Optional[Type] is shown as Union[Type, NoneType]

[hhoppe]

In the doc I maintain, https://google.github.io/mediapy/, the functions have many typing attributes.
These generally look great in the pdoc3 output, except that Optional[Type] is replaced by the more confusing Union[Type, NoneType].
Perhaps it would be possible to recognize this pattern and somehow change it back?

[hhoppe]

Also, the return type -> None is shown using the lengthier -> NoneType.

[kernc]

except that Optional[Type] is replaced by the more confusing Union[Type, NoneType]

I'm afraid that's what the values are resolved as by typing internals:

>>> import typing
>>> def foo() -> typing.Optional[int]: pass
>>> typing.get_type_hints(foo)
{'return': typing.Union[int, NoneType]}

If you can think of a good matching/replacement scheme, this would be the place to override it:

pdoc/pdoc/__init__.py

Lines 1243 to 1258 in aef1917

	def _formatannotation(annot):
	"""
	Format annotation, properly handling NewType types
	>>> import typing
	>>> _formatannotation(typing.NewType('MyType', str))
	'MyType'
	"""
	module = getattr(annot, '__module__', '')
	is_newtype = (getattr(annot, '__qualname__', '').startswith('NewType.') and
	module == 'typing')
	if is_newtype:
	return annot.__name__
	if module.startswith('nptyping'): # GH-231
	return repr(annot)
	return inspect.formatannotation(annot)

[hhoppe]

Thanks for the pointers. Handling the general case looks difficult. It seems that inspect uses repr to create a string from an annotation, which can be arbitrarily nested. One could try to recognize the pattern(s) in the resulting string, but that would require a parser rather than a regular expression.