Fix support for lifetime bounds

Author: taiki-e

pin-project-internal/src/pin_project/derive.rs

@@ -540,10 +540,10 @@ impl Context {
                 .generics
                 .lifetimes()
                 .enumerate()
-                .map(|(i, l)| {
+                .map(|(i, LifetimeDef { lifetime, .. })| {
                     let field_ident = format_ident!("__lifetime{}", i);
                     quote! {
-                        #field_ident: &#l ()
+                        #field_ident: &#lifetime ()
                     }
                 })
                 .collect();

tests/pin_project.rs

@@ -272,12 +272,11 @@ fn trait_bounds_on_type_generics() {
 
     impl<T> Static for Struct7<T> {}
 
-    // TODO: support this
-    // #[pin_project]
-    // pub struct Struct8<'a, 'b: 'a> {
-    //     field1: &'a u8,
-    //     field2: &'b u8,
-    // }
+    #[pin_project]
+    pub struct Struct8<'a, 'b: 'a> {
+        field1: &'a u8,
+        field2: &'b u8,
+    }
 
     #[pin_project]
     pub struct TupleStruct<'a, T: ?Sized>(&'a mut T);