The Great Debuggening (#632)

The Great Debuggening

crates/bevy_app/src/app.rs

@@ -80,5 +80,5 @@ impl App {
 }
 
 /// An event that indicates the app should exit. This will fully exit the app process.
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct AppExit;

crates/bevy_app/src/event.rs

@@ -83,7 +83,6 @@ fn map_instance_event<T>(event_instance: &EventInstance<T>) -> &T {
 }
 
 /// Reads events of type `T` in order and tracks which events have already been read.
-#[derive(Debug)]
 pub struct EventReader<T> {
     last_event_count: usize,
     _marker: PhantomData<T>,

crates/bevy_asset/src/assets.rs

@@ -8,6 +8,7 @@ use bevy_type_registry::RegisterType;
 use bevy_utils::HashMap;
 
 /// Events that happen on assets of type `T`
+#[derive(Debug)]
 pub enum AssetEvent<T: Resource> {
     Created { handle: Handle<T> },
     Modified { handle: Handle<T> },
@@ -15,6 +16,7 @@ pub enum AssetEvent<T: Resource> {
 }
 
 /// Stores Assets of a given type and tracks changes to them.
+#[derive(Debug)]
 pub struct Assets<T: Resource> {
     assets: HashMap<Handle<T>, T>,
     events: Events<AssetEvent<T>>,

crates/bevy_asset/src/loader.rs

@@ -33,6 +33,7 @@ pub trait AssetLoader<T>: Send + Sync + 'static {
 }
 
 /// The result of loading an asset of type `T`
+#[derive(Debug)]
 pub struct AssetResult<T: 'static> {
     pub result: Result<T, AssetLoadError>,
     pub handle: Handle<T>,
@@ -41,6 +42,7 @@ pub struct AssetResult<T: 'static> {
 }
 
 /// A channel to send and receive [AssetResult]s
+#[derive(Debug)]
 pub struct AssetChannel<T: 'static> {
     pub sender: Sender<AssetResult<T>>,
     pub receiver: Receiver<AssetResult<T>>,

crates/bevy_audio/src/audio_output.rs

@@ -3,7 +3,7 @@ use bevy_asset::{Assets, Handle};
 use bevy_ecs::Res;
 use parking_lot::RwLock;
 use rodio::{Device, Sink};
-use std::collections::VecDeque;
+use std::{collections::VecDeque, fmt};
 
 /// Used to play audio on the current "audio device"
 pub struct AudioOutput<P = AudioSource>
@@ -14,6 +14,17 @@ where
     queue: RwLock<VecDeque<Handle<P>>>,
 }
 
+impl<P> fmt::Debug for AudioOutput<P>
+where
+    P: Decodable,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("AudioOutput")
+            .field("queue", &self.queue)
+            .finish()
+    }
+}
+
 impl<P> Default for AudioOutput<P>
 where
     P: Decodable,

crates/bevy_audio/src/audio_source.rs

@@ -3,7 +3,7 @@ use bevy_asset::AssetLoader;
 use std::{io::Cursor, path::Path, sync::Arc};
 
 /// A source of audio data
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct AudioSource {
     pub bytes: Arc<[u8]>,
 }

crates/bevy_core/src/label.rs

@@ -52,7 +52,7 @@ impl Labels {
 }
 
 /// Maintains a mapping from [Entity](bevy_ecs::prelude::Entity) ids to entity labels and entity labels to [Entities](bevy_ecs::prelude::Entity).
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct EntityLabels {
     label_entities: HashMap<Cow<'static, str>, Vec<Entity>>,
     entity_labels: HashMap<Entity, HashSet<Cow<'static, str>>>,

crates/bevy_diagnostic/src/diagnostic.rs

@@ -103,7 +103,7 @@ impl Diagnostic {
 }
 
 /// A collection of [Diagnostic]s
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct Diagnostics {
     diagnostics: HashMap<DiagnosticId, Diagnostic>,
 }

crates/bevy_diagnostic/src/system_profiler.rs

@@ -15,7 +15,7 @@ struct SystemRunInfo {
     stop: Instant,
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 struct SystemProfiles {
     diagnostic_id: DiagnosticId,
     history: Vec<SystemRunInfo>,
@@ -23,7 +23,7 @@ struct SystemProfiles {
 }
 
 /// Profiles systems by recording their run duration as diagnostics.
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct SystemProfiler {
     system_profiles: Arc<RwLock<HashMap<Cow<'static, str>, SystemProfiles>>>,
 }

crates/bevy_ecs/hecs/src/entities.rs

@@ -322,6 +322,7 @@ impl Entities {
 }
 
 /// Reserves entities in a way that is usable in multi-threaded contexts.
+#[derive(Debug)]
 pub struct EntityReserver {
     entities: &'static Entities,
 }

crates/bevy_ecs/src/resource/resource_query.rs

@@ -13,6 +13,7 @@ use std::marker::PhantomData;
 
 /// A shared borrow of a Resource
 /// that will only return in a query if the Resource has been changed
+#[derive(Debug)]
 pub struct ChangedRes<'a, T: Resource> {
     value: &'a T,
 }
@@ -200,6 +201,7 @@ impl<'a, T: Resource> ResourceQuery for Res<'a, T> {
 }
 
 /// Fetches a shared resource reference
+#[derive(Debug)]
 pub struct FetchResourceRead<T>(NonNull<T>);
 
 impl<'a, T: Resource> FetchResource<'a> for FetchResourceRead<T> {
@@ -229,6 +231,7 @@ impl<'a, T: Resource> ResourceQuery for ChangedRes<'a, T> {
 }
 
 /// Fetches a shared resource reference
+#[derive(Debug)]
 pub struct FetchResourceChanged<T>(NonNull<T>);
 
 impl<'a, T: Resource> FetchResource<'a> for FetchResourceChanged<T> {
@@ -263,6 +266,7 @@ impl<'a, T: Resource> ResourceQuery for ResMut<'a, T> {
 }
 
 /// Fetches a unique resource reference
+#[derive(Debug)]
 pub struct FetchResourceWrite<T>(NonNull<T>);
 
 impl<'a, T: Resource> FetchResource<'a> for FetchResourceWrite<T> {
@@ -300,6 +304,7 @@ impl<'a, T: Resource + FromResources> ResourceQuery for Local<'a, T> {
 }
 
 /// Fetches a `Local<T>` resource reference
+#[derive(Debug)]
 pub struct FetchResourceLocalMut<T>(NonNull<T>);
 
 impl<'a, T: Resource + FromResources> FetchResource<'a> for FetchResourceLocalMut<T> {
@@ -385,8 +390,10 @@ macro_rules! tuple_impl {
 
 smaller_tuples_too!(tuple_impl, O, N, M, L, K, J, I, H, G, F, E, D, C, B, A);
 
+#[derive(Debug)]
 pub struct OrRes<T>(T);
 
+#[derive(Debug)]
 pub struct FetchResourceOr<T>(NonNull<T>);
 
 macro_rules! tuple_impl_or {

crates/bevy_ecs/src/resource/resources.rs

@@ -9,19 +9,21 @@ use std::ptr::NonNull;
 pub trait Resource: Send + Sync + 'static {}
 impl<T: Send + Sync + 'static> Resource for T {}
 
+#[derive(Debug)]
 pub(crate) struct ResourceData {
     archetype: Archetype,
     default_index: Option<usize>,
     system_id_to_archetype_index: HashMap<usize, usize>,
 }
 
+#[derive(Debug)]
 pub enum ResourceIndex {
     Global,
     System(SystemId),
 }
 
 /// A collection of resource instances identified by their type.
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct Resources {
     pub(crate) resource_data: HashMap<TypeId, ResourceData>,
 }

crates/bevy_ecs/src/schedule/schedule.rs

@@ -4,7 +4,7 @@ use crate::{
 };
 use bevy_hecs::World;
 use bevy_utils::{HashMap, HashSet};
-use std::borrow::Cow;
+use std::{borrow::Cow, fmt};
 
 /// An ordered collection of stages, which each contain an ordered list of [System]s.
 /// Schedules are essentially the "execution plan" for an App's systems.
@@ -18,6 +18,27 @@ pub struct Schedule {
     last_initialize_generation: usize,
 }
 
+impl fmt::Debug for Schedule {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln!(f, "Schedule {{")?;
+
+        let stages = self
+            .stage_order
+            .iter()
+            .map(|s| (s, self.stages[s].iter().map(|s| (s.name(), s.id()))));
+
+        for (stage, syss) in stages {
+            writeln!(f, "    Stage \"{}\"", stage)?;
+
+            for (name, id) in syss {
+                writeln!(f, "        System {{ name: \"{}\", id: {:?} }}", name, id)?;
+            }
+        }
+
+        writeln!(f, "}}")
+    }
+}
+
 impl Schedule {
     pub fn add_stage(&mut self, stage: impl Into<Cow<'static, str>>) {
         let stage: Cow<str> = stage.into();

crates/bevy_ecs/src/system/commands.rs

@@ -2,7 +2,7 @@ use super::SystemId;
 use crate::resource::{Resource, Resources};
 use bevy_hecs::{Bundle, Component, DynamicBundle, Entity, EntityReserver, World};
 use parking_lot::Mutex;
-use std::{marker::PhantomData, sync::Arc};
+use std::{fmt, marker::PhantomData, sync::Arc};
 
 /// A queued command to mutate the current [World] or [Resources]
 pub enum Command {
@@ -10,11 +10,27 @@ pub enum Command {
     WriteResources(Box<dyn ResourcesWriter>),
 }
 
+impl fmt::Debug for Command {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Command::WriteWorld(x) => f
+                .debug_tuple("WriteWorld")
+                .field(&(x.as_ref() as *const dyn WorldWriter))
+                .finish(),
+            Command::WriteResources(x) => f
+                .debug_tuple("WriteResources")
+                .field(&(x.as_ref() as *const dyn ResourcesWriter))
+                .finish(),
+        }
+    }
+}
+
 /// A [World] mutation
 pub trait WorldWriter: Send + Sync {
     fn write(self: Box<Self>, world: &mut World);
 }
 
+#[derive(Debug)]
 pub(crate) struct Spawn<T>
 where
     T: DynamicBundle + Send + Sync + 'static,
@@ -49,6 +65,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub(crate) struct Despawn {
     entity: Entity,
 }
@@ -76,6 +93,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub(crate) struct InsertOne<T>
 where
     T: Component,
@@ -93,6 +111,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub(crate) struct RemoveOne<T>
 where
     T: Component,
@@ -112,6 +131,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub(crate) struct Remove<T>
 where
     T: Bundle + Send + Sync + 'static,
@@ -143,6 +163,7 @@ impl<T: Resource> ResourcesWriter for InsertResource<T> {
     }
 }
 
+#[derive(Debug)]
 pub(crate) struct InsertLocalResource<T: Resource> {
     resource: T,
     system_id: SystemId,
@@ -154,7 +175,7 @@ impl<T: Resource> ResourcesWriter for InsertLocalResource<T> {
     }
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct CommandsInternal {
     pub commands: Vec<Command>,
     pub current_entity: Option<Entity>,
@@ -212,7 +233,7 @@ impl CommandsInternal {
 }
 
 /// A queue of [Command]s to run on the current [World] and [Resources]
-#[derive(Default, Clone)]
+#[derive(Debug, Default, Clone)]
 pub struct Commands {
     pub commands: Arc<Mutex<CommandsInternal>>,
 }

crates/bevy_ecs/src/system/into_system.rs

@@ -7,6 +7,7 @@ use crate::{
 use bevy_hecs::{Fetch, Query as HecsQuery, World};
 use std::borrow::Cow;
 
+#[derive(Debug)]
 pub(crate) struct SystemFn<State, F, ThreadLocalF, Init, SetArchetypeAccess>
 where
     F: FnMut(&World, &Resources, &ArchetypeAccess, &mut State) + Send + Sync,

crates/bevy_ecs/src/system/query.rs

@@ -4,7 +4,7 @@ use bevy_hecs::{
     Without, World,
 };
 use bevy_tasks::ParallelIterator;
-use std::marker::PhantomData;
+use std::{fmt, marker::PhantomData};
 
 /// Provides scoped access to a World according to a given [HecsQuery]
 #[derive(Debug)]
@@ -140,6 +140,17 @@ pub struct QueryBorrowChecked<'w, Q: HecsQuery> {
     _marker: PhantomData<Q>,
 }
 
+impl<'w, Q: HecsQuery> fmt::Debug for QueryBorrowChecked<'w, Q> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("QueryBorrowChecked")
+            .field("archetypes", &self.archetypes)
+            .field("archetype_access", self.archetype_access)
+            .field("borrowed", &self.borrowed)
+            .field("_marker", &self._marker)
+            .finish()
+    }
+}
+
 impl<'w, Q: HecsQuery> QueryBorrowChecked<'w, Q> {
     pub(crate) fn new(archetypes: &'w [Archetype], archetype_access: &'w ArchetypeAccess) -> Self {
         Self {
@@ -241,6 +252,19 @@ pub struct QueryIter<'q, 'w, Q: HecsQuery> {
     iter: Option<ChunkIter<Q>>,
 }
 
+impl<'q, 'w, Q: HecsQuery> fmt::Debug for QueryIter<'q, 'w, Q>
+where
+    Q::Fetch: fmt::Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("QueryIter")
+            .field("borrow", self.borrow)
+            .field("archetype_index", &self.archetype_index)
+            .field("iter", &self.iter)
+            .finish()
+    }
+}
+
 unsafe impl<'q, 'w, Q: HecsQuery> Send for QueryIter<'q, 'w, Q> {}
 unsafe impl<'q, 'w, Q: HecsQuery> Sync for QueryIter<'q, 'w, Q> {}
 
@@ -296,6 +320,18 @@ struct ChunkIter<Q: HecsQuery> {
     len: usize,
 }
 
+impl<Q: HecsQuery> fmt::Debug for ChunkIter<Q>
+where
+    Q::Fetch: fmt::Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("ChunkIter")
+            .field("fetch", &self.fetch)
+            .field("len", &self.len)
+            .finish()
+    }
+}
+
 impl<Q: HecsQuery> ChunkIter<Q> {
     #[inline]
     unsafe fn next<'a>(&mut self) -> Option<<Q::Fetch as Fetch<'a>>::Item> {
@@ -363,6 +399,18 @@ pub struct Batch<'q, Q: HecsQuery> {
     state: ChunkIter<Q>,
 }
 
+impl<'q, Q: HecsQuery> fmt::Debug for Batch<'q, Q>
+where
+    Q::Fetch: fmt::Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("Batch")
+            .field("_marker", &self._marker)
+            .field("state", &self.state)
+            .finish()
+    }
+}
+
 impl<'q, 'w, Q: HecsQuery> Iterator for Batch<'q, Q> {
     type Item = <Q::Fetch as Fetch<'q>>::Item;
 
@@ -375,6 +423,7 @@ impl<'q, 'w, Q: HecsQuery> Iterator for Batch<'q, Q> {
 unsafe impl<'q, Q: HecsQuery> Send for Batch<'q, Q> {}
 
 /// A borrow of a `World` sufficient to execute the query `Q` on a single entity
+#[derive(Debug)]
 pub struct QueryOneChecked<'a, Q: HecsQuery> {
     archetype: &'a Archetype,
     index: usize,

crates/bevy_ecs/src/world/world_builder.rs

@@ -15,6 +15,7 @@ impl WorldBuilderSource for World {
 }
 
 /// Modify a [World] using the builder pattern
+#[derive(Debug)]
 pub struct WorldBuilder<'a> {
     pub world: &'a mut World,
     pub current_entity: Option<Entity>,

crates/bevy_gilrs/src/gilrs_system.rs

@@ -6,10 +6,12 @@ use gilrs::{Button, EventType, Gilrs};
 use std::sync::{Arc, Mutex};
 
 // TODO: remove this if/when bevy_ecs supports thread local resources
+#[derive(Debug)]
 struct GilrsSendWrapper(Gilrs);
 
 unsafe impl Send for GilrsSendWrapper {}
 
+#[derive(Debug)]
 pub struct GilrsArcMutexWrapper(Arc<Mutex<GilrsSendWrapper>>);
 
 impl GilrsArcMutexWrapper {

crates/bevy_gltf/src/loader.rs

@@ -12,7 +12,7 @@ use thiserror::Error;
 /// Loads meshes from GLTF files into Mesh assets
 ///
 /// NOTE: eventually this will loading into Scenes instead of Meshes
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct GltfLoader;
 
 impl AssetLoader<Mesh> for GltfLoader {

crates/bevy_input/src/axis.rs

@@ -1,5 +1,6 @@
 use std::{collections::HashMap, hash::Hash};
 
+#[derive(Debug)]
 pub struct Axis<T> {
     axis_data: HashMap<T, f32>,
 }

crates/bevy_pbr/src/entity.rs

@@ -53,7 +53,7 @@ impl Default for PbrComponents {
 }
 
 /// A component bundle for "light" entities
-#[derive(Bundle, Default)]
+#[derive(Debug, Bundle, Default)]
 pub struct LightComponents {
     pub light: Light,
     pub transform: Transform,

crates/bevy_pbr/src/light.rs

@@ -8,7 +8,7 @@ use bevy_transform::components::GlobalTransform;
 use std::ops::Range;
 
 /// A point light
-#[derive(Properties)]
+#[derive(Debug, Properties)]
 pub struct Light {
     pub color: Color,
     pub fov: f32,
@@ -26,7 +26,7 @@ impl Default for Light {
 }
 
 #[repr(C)]
-#[derive(Clone, Copy)]
+#[derive(Debug, Clone, Copy)]
 pub(crate) struct LightRaw {
     pub proj: [[f32; 4]; 4],
     pub pos: [f32; 4],

crates/bevy_pbr/src/material.rs

@@ -2,7 +2,7 @@ use bevy_asset::{self, Handle};
 use bevy_render::{color::Color, renderer::RenderResources, shader::ShaderDefs, texture::Texture};
 
 /// A material with "standard" properties used in PBR lighting
-#[derive(RenderResources, ShaderDefs)]
+#[derive(Debug, RenderResources, ShaderDefs)]
 #[allow(clippy::manual_non_exhaustive)]
 pub struct StandardMaterial {
     pub albedo: Color,

crates/bevy_pbr/src/render_graph/lights_node.rs

@@ -14,7 +14,7 @@ use bevy_render::{
 use bevy_transform::prelude::*;
 
 /// A Render Graph [Node] that write light data from the ECS to GPU buffers
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct LightsNode {
     command_queue: CommandQueue,
     max_lights: usize,
@@ -43,7 +43,7 @@ impl Node for LightsNode {
 }
 
 #[repr(C)]
-#[derive(Clone, Copy)]
+#[derive(Debug, Clone, Copy)]
 struct LightCount {
     pub num_lights: [u32; 4],
 }
@@ -67,7 +67,7 @@ impl SystemNode for LightsNode {
 }
 
 /// Local "lights node system" state
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct LightsNodeSystemState {
     light_buffer: Option<BufferId>,
     staging_buffer: Option<BufferId>,

crates/bevy_property/src/dynamic_properties.rs

@@ -4,7 +4,7 @@ use crate::{
 };
 use bevy_utils::HashMap;
 use serde::de::DeserializeSeed;
-use std::{any::Any, borrow::Cow};
+use std::{any::Any, borrow::Cow, fmt};
 
 pub struct DynamicProperties {
     pub type_name: String,
@@ -14,6 +14,24 @@ pub struct DynamicProperties {
     pub property_type: PropertyType,
 }
 
+impl fmt::Debug for DynamicProperties {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let props = self
+            .props
+            .iter()
+            .map(|p| p.as_ref() as *const dyn Property)
+            .collect::<Vec<_>>();
+
+        f.debug_struct("DynamicProperties")
+            .field("type_name", &self.type_name)
+            .field("props", &props)
+            .field("prop_names", &self.prop_names)
+            .field("prop_indices", &self.prop_indices)
+            .field("property_type", &self.property_type)
+            .finish()
+    }
+}
+
 impl DynamicProperties {
     pub fn map() -> Self {
         DynamicProperties {

crates/bevy_property/src/property_serde.rs

@@ -25,6 +25,7 @@ impl<'a> Serializable<'a> {
         }
     }
 }
+
 pub struct PropertyValueSerializer<'a, T>
 where
     T: Property + Serialize,
@@ -277,6 +278,7 @@ impl<'a, 'de> DeserializeSeed<'de> for PropertyDeserializer<'a> {
         }
     }
 }
+
 pub struct SeqPropertyDeserializer<'a> {
     registry: &'a PropertyTypeRegistry,
 }

crates/bevy_property/src/type_registry.rs

@@ -1,8 +1,8 @@
 use crate::{DeserializeProperty, Property};
 use bevy_utils::{HashMap, HashSet};
-use std::any::TypeId;
+use std::{any::TypeId, fmt};
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct PropertyTypeRegistry {
     registrations: HashMap<String, PropertyTypeRegistration>,
     short_names: HashMap<String, String>,
@@ -72,6 +72,24 @@ pub struct PropertyTypeRegistration {
     pub name: &'static str,
 }
 
+impl fmt::Debug for PropertyTypeRegistration {
+    fn fmt<'a>(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("PropertyTypeRegistration")
+            .field("ty", &self.ty)
+            .field(
+                "deserialize_fn",
+                &(self.deserialize_fn
+                    as fn(
+                        deserializer: &'a mut dyn erased_serde::Deserializer<'a>,
+                        property_type_registry: &'a PropertyTypeRegistry,
+                    ) -> Result<Box<dyn Property>, erased_serde::Error>),
+            )
+            .field("short_name", &self.short_name)
+            .field("name", &self.name)
+            .finish()
+    }
+}
+
 impl PropertyTypeRegistration {
     pub fn of<T: Property + DeserializeProperty>() -> Self {
         let ty = TypeId::of::<T>();

crates/bevy_render/src/batch/batcher.rs

@@ -1,7 +1,7 @@
 use super::Batch;
 use bevy_utils::HashMap;
 use smallvec::{smallvec, SmallVec};
-use std::{borrow::Cow, hash::Hash};
+use std::{borrow::Cow, fmt, hash::Hash};
 
 // TODO: add sorting by primary / secondary handle to reduce rebinds of data
 
@@ -28,6 +28,7 @@ impl<TKey: Key> BatchKey<TKey> {
     }
 }
 
+#[derive(Debug)]
 pub struct BatcherKeyState<TKey: Key> {
     batch_key: Option<BatchKey<TKey>>,
     keys: SmallVec<[Option<TKey>; 2]>,
@@ -77,6 +78,28 @@ where
     pub key_count: usize,
 }
 
+impl<TKey: Key, TValue, TData> fmt::Debug for Batcher<TKey, TValue, TData>
+where
+    TKey: Key + fmt::Debug,
+    TValue: fmt::Debug,
+    TData: fmt::Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let is_index = self
+            .is_index
+            .iter()
+            .map(|f| f as *const for<'r> fn(&'r TKey) -> bool)
+            .collect::<Vec<_>>();
+
+        f.debug_struct("Batcher")
+            .field("batches", &self.batches)
+            .field("is_index", &is_index)
+            .field("key_states", &self.key_states)
+            .field("key_count", &self.key_count)
+            .finish()
+    }
+}
+
 impl<TKey, TValue, TData> Batcher<TKey, TValue, TData>
 where
     TKey: Key,

crates/bevy_render/src/camera/active_cameras.rs

@@ -2,7 +2,7 @@ use super::Camera;
 use bevy_ecs::{Entity, Query, ResMut};
 use bevy_utils::HashMap;
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct ActiveCameras {
     pub cameras: HashMap<String, Option<Entity>>,
 }

crates/bevy_render/src/draw.rs

@@ -50,7 +50,7 @@ pub enum RenderCommand {
 }
 
 /// A component that indicates how to draw an entity.
-#[derive(Properties, Clone)]
+#[derive(Debug, Properties, Clone)]
 pub struct Draw {
     pub is_visible: bool,
     pub is_transparent: bool,
@@ -123,6 +123,7 @@ pub enum DrawError {
     BufferAllocationFailure,
 }
 
+//#[derive(Debug)]
 pub struct DrawContext<'a> {
     pub pipelines: ResMut<'a, Assets<PipelineDescriptor>>,
     pub shaders: ResMut<'a, Assets<Shader>>,
@@ -151,6 +152,7 @@ impl<'a> ResourceQuery for DrawContext<'a> {
     type Fetch = FetchDrawContext;
 }
 
+#[derive(Debug)]
 pub struct FetchDrawContext;
 
 // TODO: derive this impl

crates/bevy_render/src/mesh/mesh.rs

@@ -181,6 +181,7 @@ pub mod shape {
     use hexasphere::Hexasphere;
 
     /// A cube.
+    #[derive(Debug)]
     pub struct Cube {
         /// Half the side length of the cube.
         pub size: f32,
@@ -259,6 +260,7 @@ pub mod shape {
     }
 
     /// A rectangle on the XY plane.
+    #[derive(Debug)]
     pub struct Quad {
         /// Full width and height of the rectangle.
         pub size: Vec2,
@@ -357,6 +359,7 @@ pub mod shape {
     }
 
     /// A square on the XZ plane.
+    #[derive(Debug)]
     pub struct Plane {
         /// The total side length of the square.
         pub size: f32,
@@ -397,6 +400,7 @@ pub mod shape {
     }
 
     /// A sphere made from a subdivided Icosahedron.
+    #[derive(Debug)]
     pub struct Icosphere {
         /// The radius of the sphere.
         pub radius: f32,

crates/bevy_render/src/mesh/vertex.rs

@@ -2,7 +2,7 @@ use crate::pipeline::AsVertexBufferDescriptor;
 use bevy_core::Byteable;
 
 #[repr(C)]
-#[derive(Clone, Copy, AsVertexBufferDescriptor)]
+#[derive(Debug, Clone, Copy, AsVertexBufferDescriptor)]
 #[as_crate(bevy_render)]
 pub struct Vertex {
     pub position: [f32; 3],

crates/bevy_render/src/pipeline/pipeline_compiler.rs

@@ -44,11 +44,13 @@ pub struct ShaderSpecialization {
     pub shader_defs: HashSet<String>,
 }
 
+#[derive(Debug)]
 struct SpecializedShader {
     shader: Handle<Shader>,
     specialization: ShaderSpecialization,
 }
 
+#[derive(Debug)]
 struct SpecializedPipeline {
     pipeline: Handle<PipelineDescriptor>,
     specialization: PipelineSpecialization,
@@ -60,7 +62,7 @@ pub struct DynamicBinding {
     pub binding: u32,
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct PipelineCompiler {
     specialized_shaders: HashMap<Handle<Shader>, Vec<SpecializedShader>>,
     specialized_pipelines: HashMap<Handle<PipelineDescriptor>, Vec<SpecializedPipeline>>,

crates/bevy_render/src/pipeline/render_pipelines.rs

@@ -9,7 +9,7 @@ use bevy_asset::{Assets, Handle};
 use bevy_ecs::{Query, Res, ResMut};
 use bevy_property::Properties;
 
-#[derive(Properties, Default, Clone)]
+#[derive(Debug, Properties, Default, Clone)]
 #[non_exhaustive]
 pub struct RenderPipeline {
     pub pipeline: Handle<PipelineDescriptor>,
@@ -35,7 +35,7 @@ impl RenderPipeline {
     }
 }
 
-#[derive(Properties, Clone)]
+#[derive(Debug, Properties, Clone)]
 pub struct RenderPipelines {
     pub pipelines: Vec<RenderPipeline>,
     #[property(ignore)]

crates/bevy_render/src/pipeline/vertex_buffer_descriptor.rs

@@ -46,7 +46,7 @@ pub struct VertexAttributeDescriptor {
     pub shader_location: u32,
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct VertexBufferDescriptors {
     pub descriptors: HashMap<String, VertexBufferDescriptor>,
 }

crates/bevy_render/src/render_graph/base.rs

@@ -17,6 +17,7 @@ use bevy_window::WindowId;
 #[derive(Default, Properties)]
 pub struct MainPass;
 
+#[derive(Debug)]
 pub struct Msaa {
     pub samples: u32,
 }
@@ -50,6 +51,7 @@ impl Msaa {
     }
 }
 
+#[derive(Debug)]
 pub struct BaseRenderGraphConfig {
     pub add_2d_camera: bool,
     pub add_3d_camera: bool,

crates/bevy_render/src/render_graph/command.rs

@@ -27,7 +27,7 @@ pub enum Command {
     FreeBuffer(BufferId),
 }
 
-#[derive(Default, Clone)]
+#[derive(Debug, Default, Clone)]
 pub struct CommandQueue {
     // TODO: this shouldn't really need a mutex. it just needs to be shared on whatever thread it's scheduled on
     queue: Arc<Mutex<Vec<Command>>>,

crates/bevy_render/src/render_graph/node.rs

@@ -40,6 +40,7 @@ pub trait SystemNode: Node {
     fn get_system(&self, commands: &mut Commands) -> Box<dyn System>;
 }
 
+#[derive(Debug)]
 pub struct Edges {
     pub id: NodeId,
     pub input_edges: Vec<Edge>,

crates/bevy_render/src/render_graph/nodes/camera_node.rs

@@ -12,6 +12,7 @@ use bevy_ecs::{Commands, IntoQuerySystem, Local, Query, Res, ResMut, Resources,
 use bevy_transform::prelude::*;
 use std::borrow::Cow;
 
+#[derive(Debug)]
 pub struct CameraNode {
     command_queue: CommandQueue,
     camera_name: Cow<'static, str>,
@@ -58,7 +59,7 @@ impl SystemNode for CameraNode {
     }
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct CameraNodeState {
     command_queue: CommandQueue,
     camera_name: Cow<'static, str>,

crates/bevy_render/src/render_graph/nodes/pass_node.rs

@@ -13,8 +13,9 @@ use crate::{
 };
 use bevy_asset::{Assets, Handle};
 use bevy_ecs::{HecsQuery, ReadOnlyFetch, Resources, World};
-use std::{marker::PhantomData, ops::Deref};
+use std::{fmt, marker::PhantomData, ops::Deref};
 
+#[derive(Debug)]
 struct CameraInfo {
     name: String,
     bind_group_id: Option<BindGroupId>,
@@ -32,6 +33,36 @@ pub struct PassNode<Q: HecsQuery> {
     _marker: PhantomData<Q>,
 }
 
+impl<Q: HecsQuery> fmt::Debug for PassNode<Q> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("PassNose")
+            .field("descriptor", &self.descriptor)
+            .field("inputs", &self.inputs)
+            .field("cameras", &self.cameras)
+            .field(
+                "color_attachment_input_indices",
+                &self.color_attachment_input_indices,
+            )
+            .field(
+                "color_resolve_target_indices",
+                &self.color_resolve_target_indices,
+            )
+            .field(
+                "depth_stencil_attachment_input_index",
+                &self.depth_stencil_attachment_input_index,
+            )
+            .field(
+                "default_clear_color_inputs",
+                &self.default_clear_color_inputs,
+            )
+            .field(
+                "camera_bind_group_descriptor",
+                &self.camera_bind_group_descriptor,
+            )
+            .finish()
+    }
+}
+
 impl<Q: HecsQuery> PassNode<Q> {
     pub fn new(descriptor: PassDescriptor) -> Self {
         let mut inputs = Vec::new();
@@ -295,7 +326,7 @@ where
 }
 
 /// Tracks the current pipeline state to ensure draw calls are valid.
-#[derive(Default)]
+#[derive(Debug, Default)]
 struct DrawState {
     pipeline: Option<Handle<PipelineDescriptor>>,
     bind_groups: Vec<Option<BindGroupId>>,

crates/bevy_render/src/render_graph/nodes/shared_buffers_node.rs

@@ -4,7 +4,7 @@ use crate::{
 };
 use bevy_ecs::{Resources, World};
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct SharedBuffersNode;
 
 impl Node for SharedBuffersNode {

crates/bevy_render/src/render_graph/schedule.rs

@@ -107,7 +107,7 @@ pub trait RenderGraphStager {
 
 // TODO: remove this
 /// This scheduler ignores dependencies and puts everything in one stage. It shouldn't be used for anything :)
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct LinearStager;
 
 impl RenderGraphStager for LinearStager {
@@ -124,7 +124,7 @@ impl RenderGraphStager for LinearStager {
     }
 }
 
-#[derive(Copy, Clone)]
+#[derive(Debug, Copy, Clone)]
 /// Determines the grouping strategy used when constructing graph stages
 pub enum JobGrouping {
     /// Default to adding the current node to a new job in its assigned stage. This results
@@ -135,6 +135,7 @@ pub enum JobGrouping {
     Tight,
 }
 
+#[derive(Debug)]
 /// Produces Render Graph stages and jobs in a way that ensures node dependencies are respected.
 pub struct DependentNodeStager {
     job_grouping: JobGrouping,

crates/bevy_render/src/renderer/headless_render_resource_context.rs

@@ -11,7 +11,7 @@ use bevy_window::Window;
 use parking_lot::RwLock;
 use std::{ops::Range, sync::Arc};
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct HeadlessRenderResourceContext {
     buffer_info: Arc<RwLock<HashMap<BufferId, BufferInfo>>>,
     texture_descriptors: Arc<RwLock<HashMap<TextureId, TextureDescriptor>>>,

crates/bevy_render/src/renderer/render_resource/bind_group.rs

@@ -28,7 +28,7 @@ impl BindGroup {
     }
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct BindGroupBuilder {
     pub indexed_bindings: Vec<IndexedBindGroupEntry>,
     pub dynamic_uniform_indices: Vec<u32>,

crates/bevy_render/src/renderer/render_resource/render_resource_bindings.rs

@@ -253,7 +253,7 @@ impl RenderResourceBindings {
     }
 }
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct AssetRenderResourceBindings {
     pub bindings: HashMap<HandleUntyped, RenderResourceBindings>,
 }

crates/bevy_render/src/texture/texture.rs

@@ -11,7 +11,7 @@ use bevy_utils::HashSet;
 pub const TEXTURE_ASSET_INDEX: usize = 0;
 pub const SAMPLER_ASSET_INDEX: usize = 1;
 
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct Texture {
     pub data: Vec<u8>,
     pub size: Vec2,

crates/bevy_scene/src/loaded_scenes.rs

@@ -8,6 +8,7 @@ use parking_lot::RwLock;
 use serde::de::DeserializeSeed;
 use std::{path::Path, sync::Arc};
 
+#[derive(Debug)]
 pub struct SceneLoader {
     property_type_registry: Arc<RwLock<PropertyTypeRegistry>>,
 }

crates/bevy_scene/src/scene.rs

@@ -5,11 +5,12 @@ use bevy_property::{DynamicProperties, PropertyTypeRegistry};
 use bevy_type_registry::ComponentRegistry;
 use serde::Serialize;
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct Scene {
     pub entities: Vec<Entity>,
 }
 
+#[derive(Debug)]
 pub struct Entity {
     pub entity: u32,
     pub components: Vec<DynamicProperties>,

crates/bevy_scene/src/scene_spawner.rs

@@ -7,6 +7,7 @@ use bevy_utils::HashMap;
 use thiserror::Error;
 use uuid::Uuid;
 
+#[derive(Debug)]
 struct InstanceInfo {
     entity_map: HashMap<u32, bevy_ecs::Entity>,
 }

crates/bevy_scene/src/serde.rs

@@ -159,6 +159,7 @@ pub const ENTITY_STRUCT: &str = "Entity";
 pub const ENTITY_FIELD_ENTITY: &str = "entity";
 pub const ENTITY_FIELD_COMPONENTS: &str = "components";
 
+#[derive(Debug)]
 struct SceneEntityVisiter<'a> {
     pub registry: &'a PropertyTypeRegistry,
 }

crates/bevy_sprite/src/color_material.rs

@@ -1,7 +1,7 @@
 use bevy_asset::{self, Handle};
 use bevy_render::{color::Color, renderer::RenderResources, shader::ShaderDefs, texture::Texture};
 
-#[derive(RenderResources, ShaderDefs)]
+#[derive(Debug, RenderResources, ShaderDefs)]
 pub struct ColorMaterial {
     pub color: Color,
     #[shader_def]

crates/bevy_sprite/src/sprite.rs

@@ -4,7 +4,7 @@ use bevy_ecs::{Query, Res};
 use bevy_math::Vec2;
 use bevy_render::{renderer::RenderResources, texture::Texture};
 
-#[derive(Default, RenderResources)]
+#[derive(Debug, Default, RenderResources)]
 pub struct Sprite {
     pub size: Vec2,
     #[render_resources(ignore)]

crates/bevy_sprite/src/texture_atlas.rs

@@ -10,7 +10,7 @@ use bevy_render::{
 use bevy_utils::HashMap;
 
 /// An atlas containing multiple textures (like a spritesheet or a tilemap)
-#[derive(RenderResources)]
+#[derive(Debug, RenderResources)]
 pub struct TextureAtlas {
     /// The handle to the texture in which the sprites are stored
     pub texture: Handle<Texture>,
@@ -25,7 +25,7 @@ pub struct TextureAtlas {
 
 // NOTE: cannot do `unsafe impl Byteable` here because Vec3 takes up the space of a Vec4. If/when glam changes this we can swap out
 // Bytes for Byteable as a micro-optimization. https://github.com/bitshifter/glam-rs/issues/36
-#[derive(Bytes, RenderResources, RenderResource)]
+#[derive(Bytes, Debug, RenderResources, RenderResource)]
 #[render_resources(from_self)]
 pub struct TextureAtlasSprite {
     pub color: Color,

crates/bevy_sprite/src/texture_atlas_builder.rs

@@ -9,6 +9,7 @@ use rectangle_pack::{
 };
 use thiserror::Error;
 
+#[derive(Debug)]
 pub struct TextureAtlasBuilder {
     pub textures: Vec<Handle<Texture>>,
     pub rects_to_place: GroupedRectsToPlace<Handle<Texture>>,

crates/bevy_tasks/src/iter/adapters.rs

@@ -1,5 +1,6 @@
 use crate::iter::ParallelIterator;
 
+#[derive(Debug)]
 pub struct Chain<T, U> {
     pub(crate) left: T,
     pub(crate) right: U,
@@ -25,6 +26,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Map<P, F> {
     pub(crate) iter: P,
     pub(crate) f: F,
@@ -43,6 +45,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Filter<P, F> {
     pub(crate) iter: P,
     pub(crate) predicate: F,
@@ -63,6 +66,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct FilterMap<P, F> {
     pub(crate) iter: P,
     pub(crate) f: F,
@@ -81,6 +85,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct FlatMap<P, F> {
     pub(crate) iter: P,
     pub(crate) f: F,
@@ -103,6 +108,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Flatten<P> {
     pub(crate) iter: P,
 }
@@ -123,6 +129,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Fuse<P> {
     pub(crate) iter: Option<P>,
 }
@@ -148,6 +155,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Inspect<P, F> {
     pub(crate) iter: P,
     pub(crate) f: F,
@@ -166,6 +174,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Copied<P> {
     pub(crate) iter: P,
 }
@@ -183,6 +192,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Cloned<P> {
     pub(crate) iter: P,
 }
@@ -200,6 +210,7 @@ where
     }
 }
 
+#[derive(Debug)]
 pub struct Cycle<P> {
     pub(crate) iter: P,
     pub(crate) curr: Option<P>,

crates/bevy_tasks/src/single_threaded_task_pool.rs

@@ -104,12 +104,14 @@ impl TaskPool {
     }
 }
 
+#[derive(Debug)]
 pub struct FakeTask;
 
 impl FakeTask {
     pub fn detach(self) {}
 }
 
+#[derive(Debug)]
 pub struct Scope<'scope, T> {
     executor: &'scope async_executor::LocalExecutor<'scope>,
     // Vector to gather results of all futures spawned during scope run

crates/bevy_tasks/src/task.rs

@@ -13,6 +13,7 @@ use std::{
 ///
 /// Tasks that panic get immediately canceled. Awaiting a canceled task also causes a panic.
 /// Wraps async_executor::Task
+#[derive(Debug)]
 pub struct Task<T>(async_executor::Task<T>);
 
 impl<T> Task<T> {

crates/bevy_tasks/src/task_pool.rs

@@ -59,6 +59,7 @@ impl TaskPoolBuilder {
     }
 }
 
+#[derive(Debug)]
 struct TaskPoolInner {
     threads: Vec<JoinHandle<()>>,
     shutdown_tx: async_channel::Sender<()>,
@@ -78,7 +79,7 @@ impl Drop for TaskPoolInner {
 
 /// A thread pool for executing tasks. Tasks are futures that are being automatically driven by
 /// the pool on threads owned by the pool.
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct TaskPool {
     /// The executor for the pool
     ///
@@ -213,6 +214,7 @@ impl Default for TaskPool {
     }
 }
 
+#[derive(Debug)]
 pub struct Scope<'scope, T> {
     executor: &'scope async_executor::Executor<'scope>,
     spawned: Vec<async_executor::Task<T>>,

crates/bevy_tasks/src/usages.rs

@@ -15,7 +15,7 @@ use std::ops::Deref;
 
 /// A newtype for a task pool for CPU-intensive work that must be completed to deliver the next
 /// frame
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct ComputeTaskPool(pub TaskPool);
 
 impl Deref for ComputeTaskPool {
@@ -27,7 +27,7 @@ impl Deref for ComputeTaskPool {
 }
 
 /// A newtype for a task pool for CPU-intensive work that may span across multiple frames
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct AsyncComputeTaskPool(pub TaskPool);
 
 impl Deref for AsyncComputeTaskPool {
@@ -40,7 +40,7 @@ impl Deref for AsyncComputeTaskPool {
 
 /// A newtype for a task pool for IO-intensive work (i.e. tasks that spend very little time in a
 /// "woken" state)
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct IoTaskPool(pub TaskPool);
 
 impl Deref for IoTaskPool {

crates/bevy_text/src/draw.rs

@@ -15,7 +15,7 @@ use bevy_render::{
 };
 use bevy_sprite::{TextureAtlas, TextureAtlasSprite};
 
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct TextStyle {
     pub font_size: f32,
     pub color: Color,

crates/bevy_text/src/font.rs

@@ -5,6 +5,7 @@ use bevy_render::{
     texture::{Texture, TextureFormat},
 };
 
+#[derive(Debug)]
 pub struct Font {
     pub font: FontVec,
 }

crates/bevy_transform/src/hierarchy/child_builder.rs

@@ -2,6 +2,7 @@ use crate::prelude::{Children, Parent, PreviousParent};
 use bevy_ecs::{Commands, CommandsInternal, Component, DynamicBundle, Entity, WorldWriter};
 use smallvec::SmallVec;
 
+#[derive(Debug)]
 pub struct InsertChildren {
     parent: Entity,
     children: SmallVec<[Entity; 8]>,
@@ -35,11 +36,13 @@ impl WorldWriter for InsertChildren {
     }
 }
 
+#[derive(Debug)]
 pub struct PushChildren {
     parent: Entity,
     children: SmallVec<[Entity; 8]>,
 }
 
+#[derive(Debug)]
 pub struct ChildBuilder<'a> {
     commands: &'a mut CommandsInternal,
     push_children: PushChildren,

crates/bevy_transform/src/hierarchy/hierarchy.rs

@@ -39,6 +39,7 @@ where
     previous_result
 }
 
+#[derive(Debug)]
 pub struct DespawnRecursive {
     entity: Entity,
 }

crates/bevy_transform/src/hierarchy/world_child_builder.rs

@@ -1,6 +1,7 @@
 use crate::prelude::{Children, Parent, PreviousParent};
 use bevy_ecs::{Component, DynamicBundle, Entity, WorldBuilder};
 
+#[derive(Debug)]
 pub struct WorldChildBuilder<'a, 'b> {
     world_builder: &'b mut WorldBuilder<'a>,
     parent_entities: Vec<Entity>,

crates/bevy_ui/src/entity.rs

@@ -16,7 +16,7 @@ use bevy_render::{
 use bevy_sprite::{ColorMaterial, QUAD_HANDLE};
 use bevy_transform::prelude::{GlobalTransform, Transform};
 
-#[derive(Bundle, Clone)]
+#[derive(Bundle, Clone, Debug)]
 pub struct NodeComponents {
     pub node: Node,
     pub style: Style,
@@ -60,7 +60,7 @@ impl Default for NodeComponents {
     }
 }
 
-#[derive(Bundle, Clone)]
+#[derive(Bundle, Clone, Debug)]
 pub struct ImageComponents {
     pub node: Node,
     pub style: Style,
@@ -108,7 +108,7 @@ impl Default for ImageComponents {
     }
 }
 
-#[derive(Bundle, Clone)]
+#[derive(Bundle, Clone, Debug)]
 pub struct TextComponents {
     pub node: Node,
     pub style: Style,
@@ -138,7 +138,7 @@ impl Default for TextComponents {
     }
 }
 
-#[derive(Bundle, Clone)]
+#[derive(Bundle, Clone, Debug)]
 pub struct ButtonComponents {
     pub node: Node,
     pub button: Button,
@@ -188,7 +188,7 @@ impl Default for ButtonComponents {
     }
 }
 
-#[derive(Bundle)]
+#[derive(Bundle, Debug)]
 pub struct UiCameraComponents {
     pub camera: Camera,
     pub orthographic_projection: OrthographicProjection,

crates/bevy_ui/src/flex/mod.rs

@@ -6,6 +6,7 @@ use bevy_math::Vec2;
 use bevy_transform::prelude::{Children, Parent, Transform};
 use bevy_utils::HashMap;
 use bevy_window::{Window, WindowId, Windows};
+use std::fmt;
 use stretch::{number::Number, Stretch};
 
 pub struct FlexSurface {
@@ -14,6 +15,15 @@ pub struct FlexSurface {
     stretch: Stretch,
 }
 
+impl fmt::Debug for FlexSurface {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("FlexSurface")
+            .field("entity_to_stretch", &self.entity_to_stretch)
+            .field("window_nodes", &self.window_nodes)
+            .finish()
+    }
+}
+
 impl Default for FlexSurface {
     fn default() -> Self {
         Self {

crates/bevy_ui/src/node.rs

@@ -44,7 +44,7 @@ impl AddAssign<f32> for Val {
     }
 }
 
-#[derive(Default, Copy, Clone)]
+#[derive(Default, Copy, Clone, Debug)]
 pub struct CalculatedSize {
     pub size: Size,
 }

crates/bevy_ui/src/widget/button.rs

@@ -1,2 +1,2 @@
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub struct Button;

crates/bevy_ui/src/widget/image.rs

@@ -5,7 +5,7 @@ use bevy_math::Size;
 use bevy_render::texture::Texture;
 use bevy_sprite::ColorMaterial;
 
-#[derive(Clone)]
+#[derive(Debug, Clone)]
 pub enum Image {
     KeepAspect,
 }

crates/bevy_ui/src/widget/text.rs

@@ -12,12 +12,12 @@ use bevy_sprite::TextureAtlas;
 use bevy_text::{DrawableText, Font, FontAtlasSet, TextStyle};
 use bevy_transform::prelude::GlobalTransform;
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct QueuedText {
     entities: Vec<Entity>,
 }
 
-#[derive(Default, Clone)]
+#[derive(Debug, Default, Clone)]
 pub struct Text {
     pub value: String,
     pub font: Handle<Font>,

crates/bevy_wgpu/src/renderer/wgpu_render_context.rs

@@ -15,7 +15,7 @@ use bevy_render::{
 
 use std::sync::Arc;
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct LazyCommandEncoder {
     command_encoder: Option<wgpu::CommandEncoder>,
 }
@@ -50,6 +50,7 @@ impl LazyCommandEncoder {
     }
 }
 
+#[derive(Debug)]
 pub struct WgpuRenderContext {
     pub device: Arc<wgpu::Device>,
     pub command_encoder: LazyCommandEncoder,

crates/bevy_wgpu/src/renderer/wgpu_render_graph_executor.rs

@@ -8,6 +8,7 @@ use bevy_utils::HashMap;
 use parking_lot::RwLock;
 use std::sync::Arc;
 
+#[derive(Debug)]
 pub struct WgpuRenderGraphExecutor {
     pub max_thread_count: usize,
 }

crates/bevy_wgpu/src/renderer/wgpu_render_resource_context.rs

@@ -20,7 +20,7 @@ use futures_lite::future;
 use std::{borrow::Cow, ops::Range, sync::Arc};
 use wgpu::util::DeviceExt;
 
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WgpuRenderResourceContext {
     pub device: Arc<wgpu::Device>,
     pub resources: WgpuResources,

crates/bevy_wgpu/src/wgpu_render_pass.rs

@@ -7,6 +7,7 @@ use bevy_render::{
 };
 use std::ops::Range;
 
+#[derive(Debug)]
 pub struct WgpuRenderPass<'a> {
     pub render_pass: wgpu::RenderPass<'a>,
     pub render_context: &'a WgpuRenderContext,

crates/bevy_wgpu/src/wgpu_renderer.rs

@@ -7,6 +7,7 @@ use bevy_render::{
 };
 use bevy_window::{WindowCreated, WindowResized, Windows};
 use std::{ops::Deref, sync::Arc};
+
 pub struct WgpuRenderer {
     pub instance: wgpu::Instance,
     pub device: Arc<wgpu::Device>,

crates/bevy_wgpu/src/wgpu_resources.rs

@@ -10,7 +10,7 @@ use bevy_window::WindowId;
 use parking_lot::{RwLock, RwLockReadGuard};
 use std::sync::Arc;
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct WgpuBindGroupInfo {
     pub bind_groups: HashMap<BindGroupId, wgpu::BindGroup>,
 }
@@ -37,6 +37,7 @@ pub struct WgpuBindGroupInfo {
 ///
 /// Single threaded implementations don't need to worry about these lifetimes constraints at all. RenderPasses can use a RenderContext's
 /// WgpuResources directly. RenderContext already has a lifetime greater than the RenderPass.
+#[derive(Debug)]
 pub struct WgpuResourcesReadLock<'a> {
     pub buffers: RwLockReadGuard<'a, HashMap<BufferId, Arc<wgpu::Buffer>>>,
     pub textures: RwLockReadGuard<'a, HashMap<TextureId, wgpu::TextureView>>,
@@ -59,6 +60,7 @@ impl<'a> WgpuResourcesReadLock<'a> {
 }
 
 /// Stores read only references to WgpuResource collections. See WgpuResourcesReadLock docs for context on why this exists
+#[derive(Debug)]
 pub struct WgpuResourceRefs<'a> {
     pub buffers: &'a HashMap<BufferId, Arc<wgpu::Buffer>>,
     pub textures: &'a HashMap<TextureId, wgpu::TextureView>,
@@ -67,7 +69,7 @@ pub struct WgpuResourceRefs<'a> {
     pub bind_groups: &'a HashMap<BindGroupDescriptorId, WgpuBindGroupInfo>,
 }
 
-#[derive(Default, Clone)]
+#[derive(Default, Clone, Debug)]
 pub struct WgpuResources {
     pub buffer_infos: Arc<RwLock<HashMap<BufferId, BufferInfo>>>,
     pub texture_descriptors: Arc<RwLock<HashMap<TextureId, TextureDescriptor>>>,

crates/bevy_window/src/windows.rs

@@ -1,7 +1,7 @@
 use super::{Window, WindowId};
 use bevy_utils::HashMap;
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct Windows {
     windows: HashMap<WindowId, Window>,
 }

crates/bevy_winit/src/winit_config.rs

@@ -1,5 +1,5 @@
 /// A resource for configuring usage of the `rust_winit` library.
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct WinitConfig {
     /// Configures the winit library to return control to the main thread after
     /// the [run](bevy_app::App::run) loop is exited. Winit strongly recommends

crates/bevy_winit/src/winit_windows.rs

@@ -1,7 +1,7 @@
 use bevy_utils::HashMap;
 use bevy_window::{Window, WindowId, WindowMode};
 
-#[derive(Default)]
+#[derive(Debug, Default)]
 pub struct WinitWindows {
     pub windows: HashMap<winit::window::WindowId, winit::window::Window>,
     pub window_id_to_winit: HashMap<WindowId, winit::window::WindowId>,