From: Matt Corallo <git@bluematt.me>
Date: Mon, 30 May 2022 23:51:54 +0000 (+0000)
Subject: Include the `where` clause from a "real" type when mapping type aliases
X-Git-Url: http://git.bitcoin.ninja/index.cgi?p=ldk-c-bindings;a=commitdiff_plain;h=d20bd908efc5c74d31c61dfc39660b8c62588687

Include the `where` clause from a "real" type when mapping type aliases

ie if we have a
```
struct A<T: Deref> where T::Target: Trait {}
pub type B<T> = A<T>;
```

this includes the `where` clause so that we end up calling
`writeln_opaque` for `struct B<T: Deref> where T::Target: Trait {}`
instead of `struct B<T: Deref> {}`.
---

diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs
index 37b64a8..bdd65e2 100644
--- a/c-bindings-gen/src/main.rs
+++ b/c-bindings-gen/src/main.rs
@@ -1922,6 +1922,11 @@ fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &CrateTypes<'a>
 									type_resolver.crate_types.priv_structs.get(&real_ty).map(|r| *r)).unwrap();
 								let mut resolved_generics = t.generics.clone();
 
+								// Assume blindly that the bounds in the struct definition where
+								// clause matches any equivalent bounds on the type alias.
+								assert!(resolved_generics.where_clause.is_none());
+								resolved_generics.where_clause = real_generic_bounds.where_clause.clone();
+
 								if let syn::PathArguments::AngleBracketed(real_generics) = &p.path.segments.last().unwrap().arguments {
 									for (real_idx, real_param) in real_generics.args.iter().enumerate() {
 										if let syn::GenericArgument::Type(syn::Type::Path(real_param_path)) = real_param {