Missing list of incomplete features

[Barry1]

Documentation

Within the CLI we have the command line switch --enable-incomplete-feature which expects a feature name to enable.
Until now I have not been able to find a list of possible (incomplete/under development) features, which I could enable over here.

Have I missed something?

[tmke8]

It's defined here, but you're right that it's not documented anywhere:

mypy/mypy/options.py

Lines 70 to 73 in 83660d0

	# Features that are currently incomplete/experimental
	TYPE_VAR_TUPLE: Final = "TypeVarTuple"
	UNPACK: Final = "Unpack"
	INCOMPLETE_FEATURES: Final = frozenset((TYPE_VAR_TUPLE, UNPACK))

[som-sama]

So, we have to go through the codebase to identify all of the features that can be enabled with the --enable-incomplete-feature switch if I am not wrong?

[intgr]

I also noticed that the enable_incomplete_feature settings key is not documented. But if I add enable_incomplete_feature = ["Unpack"] to my pyproject.toml, it seems to work as expected.

[JelleZijlstra]

I think this is somewhat intentional; incomplete features are experimental and incomplete and may be broken in some way, so we don't want to advertise them too much.

However, it should be fine to add a list to the documentation with a note that these features are experimental, we don't guarantee any form of backward compatibility, use at your own risk, etc.

[jgarte]

However, it should be fine to add a list to the documentation with a note that these features are experimental, we don't guarantee any form of backward compatibility, use at your own risk, etc.

I think the latter is a great idea. I'll add a TODO to look into this when I find the time otherwise feel free to pick up this issue and resolve it.

[intgr]

By the way, the enable_incomplete_feature setting is still undocumented.