Iterate over PyQt enums and get string representation

In PySide I can get the dictionary with possible/allowed enumerator values and their string representations by using values attribute. For example: QtWidgets.QMessageBox.StandardButton.values.items(). How to achieve the same in PyQt4/PyQt5? Is that even possible? I have found nothing about this in the docs.

PySide/PySide2 have a built-in enum type (Shiboken.EnumType) which supports iteration over the names/values. It also supports a name attribute, which you can use to get the enumerator name directly from its value.

Unfortunately, all versions of PyQt earlier than PyQt6 do not provide similar support. PyQt6 enums are subclasses of Python's IntEnum (so do support the above features), but PyQt5 enums are just plain subclasses of int with no additional features. This means you will have to roll your own solution to work around this limitation. It's tempting to try to use the Meta-Object System for this, but many classes (such as the Qt namespace) don't provide access to the necessary staticMetaObject, so that approach could never lead to a workable solution.

A much simpler and more general solution would be to leverage Python's introspection support. This will require obtaining a reference to the namespace object where the enumeration is defined, so that its __dict__ can be searched for all the relevant enumerators. In general, this namespace object won't always be available locally, and its parent module very often won't even have been imported yet, but importlib can be used to resolve this issue efficiently. In addition, some namespaces are multi-level (e.g. QtGui.QTouchEvent.TouchPoint.InfoFlag), so that needs special handling as well.

A basic implementation might therefore look something like this:

from importlib import import_module

def enum_mapping(enum):
    ns = import_module(enum.__module__)
    for name in enum.__qualname__.split('.')[:-1]:
        ns = getattr(ns, name)
    mapping = {}
    for key, value in ns.__dict__.items():
        if isinstance(value, enum):
            mapping[key] = value
    return mapping

from PyQt5.QtGui import *
from PyQt5.QtWidgets import *

for enum in (
    QTouchEvent.TouchPoint.InfoFlag,
    QTableWidget.EditTrigger,
    QMessageBox.StandardButton,
    ):
    print(f'{enum.__qualname__}:')
    for key, value in enum_mapping(enum).items():
        print(f'  {key} = {value}')
    print()

Output:

QTouchEvent.TouchPoint.InfoFlag:
  Pen = 1
  Token = 2

QAbstractItemView.EditTrigger:
  AllEditTriggers = 31
  AnyKeyPressed = 16
  CurrentChanged = 1
  DoubleClicked = 2
  EditKeyPressed = 8
  NoEditTriggers = 0
  SelectedClicked = 4

QMessageBox.StandardButton:
  Abort = 262144
  Apply = 33554432
  ButtonMask = -769
  Cancel = 4194304
  Close = 2097152
  Default = 256
  Discard = 8388608
  Escape = 512
  FirstButton = 1024
  FlagMask = 768
  Help = 16777216
  Ignore = 1048576
  LastButton = 134217728
  No = 65536
  NoAll = 131072
  NoButton = 0
  NoToAll = 131072
  Ok = 1024
  Open = 8192
  Reset = 67108864
  RestoreDefaults = 134217728
  Retry = 524288
  Save = 2048
  SaveAll = 4096
  Yes = 16384
  YesAll = 32768
  YesToAll = 32768