Type singular relationship properties as nullable

docs/CHANGELOG.md

@@ -521,6 +521,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 #### Laravel
 
+- **Singular relationships can be `null`.** Reading a `hasOne`, `belongsTo`, `morphOne`, or `hasOneThrough` relationship as a property, such as `$post->author`, now gives `?Author` rather than `Author`, as Laravel's own relation generics and Larastan type it, since the related row may not exist.
 - **Route groups in `bootstrap/app.php`.** Routes registered from the `then:` or `using:` callback of `withRouting()`, including route files grouped there under a name prefix, are now known by their full names and are no longer reported as unknown routes.
 - **Imported `#[Table]` and `#[Connection]` attributes.** A model's table and connection attributes are now read when the attribute is imported with `use`, not only when written fully qualified, in files open in the editor and in `analyze`. Contributed by @shuvroroy.
 - **Nullable columns stay nullable through a cast.** A model attribute cast to `boolean`, `integer`, a date, an enum or another cast that hands `null` back untouched is now nullable when its column is, and so is a nullable `updated_at` or other timestamp column. A null check on a nullable date column, the soft-delete column included, leaves the date class with all its members.

src/virtual_members/laravel/relationships.rs

@@ -309,7 +309,7 @@ pub(super) fn build_property_type(
     custom_collection: Option<&str>,
 ) -> Option<PhpType> {
     match kind {
-        RelationshipKind::Singular => related_type.cloned(),
+        RelationshipKind::Singular => related_type.cloned().map(PhpType::nullable),
         RelationshipKind::Collection => {
             let inner = related_type.cloned().unwrap_or_else(eloquent_model_type);
             let collection_class = custom_collection.unwrap_or(ELOQUENT_COLLECTION_FQN);

src/virtual_members/laravel/relationships_tests.rs

@@ -203,7 +203,7 @@ fn singular_with_related() {
             Some(&PhpType::named(atom("App\\Models\\Post"))),
             None
         ),
-        Some(PhpType::named(atom("App\\Models\\Post")))
+        Some(PhpType::nullable(PhpType::named(atom("App\\Models\\Post"))))
     );
 }
 
@@ -295,7 +295,7 @@ fn singular_ignores_custom_collection() {
             Some(&PhpType::named(atom("App\\Models\\Post"))),
             Some("App\\Collections\\PostCollection")
         ),
-        Some(PhpType::named(atom("App\\Models\\Post")))
+        Some(PhpType::nullable(PhpType::named(atom("App\\Models\\Post"))))
     );
 }
 

src/virtual_members/laravel/tests.rs

@@ -606,7 +606,7 @@ fn synthesizes_has_one_property() {
         .iter()
         .find(|p| p.name == "profile")
         .unwrap();
-    assert_eq!(rel_prop.type_hint_str().as_deref(), Some("Profile"));
+    assert_eq!(rel_prop.type_hint_str().as_deref(), Some("?Profile"));
 }
 
 #[test]
@@ -625,7 +625,7 @@ fn synthesizes_belongs_to_property() {
         .iter()
         .find(|p| p.name == "author")
         .unwrap();
-    assert_eq!(rel_prop.type_hint_str().as_deref(), Some("User"));
+    assert_eq!(rel_prop.type_hint_str().as_deref(), Some("?User"));
 }
 
 #[test]
@@ -965,7 +965,7 @@ fn provides_fqn_related_type_singular() {
         .unwrap();
     assert_eq!(
         rel_prop.type_hint_str().as_deref(),
-        Some("\\App\\Models\\Profile")
+        Some("?\\App\\Models\\Profile")
     );
 }