Use of typing.Self in __init__

[tpgillam]

Consider the following example:

import typing

class A:
    def __init__(self: typing.Self) -> None:
        pass

Pyright will flag a reportInvalidTypeVarUse over the use of Self here. However, by my reading of the recent specification, this (probably?) ought to be allowed:

https://github.com/python/typing/blob/b908de0205fb208cd2d74fe342ab33f28f35b71b/docs/spec/constructors.rst?plain=1#L206-L207

If the self parameter within the __init__ method is not annotated, type checkers should infer a type of Self.

I am curious about what the correct resolution is for the inconsistency!

Also, in practice I am guessing that the general consensus is to discourage explicit annotation of self in general? e.g. I note that Ruff's ANN01 rule is deprecated.

[erictraut]

Pyright should not emit a diagnostic in this case. I'm going to convert this to a bug report.

And yes, there is no need to annotate self in general. Its type is implicitly Self unless you want to override this default. Likewise, the cls parameter in a class method always has the implicit type type[Self] unless explicitly overridden.

[erictraut]

Here's a link to the bug report: #8532

[tpgillam]

Thanks very much for addressing this so quickly!