allow map_type to be specified by macro consumers (#835)

Author: ahl

cargo-typify/src/lib.rs

@@ -1,4 +1,4 @@
-// Copyright 2024 Oxide Computer Company
+// Copyright 2025 Oxide Computer Company
 
 //! cargo command to generate Rust code from a JSON Schema.
 
@@ -156,7 +156,7 @@ pub fn convert(args: &CliArgs) -> Result<String> {
     }
 
     if let Some(map_type) = &args.map_type {
-        settings.with_map_type(map_type.clone());
+        settings.with_map_type(map_type.as_str());
     }
 
     if let Some(unknown_crates) = &args.unknown_crates {

typify-impl/src/lib.rs

@@ -267,34 +267,12 @@ impl std::fmt::Display for MapType {
     }
 }
 
-impl<'de> serde::Deserialize<'de> for MapType {
-    fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
-    where
-        D: serde::Deserializer<'de>,
-    {
-        let s = <&str>::deserialize(deserializer)?;
-        Ok(Self::new(s))
-    }
-}
-
-impl From<String> for MapType {
-    fn from(s: String) -> Self {
-        Self::new(&s)
-    }
-}
-
 impl From<&str> for MapType {
     fn from(s: &str) -> Self {
         Self::new(s)
     }
 }
 
-impl From<syn::Type> for MapType {
-    fn from(t: syn::Type) -> Self {
-        Self(t)
-    }
-}
-
 /// Settings that alter type generation.
 #[derive(Default, Debug, Clone)]
 pub struct TypeSpaceSettings {

typify-macro/src/lib.rs

@@ -1,4 +1,4 @@
-// Copyright 2024 Oxide Computer Company
+// Copyright 2025 Oxide Computer Company
 
 //! typify macro implementation.
 
@@ -84,7 +84,7 @@ struct MacroSettings {
     #[serde(default)]
     crates: HashMap<CrateName, MacroCrateSpec>,
     #[serde(default)]
-    map_type: MapType,
+    map_type: Option<ParseWrapper<syn::Type>>,
 
     #[serde(default)]
     patch: HashMap<ParseWrapper<syn::Ident>, MacroPatch>,
@@ -223,7 +223,9 @@ fn do_import_types(item: TokenStream) -> Result<TokenStream, syn::Error> {
         );
         settings.with_unknown_crates(unknown_crates);
 
-        settings.with_map_type(map_type);
+        if let Some(map_type) = map_type {
+            settings.with_map_type(MapType(map_type.into_inner()));
+        }
 
         (schema.into_inner(), settings)
     };
@@ -263,3 +265,25 @@ fn do_import_types(item: TokenStream) -> Result<TokenStream, syn::Error> {
 fn into_syn_err(e: typify_impl::Error, span: proc_macro2::Span) -> syn::Error {
     syn::Error::new(span, e.to_string())
 }
+
+#[cfg(test)]
+mod tests {
+    use quote::quote;
+
+    use crate::MacroSettings;
+
+    #[test]
+    fn test_settings() {
+        let item = quote! {
+            schema = "foo.json",
+            derives = [::foo::Foo, ::bar::Bar],
+            replace = {
+                Baz = ::baz::Baz,
+            },
+            struct_builder = true,
+            map_type = ::my::map::Type,
+        };
+
+        let MacroSettings { .. } = serde_tokenstream::from_tokenstream(&item.into()).unwrap();
+    }
+}

typify-test/build.rs

@@ -1,3 +1,5 @@
+// Copyright 2025 Oxide Computer Company
+
 use std::collections::{HashMap, HashSet};
 use std::{env, fs, path::Path};
 
@@ -153,7 +155,7 @@ fn main() {
 
     // Generate with a custom map type to validate requirements.
     let mut settings = TypeSpaceSettings::default();
-    settings.with_map_type("CustomMap".to_string());
+    settings.with_map_type("CustomMap");
     let mut type_space = TypeSpace::new(&settings);
 
     WithMap::add(&mut type_space);

typify/tests/schemas.rs

@@ -1,4 +1,4 @@
-// Copyright 2024 Oxide Computer Company
+// Copyright 2025 Oxide Computer Company
 
 use std::{error::Error, fs::File, io::BufReader};
 
@@ -30,7 +30,7 @@ fn test_custom_map() {
     validate_schema(
         "tests/schemas/maps.json".into(),
         "tests/schemas/maps_custom.rs".into(),
-        TypeSpaceSettings::default().with_map_type("std::collections::BTreeMap".to_string()),
+        TypeSpaceSettings::default().with_map_type("std::collections::BTreeMap"),
     )
     .unwrap();