From fde0f6224382e83511e4aba30a6fa1d06faf89a7 Mon Sep 17 00:00:00 2001
From: Jacob Phillips <jifalops@gmail.com>
Date: Sun, 24 Mar 2024 14:13:19 +0000
Subject: [PATCH] can parse labels

---
 example/src/person.rs |  2 +-
 lib/src/entity.rs     |  5 +++--
 macros/src/derive.rs  | 40 ++++++++++++++++++++++++----------------
 3 files changed, 28 insertions(+), 19 deletions(-)

diff --git a/example/src/person.rs b/example/src/person.rs
index 425d6d0..aa0cbf0 100644
--- a/example/src/person.rs
+++ b/example/src/person.rs
@@ -27,7 +27,7 @@ mod tests {
     #[test]
     fn person() {
         assert_eq!(Person::typename(), "Person2");
-        assert_eq!(Person::labels(), &["Person2, PersonExtraLabel"]);
+        assert_eq!(Person::labels(), &["Person2", "PersonExtraLabel"]);
         assert_eq!(
             Person::field_names(),
             [
diff --git a/lib/src/entity.rs b/lib/src/entity.rs
index 10af706..8a7e57d 100644
--- a/lib/src/entity.rs
+++ b/lib/src/entity.rs
@@ -55,10 +55,11 @@ pub trait FieldSet: TryFrom<Row> {
     /// Formatted like `typename() { as_query_fields() }`, or for a fieldless relationship, just `typename()`.
     fn to_query_obj(prefix: Option<&str>, mode: StampMode) -> String {
         let fields = Self::to_query_fields(prefix, mode);
+        let labels = Self::labels().join(":");
         if fields.is_empty() {
-            return Self::labels().join(":").to_owned();
+            return labels;
         }
-        format!("{} {{ {} }}", Self::typename(), fields)
+        format!("{} {{ {} }}", labels, fields)
     }
 }
 
diff --git a/macros/src/derive.rs b/macros/src/derive.rs
index ab92cf9..df4234e 100644
--- a/macros/src/derive.rs
+++ b/macros/src/derive.rs
@@ -6,7 +6,10 @@ pub use node::Node;
 pub use relation::Relation;
 
 use quote::{__private::TokenStream, quote, ToTokens};
-use syn::{Attribute, LitStr, Meta};
+use syn::{
+    parse::{Parse, ParseStream},
+    Attribute, LitStr, Meta, Result, Token,
+};
 
 #[cfg(feature = "serde")]
 pub fn derive_serde() -> TokenStream {
@@ -67,22 +70,10 @@ pub fn parse_labels_meta(meta: &Meta) -> Option<Vec<String>> {
         // Parse #[labels("Foo", "Bar")].
         Meta::List(list) => {
             if list.path.is_ident("labels") {
-                let mut labels = Vec::new();
-                if let Err(e) = list.parse_nested_meta(|meta| {
-                    let label = syn::parse2::<LitStr>(meta.path.into_token_stream())
-                        .map(|lit| lit.value())
-                        .unwrap();
-
-                    labels.push(label);
-                    // match meta.path.get_ident() {
-                    //     Some(ident) => labels.push(ident.to_string()),
-                    //     None => panic!("Expected a label."),
-                    // };
-                    Ok(())
-                }) {
-                    panic!("Expected a list of labels: {}", e);
+                match list.parse_args::<Labels>() {
+                    Ok(labels) => Some(labels.0),
+                    Err(e) => panic!("Expected a list of labels: {}", e),
                 }
-                Some(labels)
             } else {
                 None
             }
@@ -91,6 +82,23 @@ pub fn parse_labels_meta(meta: &Meta) -> Option<Vec<String>> {
     }
 }
 
+struct Labels(Vec<String>);
+
+impl Parse for Labels {
+    fn parse(input: ParseStream) -> syn::Result<Labels> {
+        let mut values = Vec::new();
+        while !input.is_empty() {
+            let lit_str = input.parse::<LitStr>()?;
+            values.push(lit_str.value());
+            if input.is_empty() {
+                break;
+            }
+            input.parse::<Token![,]>()?;
+        }
+        Ok(Labels(values))
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use syn::parse_quote;