add an impl_typed_uuid_kinds macro with x-rust-type support

[sunshowers]

This PR adds a new function-style proc macro called impl_typed_uuid_kinds, with support for automatic replacement of UUID kinds in typify (and therefore progenitor).

A typical invocation is:

impl_typed_uuid_kinds! {
    settings = {
        schemars08 = {
            attrs = [#[cfg(feature = "schemars")]],
            rust_type = {
                crate = "my-crate",
                version = "*",
                path = "my_crate::types",
            },
        },
    },
    kinds = {
        User = {},
        Organization = {},
        Project = {},
    },
}

TODO:

(Updates to Progenitor are not necessary since the fixes are all in typify.)

• Update Crucible: update progenitor to 0.11.0 crucible#1762
• Update Propolis: update progenitor to 0.11.0 propolis#931
• Update Progenitor in Omicron (TODO)
• Test end to end

[sunshowers]

Got this working end to end in Omicron with this patch: https://gist.github.com/sunshowers/1484f8cfa249c44c1426728194a258b6

[ahl]

This is really beautiful.

[ahl]

Suggested change

	/// * A `FooKind` type that implements `TypedUuidKind`: `pub type FooKind {}`.
	/// * A `FooKind` type that implements `TypedUuidKind`: `pub enum FooKind {}`.

?

[sunshowers]

Thanks, fixed.

[ahl]

You might consider an example that demonstrates the snakiness of the casing e.g. BusinessUnit rather than Organization ("business_unit")

Is that PascalCasiness a constraint on the inputs or only a suggestion?

[sunshowers]

Good idea re demonstrating snakiness -- thanks.

It's not a hard constraint but Rust would warn you about non-idiomatic type definitions:

[ahl]

I haven't heard "uninhabited", but I have used "marker" I think in case that's a useful shibboleth?

[sunshowers]

"Uninhabited" is a pretty Haskell-like term I guess. I'll change this to "also known as marker or uninhabited enums".

[ahl]

may I request that you use an explicit version here? I worry about copy-pasta proliferation that "works" but might be the wrong thing.

Suggested change

	/// version = "*",
	/// version = "0.1.0",

[sunshowers]

Reasonable, though I'm wondering if we should document something like "if your list of kinds is append-only, consider using "*"". Probably too much detail for this documentation, though.

[ahl]

do you need this? or just here to be explicit?

[sunshowers]

Ah yeah I don't think this is necessary, removed.

[ahl]

do you want to make it clear that this is unstable? I might have considered making it doc = hidden

[sunshowers]

Yeah definitely should be hidden in docs.

[ahl]

I needed to reread this a couple of times to understand it. In particular this means a type alias e.g. pub type = TypedUuid; perhaps this would have been clearer to me:

Suggested change

	/// Returns an alias for `TypedUuid<Self>`, if one is defined.
	///
	/// The alias must be defined in the same module as `Self`. This alias is
	/// used by schemars integration to refer to `TypedUuid<Self>` if available.
	/// Returns a string that corresponds to a type alias for `TypedUuid<Self>`, if one is defined.
	///
	/// The type alias must be defined in the same module as `Self`. This function is
	/// used by the schemars integration to embed a reference to that alias in the schema.

Might it make sense to mention the macro here as well? While folks can certainly use this independent of the macro, it might be worth guiding them toward the easy / intended path.

[sunshowers]

Yeah, makes sense.