feat[ux]: compile .vyi files

[sandbubbles]

What I did

Allowed compiling ".vyi" files with ast,annotated_ast,interface,external_interface,abi flags.
#4232

How I did it

How to verify it

Commit message

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Description for the changelog

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[charles-cooper]

looking good to me. @cyberthirst can you take a look?

[cyberthirst]

bit unrelated, but if an interface implements other interface and doesn't implement all the methods, we get the following exception:

vyper.exceptions.InterfaceViolation: Contract does not implement all interface functions: foobar()

Contract does not implement.. although it can be triggered via eg vyper -f abi i.vyi

[cyberthirst]

-f interface doesn't include Flags. is it intended?

[charles-cooper]

-f interface doesn't include Flags. is it intended?

Not intended. May be the order in which we merged flag and -f interfave PRs

[cyberthirst]

shouldn't -f interface be basically an identity when called on interface files?

import ITest2

implements: ITest2

def bar() -> uint256:
    ...

def foo() -> uint8:
    ...


def foobar() -> uint8:
    ...

outputs:

# Functions

@external
def bar() -> uint256:
    ...


@external
def foo() -> uint8:
    ...


@external
def foobar() -> uint8:
    ...

ie implements is lost in the translation

[cyberthirst]

shouldn't -f interface be basically an identity when called on interface files?

import ITest2

implements: ITest2

def bar() -> uint256:
    ...

def foo() -> uint8:
    ...


def foobar() -> uint8:
    ...

outputs:

# Functions

@external
def bar() -> uint256:
    ...


@external
def foo() -> uint8:
    ...


@external
def foobar() -> uint8:
    ...

ie implements is lost in the translation

also, if ITest2.vyi contains a struct (or flag), then those don't propagate for -f interface - not sure whether that's intentional

[cyberthirst]

would it make sense to use this here? https://github.com/vyperlang/vyper/pull/4290/files#diff-d428d4c971c9f7166899f6f2d3da5e17ca4478d8d371d803e735d6ee36b39d30R49

so we don't have to maintain the list on 2 places

[cyberthirst]

 vyper -f external_interface tests/custom/ITest.vyi

# External Interfaces
interface Itest:
    def bar() -> uint256: nonpayable
    def foo() -> uint8: nonpayable
    def foobar() -> uint8: nonpayable

name discrepancy - Itest vs ITest

[charles-cooper]

this looks ok to me. @cyberthirst what did we decide about the -f interface behavior here?