Use a whitelist of recognized integer reprs

dtolnay · Oct 30, 2023 · 748970b · 748970b
1 parent b466791
commit 748970b
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Showing 2 changed files with 14 additions and 8 deletions.
diff --git a/src/parse.rs b/src/parse.rs
@@ -86,10 +86,18 @@ impl Parse for Input {
         let mut repr = None;
         for attr in derive_input.attrs {
             if attr.path().is_ident("repr") {
-                if let Meta::List(_) = &attr.meta {
-                    let ty: Ident = attr.parse_args()?;
-                    repr = Some(ty);
-                    break;
+                if let Meta::List(meta) = &attr.meta {
+                    meta.parse_nested_meta(|meta| {
+                        const RECOGNIZED: &[&str] = &[
+                            "u8", "u16", "u32", "u64", "u128", "usize", "i8", "i16", "i32", "i64",
+                            "i128", "isize",
+                        ];
+                        if RECOGNIZED.iter().any(|int| meta.path.is_ident(int)) {
+                            repr = Some(meta.path.get_ident().unwrap().clone());
+                            return Ok(());
+                        }
+                        Err(meta.error("unsupported repr for serde_repr enum"))
+                    })?;
                 }
             }
         }

diff --git a/tests/ui/repr_c.stderr b/tests/ui/repr_c.stderr
@@ -1,7 +1,5 @@
-error[E0412]: cannot find type `C` in this scope
+error: unsupported repr for serde_repr enum
  --> tests/ui/repr_c.rs:4:8
   |
-3 | #[derive(Serialize_repr)]
-  |          -------------- similarly named type parameter `S` defined here
 4 | #[repr(C)]
-  |        ^ help: a type parameter with a similar name exists: `S`
+  |        ^