Add codegen for cw_schema

Author: aumetra

Cargo.lock

@@ -5,7 +5,10 @@ use owo_colors::{OwoColorize, Style};
 use proc_macro2::TokenStream;
 use quote::{format_ident, quote};
 use std::{
-    borrow::Cow, env, fmt::Display, io::{self, Write as _}
+    borrow::Cow,
+    env,
+    fmt::Display,
+    io::{self, Write as _},
 };
 use syn::{DataEnum, DataStruct, DataUnion, DeriveInput, Lit};
 
@@ -38,7 +41,10 @@ fn print_warning(title: impl Display, content: impl Display) -> io::Result<()> {
 
     write!(sink, "{}", "  = ".style(blue))?;
     write!(sink, "{}", "note: ".style(bold))?;
-    writeln!(sink, "set `{DISABLE_WARNINGS_VAR}=1` to silence this warning")?;
+    writeln!(
+        sink,
+        "set `{DISABLE_WARNINGS_VAR}=1` to silence this warning"
+    )?;
 
     Ok(())
 }

packages/cw-schema-derive/src/expand.rs

@@ -1,6 +1,19 @@
 use crate::{Node, NodeType, Schemaifier};
 use alloc::{borrow::Cow, string::String, vec, vec::Vec};
 
+impl Schemaifier for () {
+    fn visit_schema(visitor: &mut crate::SchemaVisitor) -> crate::DefinitionReference {
+        visitor.insert(
+            Self::id(),
+            Node {
+                name: Cow::Borrowed("Unit"),
+                description: None,
+                value: NodeType::Unit,
+            },
+        )
+    }
+}
+
 impl Schemaifier for String {
     fn visit_schema(visitor: &mut crate::SchemaVisitor) -> crate::DefinitionReference {
         visitor.insert(

packages/cw-schema/src/default_impls.rs

@@ -112,6 +112,7 @@ pub enum NodeType {
     Optional {
         inner: DefinitionReference,
     },
+    Unit,
 }
 
 #[skip_serializing_none]

packages/cw-schema/src/lib.rs

@@ -10,6 +10,7 @@ license = "Apache-2.0"
 [dependencies]
 proc-macro2 = "1"
 quote = "1"
+strum = { version = "0.26.3", features = ["derive"] }
 syn = { version = "2", features = ["extra-traits", "full", "printing"] }
 
 [lib]