Extend class binding to store pk info

Summary: We collect the pk info in the binding layer. We want to propagate it to the class metadata layer so we expend the binding to handle that

Reviewed By: rchen152

Differential Revision: D85478307

fbshipit-source-id: 33634325bef53d30f5b808d1f18a872dd3f82c76

Author: migeed-z

pyrefly/lib/alt/solve.rs

@@ -284,6 +284,7 @@ impl<'a, Ans: LookupAnswer> AnswersSolver<'a, Ans> {
             decorators,
             is_new_type,
             pydantic_config_dict,
+            django_primary_key_field: _,
         } = binding;
         let metadata = match &self.get_idx(*k).0 {
             None => ClassMetadata::recursive(),

pyrefly/lib/binding/binding.rs

@@ -102,7 +102,7 @@ assert_words!(BindingAnnotation, 15);
 assert_words!(BindingClass, 23);
 assert_words!(BindingTParams, 10);
 assert_words!(BindingClassBaseType, 3);
-assert_words!(BindingClassMetadata, 8);
+assert_words!(BindingClassMetadata, 11);
 assert_bytes!(BindingClassMro, 4);
 assert_bytes!(BindingAbstractClassCheck, 4);
 assert_words!(BindingClassField, 21);
@@ -2035,6 +2035,9 @@ pub struct BindingClassMetadata {
     /// Is this a new type? True only for synthesized classes created from a `NewType` call.
     pub is_new_type: bool,
     pub pydantic_config_dict: PydanticConfigDict,
+    /// The name of the field that has primary_key=True, if any (for Django models).
+    /// Note that we calculate this field for all classes, but it is ignored unless the class is a django model.
+    pub django_primary_key_field: Option<Name>,
 }
 
 impl DisplayWith<Bindings> for BindingClassMetadata {

pyrefly/lib/binding/class.rs

@@ -345,6 +345,7 @@ impl<'a> BindingsBuilder<'a> {
                 decorators: decorators_with_ranges.clone().into_boxed_slice(),
                 is_new_type: false,
                 pydantic_config_dict,
+                django_primary_key_field: None,
             },
         );
         self.insert_binding_idx(
@@ -487,6 +488,7 @@ impl<'a> BindingsBuilder<'a> {
                 decorators: Box::new([]),
                 is_new_type,
                 pydantic_config_dict: PydanticConfigDict::default(),
+                django_primary_key_field: None,
             },
         );
         self.insert_binding_idx(

pyrefly/lib/report/binding_memory.rs

@@ -165,6 +165,7 @@ mod tests {
             decorators: Default::default(),
             is_new_type: false,
             pydantic_config_dict: PydanticConfigDict::default(),
+            django_primary_key_field: None,
         };
         assert_eq!(
             ReportKey::new(module, &v),