Improve schema naming for deriving on remote types

docs/_includes/examples/remote_derive.rs

@@ -16,6 +16,7 @@ use schemars::{schema_for, JsonSchema};
 // This is just a copy of the remote data structure that Schemars can use to
 // create a suitable JsonSchema impl.
 #[derive(JsonSchema)]
+#[serde(remote = "Duration")]
 pub struct DurationDef {
     pub secs: i64,
     pub nanos: i32,

docs/_includes/examples/remote_derive.schema.json

@@ -11,11 +11,11 @@
       "type": "string"
     },
     "wall_time": {
-      "$ref": "#/definitions/DurationDef"
+      "$ref": "#/definitions/Duration"
     }
   },
   "definitions": {
-    "DurationDef": {
+    "Duration": {
       "type": "object",
       "required": [
         "nanos",

schemars/examples/remote_derive.rs

@@ -16,6 +16,7 @@ use schemars::{schema_for, JsonSchema};
 // This is just a copy of the remote data structure that Schemars can use to
 // create a suitable JsonSchema impl.
 #[derive(JsonSchema)]
+#[serde(remote = "Duration")]
 pub struct DurationDef {
     pub secs: i64,
     pub nanos: i32,

schemars/examples/remote_derive.schema.json

@@ -11,11 +11,11 @@
       "type": "string"
     },
     "wall_time": {
-      "$ref": "#/definitions/DurationDef"
+      "$ref": "#/definitions/Duration"
     }
   },
   "definitions": {
-    "DurationDef": {
+    "Duration": {
       "type": "object",
       "required": [
         "nanos",

schemars/tests/expected/remote_derive.json

@@ -14,7 +14,7 @@
       "default": "0.000000000s",
       "allOf": [
         {
-          "$ref": "#/definitions/DurationDef"
+          "$ref": "#/definitions/Duration"
         }
       ]
     },
@@ -25,16 +25,16 @@
       },
       "allOf": [
         {
-          "$ref": "#/definitions/DurationDef"
+          "$ref": "#/definitions/Duration"
         }
       ]
     },
     "wall_time": {
-      "$ref": "#/definitions/DurationDef"
+      "$ref": "#/definitions/Duration"
     }
   },
   "definitions": {
-    "DurationDef": {
+    "Duration": {
       "type": "object",
       "required": [
         "nanos",

schemars/tests/expected/remote_derive_generic.json

@@ -10,7 +10,7 @@
   ],
   "properties": {
     "byte_or_bool2": {
-      "$ref": "#/definitions/OrDef_for_uint8_and_Boolean"
+      "$ref": "#/definitions/Or_for_uint8_and_Boolean"
     },
     "fake_map": {
       "type": "object",
@@ -22,14 +22,14 @@
       }
     },
     "s": {
-      "$ref": "#/definitions/StrDef"
+      "$ref": "#/definitions/Str"
     },
     "unit_or_t2": {
-      "$ref": "#/definitions/OrDef_for_Null_and_int32"
+      "$ref": "#/definitions/Or_for_Null_and_int32"
     }
   },
   "definitions": {
-    "OrDef_for_Null_and_int32": {
+    "Or_for_Null_and_int32": {
       "anyOf": [
         {
           "type": "null"
@@ -40,7 +40,7 @@
         }
       ]
     },
-    "OrDef_for_uint8_and_Boolean": {
+    "Or_for_uint8_and_Boolean": {
       "anyOf": [
         {
           "type": "integer",
@@ -52,7 +52,7 @@
         }
       ]
     },
-    "StrDef": {
+    "Str": {
       "type": "string"
     }
   }

schemars_derive/src/attr/schemars_to_serde.rs

@@ -20,6 +20,7 @@ static SERDE_KEYWORDS: &[&str] = &[
     "skip_serializing_if",
     "skip_deserializing",
     "flatten",
+    "remote",
     // Special cases - `with`/`serialize_with` are passed to serde but not copied from schemars attrs to serde attrs.
     // This is because we want to preserve any serde attribute's `serialize_with` value to determine whether the field's
     // default value should be serialized. We also check the `with` value on schemars/serde attrs e.g. to support deriving

schemars_derive/src/lib.rs

@@ -43,19 +43,22 @@ pub fn derive_json_schema(input: proc_macro::TokenStream) -> proc_macro::TokenSt
     let type_name = cont.ident;
     let type_params: Vec<_> = cont.generics.type_params().map(|ty| &ty.ident).collect();
 
-    let schema_base_name = cont.attrs.name().deserialize_name();
+    let mut schema_base_name = cont.attrs.name().deserialize_name();
+    let schema_is_renamed = type_name != schema_base_name;
+
+    if !schema_is_renamed {
+        if let Some(path) = cont.attrs.remote() {
+            if let Some(segment) = path.segments.last() {
+                schema_base_name = segment.ident.to_string();
+            }
+        }
+    }
+    
     let schema_name = if type_params.is_empty() {
         quote! {
             #schema_base_name.to_owned()
         }
-    } else if type_name == schema_base_name {
+    } else if schema_is_renamed {
-        let mut schema_name_fmt = schema_base_name;
-        schema_name_fmt.push_str("_for_{}");
-        schema_name_fmt.push_str(&"_and_{}".repeat(type_params.len() - 1));
-        quote! {
-            format!(#schema_name_fmt #(,#type_params::schema_name())*)
-        }
-    } else {
         let mut schema_name_fmt = schema_base_name;
         for tp in &type_params {
             schema_name_fmt.push_str(&format!("{{{}:.0}}", tp));
@@ -63,6 +66,13 @@ pub fn derive_json_schema(input: proc_macro::TokenStream) -> proc_macro::TokenSt
         quote! {
             format!(#schema_name_fmt #(,#type_params=#type_params::schema_name())*)
         }
+    } else {
+        let mut schema_name_fmt = schema_base_name;
+        schema_name_fmt.push_str("_for_{}");
+        schema_name_fmt.push_str(&"_and_{}".repeat(type_params.len() - 1));
+        quote! {
+            format!(#schema_name_fmt #(,#type_params::schema_name())*)
+        }
     };
 
     let (impl_generics, ty_generics, where_clause) = cont.generics.split_for_impl();