add explicit panic with help message and properly failing test

JoJoJet · Jul 8, 2024 · 215b906 · 215b906
1 parent 0ab9bec
commit 215b906
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Showing 4 changed files with 39 additions and 10 deletions.
diff --git a/proc-macro/src/lib.rs b/proc-macro/src/lib.rs
@@ -240,7 +240,7 @@ fn impl_trait_query(arg: TokenStream, item: TokenStream) -> Result<TokenStream2>
             #[inline]
             fn get_state(_: &#imports::Components) -> Option<Self::State> {
                 // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-                None
+                panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
             }
 
             #[inline]
@@ -341,7 +341,7 @@ fn impl_trait_query(arg: TokenStream, item: TokenStream) -> Result<TokenStream2>
             #[inline]
             fn get_state(_: &#imports::Components) -> Option<Self::State> {
                 // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-                None
+                panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
             }
 
             #[inline]

diff --git a/src/all.rs b/src/all.rs
@@ -552,7 +552,7 @@ unsafe impl<'a, Trait: ?Sized + TraitQuery> WorldQuery for All<&'a Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     #[inline]
@@ -673,7 +673,7 @@ unsafe impl<'a, Trait: ?Sized + TraitQuery> WorldQuery for All<&'a mut Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     #[inline]

diff --git a/src/one.rs b/src/one.rs
@@ -244,7 +244,7 @@ unsafe impl<'a, Trait: ?Sized + TraitQuery> WorldQuery for One<&'a Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     #[inline]
@@ -432,7 +432,7 @@ unsafe impl<'a, Trait: ?Sized + TraitQuery> WorldQuery for One<&'a mut Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     #[inline]
@@ -590,7 +590,7 @@ unsafe impl<Trait: ?Sized + TraitQuery> WorldQuery for OneAdded<Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     fn matches_component_set(
@@ -737,7 +737,7 @@ unsafe impl<Trait: ?Sized + TraitQuery> WorldQuery for OneChanged<Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     fn matches_component_set(
@@ -846,7 +846,7 @@ unsafe impl<Trait: ?Sized + TraitQuery> WorldQuery for WithOne<Trait> {
     #[inline]
     fn get_state(_: &Components) -> Option<Self::State> {
         // TODO: fix this https://github.com/bevyengine/bevy/issues/13798
-        None
+        panic!("transmuting and any other operations concerning the state of a query are currently broken and shouldn't be used. See https://github.com/JoJoJet/bevy-trait-query/issues/59");
     }
 
     #[inline]

diff --git a/src/tests.rs b/src/tests.rs
@@ -693,7 +693,7 @@ fn query_and_transmute_and_print(
 }
 
 #[test]
-fn transmute_panics() {
+fn transmute_doesnt_panic_if_no_trait_touched() {
     let mut world = World::new();
     world.init_resource::<Output>();
     world
@@ -712,3 +712,32 @@ fn transmute_panics() {
 
     assert_eq!(world.resource::<Output>().0, &["0v1", "2v1", "3v1"]);
 }
+
+fn query_and_transmute_and_print_panic(
+    mut people: Query<(Entity, One<&dyn Person>)>,
+    mut output: ResMut<Output>,
+) {
+    for person in people.transmute_lens::<One<&dyn Person>>().query().iter() {
+        output.0.push(person.name().to_string());
+    }
+}
+
+#[test]
+#[should_panic]
+fn transmute_panics_if_trait_touched() {
+    let mut world = World::new();
+    world.init_resource::<Output>();
+    world
+        .register_component_as::<dyn Person, Human>()
+        .register_component_as::<dyn Person, Dolphin>();
+
+    world.spawn(Human("Garbanzo".to_owned(), 7));
+    world.spawn((Human("Garbanzo".to_owned(), 7), Dolphin(47)));
+    world.spawn((Human("Garbanzo".to_owned(), 14), Fem));
+    world.spawn(Dolphin(27));
+
+    let mut schedule = Schedule::default();
+    schedule.add_systems(query_and_transmute_and_print_panic);
+
+    schedule.run(&mut world);
+}