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The problem I'm having is that thetype doesn't supportParamSpec, so I can't use that to enforceargs andkwargs, in the same way as asCallable. I'm not 100% sure whether this is correct, but isn't everytype aCallable, so in a sense thattype is a subtype ofCallable, so there should be a way to representtype in the same way as aCallable to obey Liskov?
For example, I'm trying to write an overload such that passing in atype will returnExpectType, while a generalCallable returnsExpectCallable:
fromcollections.abcimportCallableimporttyping_extensionsastP=t.ParamSpec("P")T_co=t.TypeVar("T_co",covariant=True)classExpectCallable(t.Generic[P,T_co]): ...classExpectType(ExpectCallable[P,T_co]): ...@t.overloaddefexpect(v:type[T_co],/,*args:P.args,**kwargs:P.kwargs)->ExpectType[P,T_co]: ...@t.overloaddefexpect(v:Callable[P,T_co],/,*args:P.args,**kwargs:P.kwargs)->ExpectCallable[P,T_co]: ...defexpect(v:type[T_co]|Callable[P,T_co],/,*args:P.args,**kwargs:P.kwargs)->ExpectType[P,T_co]|ExpectCallable[P,T_co]:returnExpectType()ifisinstance(v,type)elseExpectCallable()classA:def__init__(self,inp:str,/)->None: ...deffn(inp:str,/)->None: ...t.assert_type(expect(A),ExpectType[[],A])# Shouldn't be allowedt.assert_type(expect(fn,"inp"),ExpectCallable[[str],None])
As you can see thatt.assert_type(expect(A), ExpectType[[], A]) passes with no errors, even thoughA is suppose to take in astr argument. I'm expectingexpect(A) to require astr argument, similar to howexpect(fn, "inp") requires the second parameter"inp".
Note that I haven't used*args and**kwargs in the example for simplicity, but they are meant to be used inside of theExpect classes.
Maybe the simplest way is to add a new classTypeCallable that allows forTypeCallable[P, T] instead of modifyingtype, so the above example is achievable:
@t.overloaddefexpect(v:TypeCallable[P,T_co],/,*args:P.args,**kwargs:P.kwargs)->ExpectType[P,T_co]: ...@t.overloaddefexpect(v:Callable[P,T_co],/,*args:P.args,**kwargs:P.kwargs)->ExpectCallable[P,T_co]: ...defexpect(v:TypeCallable[P,T_co]|Callable[P,T_co],/,*args:P.args,**kwargs:P.kwargs)->ExpectType[P,T_co]|ExpectCallable[P,T_co]:returnExpectType()ifisinstance(v,type)elseExpectCallable()
Note that I think#1966 might also solve the above problem.