_test_3)', 'variablesReference': 0, 'presentationHint': {'attributes': ['readOnly']}}
         ]
 
         json_facade.write_continue()
@@ -1480,7 +1480,7 @@ def test_stack_and_variables_set_and_list(case_setup):
             u'variablesReference': 0,
         },
         {
-            u'name': u'__len__',
+            u'name': GENERATED_LEN_ATTR_NAME,
             u'type': u'int',
             u'value': u'2',
             u'evaluateName': u'len(variable_for_test_1)',
@@ -1683,7 +1683,7 @@ def test_evaluate_variable_references(case_setup):
                 'variablesReference': 0,
             },
             {
-                'name': '__len__',
+                'name': GENERATED_LEN_ATTR_NAME,
                 'type': 'int',
                 'value': '1',
                 'presentationHint': {'attributes': ['readOnly']},
diff --git a/src/debugpy/_vendored/pydevd/tests_python/test_resolvers.py b/src/debugpy/_vendored/pydevd/tests_python/test_resolvers.py
index 35fb7fea..033012e2 100644
--- a/src/debugpy/_vendored/pydevd/tests_python/test_resolvers.py
+++ b/src/debugpy/_vendored/pydevd/tests_python/test_resolvers.py
@@ -1,5 +1,5 @@
 from tests_python.debug_constants import IS_PY2
-from _pydevd_bundle.pydevd_constants import IS_PY36_OR_GREATER
+from _pydevd_bundle.pydevd_constants import IS_PY36_OR_GREATER, GENERATED_LEN_ATTR_NAME
 
 
 def check_len_entry(len_entry, first_2_params):
@@ -14,7 +14,7 @@ def test_dict_resolver():
     dct = {(1, 2): 2, u'22': 22}
     contents_debug_adapter_protocol = clear_contents_debug_adapter_protocol(dict_resolver.get_contents_debug_adapter_protocol(dct))
     len_entry = contents_debug_adapter_protocol.pop(-1)
-    check_len_entry(len_entry, ('__len__', 2))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 2))
     if IS_PY36_OR_GREATER:
         assert contents_debug_adapter_protocol == [
             ('(1, 2)', 2, '[(1, 2)]'), ("'22'", 22, "['22']")]
@@ -34,7 +34,7 @@ def test_dict_resolver_hex():
     contents_debug_adapter_protocol = clear_contents_debug_adapter_protocol(
         dict_resolver.get_contents_debug_adapter_protocol(dct, fmt={'hex': True}))
     len_entry = contents_debug_adapter_protocol.pop(-1)
-    check_len_entry(len_entry, ('__len__', 1))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 1))
     assert contents_debug_adapter_protocol == [
         ('(0x1, 0xa, 0x64)', (10000, 100000, 100000), '[(1, 10, 100)]'), ]
 
@@ -166,12 +166,6 @@ def test_django_forms_resolver():
 def clear_contents_debug_adapter_protocol(contents_debug_adapter_protocol):
     lst = []
     for x in contents_debug_adapter_protocol:
-        if x[0] == '__len__':
-            if x[2] == '.__len__':
-                # i.e.: remove a builtin __len__ method, but not the __len__ we add with the length.
-                continue
-            lst.append(x)
-
         if not x[0].startswith('__'):
 
             if '<built-in method' in str(x[1]) or '<method-wrapper' in str(x[1]) or '<bound method' in str(x[1]):
@@ -185,8 +179,6 @@ def clear_contents_debug_adapter_protocol(contents_debug_adapter_protocol):
 def clear_contents_dictionary(dictionary):
     dictionary = dictionary.copy()
     for key in list(dictionary):
-        if key == '__len__':
-            continue
         if key.startswith('__') or key in ('count', 'index'):
             del dictionary[key]
     return dictionary
@@ -213,7 +205,7 @@ def test_tuple_resolver():
         ('09', 9, '[9]'),
         ('10', 10, '[10]'),
     ]
-    check_len_entry(len_entry, ('__len__', 11))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 11))
 
     assert clear_contents_dictionary(tuple_resolver.get_dictionary(lst)) == {
         '00': 0,
@@ -227,7 +219,7 @@ def test_tuple_resolver():
         '08': 8,
         '09': 9,
         '10': 10,
-        '__len__': 11
+        GENERATED_LEN_ATTR_NAME: 11
     }
 
     lst = tuple(range(17))
@@ -253,7 +245,7 @@ def test_tuple_resolver():
         ('0x0f', 15, '[15]'),
         ('0x10', 16, '[16]'),
     ]
-    check_len_entry(len_entry, ('__len__', 17))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 17))
 
     assert clear_contents_dictionary(tuple_resolver.get_dictionary(lst, fmt=fmt)) == {
         '0x00': 0,
@@ -273,7 +265,7 @@ def test_tuple_resolver():
         '0x0e': 14,
         '0x0f': 15,
         '0x10': 16,
-        '__len__': 17
+        GENERATED_LEN_ATTR_NAME: 17
     }
 
     lst = tuple(range(10))
@@ -291,7 +283,7 @@ def test_tuple_resolver():
         ('8', 8, '[8]'),
         ('9', 9, '[9]'),
     ]
-    check_len_entry(len_entry, ('__len__', 10))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 10))
 
     assert clear_contents_dictionary(tuple_resolver.get_dictionary(lst)) == {
         '0': 0,
@@ -304,7 +296,7 @@ def test_tuple_resolver():
         '7': 7,
         '8': 8,
         '9': 9,
-        '__len__': 10
+        GENERATED_LEN_ATTR_NAME: 10
     }
 
     contents_debug_adapter_protocol = clear_contents_debug_adapter_protocol(tuple_resolver.get_contents_debug_adapter_protocol(lst, fmt=fmt))
@@ -321,7 +313,7 @@ def test_tuple_resolver():
         ('0x8', 8, '[8]'),
         ('0x9', 9, '[9]'),
     ]
-    check_len_entry(len_entry, ('__len__', 10))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 10))
 
     assert clear_contents_dictionary(tuple_resolver.get_dictionary(lst, fmt=fmt)) == {
         '0x0': 0,
@@ -334,7 +326,7 @@ def test_tuple_resolver():
         '0x7': 7,
         '0x8': 8,
         '0x9': 9,
-        '__len__': 10
+        GENERATED_LEN_ATTR_NAME: 10
     }
 
 
@@ -349,6 +341,6 @@ def test_tuple_resolver_mixed():
     my_tuple.some_value = 10
     contents_debug_adapter_protocol = clear_contents_debug_adapter_protocol(tuple_resolver.get_contents_debug_adapter_protocol(my_tuple))
     len_entry = contents_debug_adapter_protocol.pop(-1)
-    check_len_entry(len_entry, ('__len__', 2))
+    check_len_entry(len_entry, (GENERATED_LEN_ATTR_NAME, 2))
     assert contents_debug_adapter_protocol == [
         ('some_value', 10, '.some_value'), ('0', 1, '[0]'), ('1', 2, '[1]'), ]
diff --git a/src/debugpy/_vendored/pydevd/tests_python/test_suspended_frames_manager.py b/src/debugpy/_vendored/pydevd/tests_python/test_suspended_frames_manager.py
index ea4ba104..6c89b17b 100644
--- a/src/debugpy/_vendored/pydevd/tests_python/test_suspended_frames_manager.py
+++ b/src/debugpy/_vendored/pydevd/tests_python/test_suspended_frames_manager.py
@@ -1,5 +1,5 @@
 import sys
-from _pydevd_bundle.pydevd_constants import int_types
+from _pydevd_bundle.pydevd_constants import int_types, GENERATED_LEN_ATTR_NAME
 from _pydevd_bundle.pydevd_resolver import MAX_ITEMS_TO_HANDLE, TOO_LARGE_ATTR
 from _pydevd_bundle import pydevd_frame_utils
 
@@ -68,7 +68,7 @@ def test_suspended_frames_manager():
         as_dict = (dict([x.get_name(), x.get_var_data()] for x in children_vars if x.get_name() not in DAPGrouper.SCOPES_SORTED))
         assert as_dict == {
             '0': {'name': '0', 'value': '1', 'type': 'int', 'evaluateName': 'var2[0]', 'variablesReference': 0 },
-            '__len__': {'name': '__len__', 'value': '1', 'type': 'int', 'evaluateName': 'len(var2)', 'variablesReference': 0, 'presentationHint': {'attributes': ['readOnly']}, },
+            GENERATED_LEN_ATTR_NAME: {'name': GENERATED_LEN_ATTR_NAME, 'value': '1', 'type': 'int', 'evaluateName': 'len(var2)', 'variablesReference': 0, 'presentationHint': {'attributes': ['readOnly']}, },
         }
 
         var3 = dict((x.get_name(), x) for x in variable.get_children_variables())['var3']
@@ -78,7 +78,7 @@ def test_suspended_frames_manager():
 
         check_vars_dict_expected(as_dict, {
             '33': {'name': '33', 'value': "[1]", 'type': 'list', 'evaluateName': 'var3[33]'},
-            '__len__': {'name': '__len__', 'value': '1', 'type': 'int', 'evaluateName': 'len(var3)', 'variablesReference': 0, 'presentationHint': {'attributes': ['readOnly']}, }
+            GENERATED_LEN_ATTR_NAME: {'name': GENERATED_LEN_ATTR_NAME, 'value': '1', 'type': 'int', 'evaluateName': 'len(var3)', 'variablesReference': 0, 'presentationHint': {'attributes': ['readOnly']}, }
         })
 
 
@@ -132,11 +132,11 @@ def test_get_child_variables():
                     var_data = x.get_var_data()
                     assert 'readOnly' in var_data['presentationHint']['attributes']
                     found_too_large = True
-                elif x.name == '__len__':
+                elif x.name == GENERATED_LEN_ATTR_NAME:
                     found_len = True
 
             if not found_too_large:
                 raise AssertionError('Expected to find variable named: %s' % (TOO_LARGE_ATTR,))
             if not found_len:
-                raise AssertionError('Expected to find variable named: __len__')
+                raise AssertionError('Expected to find variable named: len()')
 
diff --git a/tests/debug/config.py b/tests/debug/config.py
index d3464a01..da0364ea 100644
--- a/tests/debug/config.py
+++ b/tests/debug/config.py
@@ -69,7 +69,12 @@ class DebugConfig(collections.MutableMapping):
         "connect": (),
         # Attach by PID
         "processId": (),
-        "variablePresentation": {},
+        "variablePresentation": {
+            "special": "group",
+            "function": "group",
+            "class_": "group",
+            "protected": "inline",
+        },
     }
 
     def __init__(self, *args, **kwargs):
diff --git a/tests/debugpy/test_evaluate.py b/tests/debugpy/test_evaluate.py
index 7a41e0ad..936bd04c 100644
--- a/tests/debugpy/test_evaluate.py
+++ b/tests/debugpy/test_evaluate.py
@@ -102,7 +102,7 @@ def test_variables(pyfile, target, run):
                 {
                     "type": "int",
                     "value": "2",
-                    "name": "__len__",
+                    "name": "len()",
                     "evaluateName": "len(b)",
                     "variablesReference": 0,
                     "presentationHint": {"attributes": ["readOnly"]},
@@ -162,7 +162,7 @@ def test_variable_sort(pyfile, target, run):
             "__c_test",
         ]
 
-        special_vars_entry = [v for v in vars if v["name"] == "special variables"][0]
+        special_vars_entry, = (v for v in vars if v["name"] == "special variables")
         special_vars_variables = session.request(
             "variables",
             {"variablesReference": special_vars_entry["variablesReference"]},
@@ -179,14 +179,14 @@ def test_variable_sort(pyfile, target, run):
         )["variables"]
         var_names = [v["name"] for v in b_test_vars]
         if sys.version_info[:2] >= (3, 6):
-            # Note that the special __len__ we manually create is not added to special variables.
+            # Note that the special len() we manually create is not added to special variables.
             expected = [
                 "special variables",
                 "function variables",
                 "'spam'",
                 "'eggs'",
                 "'abcd'",
-                "__len__",
+                "len()",
             ]
         else:
             expected = [
@@ -195,7 +195,7 @@ def test_variable_sort(pyfile, target, run):
                 "'abcd'",
                 "'eggs'",
                 "'spam'",
-                "__len__",
+                "len()",
             ]
 
         assert var_names == expected
@@ -207,8 +207,8 @@ def test_variable_sort(pyfile, target, run):
                 "variables", {"variablesReference": c_test["variablesReference"]}
             )["variables"]
             var_names = [v["name"] for v in c_test_vars]
-            # Note that the special __len__ we manually create is not added to special variables.
-            expected = ["1", "2", "10", "__len__"]
+            # Note that the special len() we manually create is not added to special variables.
+            expected = ["1", "2", "10", "len()"]
 
             assert var_names == expected
 
@@ -417,7 +417,7 @@ def test_hex_numbers(pyfile, target, run):
             ),
             some.dict.containing(
                 {
-                    "name": "__len__",
+                    "name": "len()",
                     "value": "0x3",
                     "type": "int",
                     "evaluateName": "len(b)",
@@ -463,7 +463,7 @@ def test_hex_numbers(pyfile, target, run):
                 ),
                 some.dict.containing(
                     {
-                        "name": "__len__",
+                        "name": "len()",
                         "value": "0x3",
                         "type": "int",
                         "evaluateName": "len(c)",
@@ -504,7 +504,7 @@ def test_hex_numbers(pyfile, target, run):
                 ),
                 some.dict.containing(
                     {
-                        "name": "__len__",
+                        "name": "len()",
                         "value": "0x3",
                         "type": "int",
                         "evaluateName": "len(c)",
@@ -530,7 +530,7 @@ def test_hex_numbers(pyfile, target, run):
             ),
             some.dict.containing(
                 {
-                    "name": "__len__",
+                    "name": "len()",
                     "value": "0x1",
                     "type": "int",
                     "evaluateName": "len(d)",
@@ -578,7 +578,7 @@ def test_hex_numbers(pyfile, target, run):
             ),
             some.dict.containing(
                 {
-                    "name": "__len__",
+                    "name": "len()",
                     "value": "0x3",
                     "type": "int",
                     "evaluateName": "len(d[(1, 10, 100)])",