test: add test for self field access

crates/mun_hir/src/code_model/module.rs

@@ -1,4 +1,4 @@
-use super::{r#impl::Impl, Function, Package, Struct, TypeAlias};
+use super::{r#impl::Impl, AssocItem, Function, Package, Struct, TypeAlias};
 use crate::{
     ids::{ItemDefinitionId, ModuleId},
     primitive_type::PrimitiveType,
@@ -81,7 +81,7 @@ impl Module {
         let package_defs = db.package_defs(self.id.package);
         package_defs.add_diagnostics(db.upcast(), self.id.local_id, sink);
 
-        // Add diagnostics from impls
+        // Add diagnostics from inherent impls
         let inherent_impls = db.inherent_impls_in_package(self.id.package);
         inherent_impls.add_module_diagnostics(db, self.id.local_id, sink);
 
@@ -102,6 +102,15 @@ impl Module {
                 _ => (),
             }
         }
+
+        // Add diagnostics from impls
+        for item in self.impls(db) {
+            for associated_item in item.items(db) {
+                let AssocItem::Function(fun) = associated_item;
+
+                fun.diagnostics(db, sink);
+            }
+        }
     }
 
     /// Returns all the child modules of this module

crates/mun_hir/src/ty/tests.rs

@@ -673,6 +673,27 @@ fn infer_self_param() {
     ));
 }
 
+#[test]
+fn infer_self_field() {
+    insta::assert_snapshot!(infer(
+        r#"
+    struct Foo {
+        a: i32
+    }
+
+    impl Foo {
+        fn self_a(self) -> i32 {
+            self.a
+        }
+
+        fn self_b(self) -> i32 {
+            self.b  // error: attempted to access a non-existent field in a struct.
+        }
+    }
+    "#
+    ));
+}
+
 #[test]
 fn infer_basics() {
     insta::assert_snapshot!(infer(