From ef687816edd5c5cbcbc3b6959ea17f01e2938b78 Mon Sep 17 00:00:00 2001
From: Carter Anderson <mcanders1@gmail.com>
Date: Sun, 5 Feb 2023 16:08:44 -0800
Subject: [PATCH] Resolve comments

---
 crates/bevy_ecs/src/schedule_v3/config.rs | 24 +++++++++++------------
 crates/bevy_ecs/src/schedule_v3/set.rs    |  8 ++++++--
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/crates/bevy_ecs/src/schedule_v3/config.rs b/crates/bevy_ecs/src/schedule_v3/config.rs
index 316915382159e..bb171871f0462 100644
--- a/crates/bevy_ecs/src/schedule_v3/config.rs
+++ b/crates/bevy_ecs/src/schedule_v3/config.rs
@@ -88,7 +88,7 @@ pub trait IntoSystemSetConfig: sealed::IntoSystemSetConfig {
     /// Add to the provided `set`.
     #[track_caller]
     fn in_set(self, set: impl SystemSet) -> SystemSetConfig;
-    /// Add to the provided "base" `set`.
+    /// Add to the provided "base" `set`. For more information on base sets, see [`SystemSet::is_base`].
     #[track_caller]
     fn in_base_set(self, set: impl SystemSet) -> SystemSetConfig;
     /// Add this set to the schedules's default base set.
@@ -230,11 +230,11 @@ impl IntoSystemSetConfig for SystemSetConfig {
     fn in_base_set(mut self, set: impl SystemSet) -> Self {
         assert!(
             !set.is_system_type(),
-            "adding arbitrary systems to a system type set is not allowed"
+            "System type sets cannot be base sets."
         );
         assert!(
             set.is_base(),
-            "Normal sets cannot be added to system sets using 'in_base_set'. Use 'in_set' instead."
+            "Sets cannot be added to normal sets using 'in_base_set'. Use 'in_set' instead."
         );
         assert!(
             !self.set.is_base(),
@@ -296,7 +296,7 @@ pub trait IntoSystemConfig<Params>: sealed::IntoSystemConfig<Params> {
     /// Add to `set` membership.
     #[track_caller]
     fn in_set(self, set: impl SystemSet) -> SystemConfig;
-    /// Add to the "base" `set` membership.
+    /// Add to the provided "base" `set`. For more information on base sets, see [`SystemSet::is_base`].
     #[track_caller]
     fn in_base_set(self, set: impl SystemSet) -> SystemConfig;
     /// Don't add this system to the schedules's default set.
@@ -434,11 +434,11 @@ impl IntoSystemConfig<()> for SystemConfig {
     fn in_base_set(mut self, set: impl SystemSet) -> Self {
         assert!(
             !set.is_system_type(),
-            "adding arbitrary systems to a system type set is not allowed"
+            "System type sets cannot be base sets."
         );
         assert!(
             set.is_base(),
-            "Systems cannot be added to normal system sets using 'in_base_set'. Use 'in_set' instead."
+            "Systems cannot be added to normal sets using 'in_base_set'. Use 'in_set' instead."
         );
         self.graph_info.set_base_set(Box::new(set));
         self
@@ -533,7 +533,7 @@ where
         self.into_configs().in_set(set)
     }
 
-    /// Add these systems to the provided "base" `set`.
+    /// Add these systems to the provided "base" `set`. For more information on base sets, see [`SystemSet::is_base`].
     #[track_caller]
     fn in_base_set(self, set: impl SystemSet) -> SystemConfigs {
         self.into_configs().in_base_set(set)
@@ -600,11 +600,11 @@ impl IntoSystemConfigs<()> for SystemConfigs {
     fn in_base_set(mut self, set: impl SystemSet) -> Self {
         assert!(
             !set.is_system_type(),
-            "adding arbitrary systems to a system type set is not allowed"
+            "System type sets cannot be base sets."
         );
         assert!(
             set.is_base(),
-            "Systems cannot be added to normal system sets using 'in_base_set'. Use 'in_set' instead."
+            "Systems cannot be added to normal sets using 'in_base_set'. Use 'in_set' instead."
         );
         for config in &mut self.systems {
             config.graph_info.set_base_set(set.dyn_clone());
@@ -686,7 +686,7 @@ where
         self.into_configs().in_set(set)
     }
 
-    /// Add these system sets to the provided "base" `set`.
+    /// Add these system sets to the provided "base" `set`. For more information on base sets, see [`SystemSet::is_base`].
     #[track_caller]
     fn in_base_set(self, set: impl SystemSet) -> SystemSetConfigs {
         self.into_configs().in_base_set(set)
@@ -752,11 +752,11 @@ impl IntoSystemSetConfigs for SystemSetConfigs {
     fn in_base_set(mut self, set: impl SystemSet) -> Self {
         assert!(
             !set.is_system_type(),
-            "adding arbitrary systems to a system type set is not allowed"
+            "System type sets cannot be base sets."
         );
         assert!(
             set.is_base(),
-            "Sets cannot be added to normal system sets using 'in_base_set'. Use 'in_set' instead."
+            "Sets cannot be added to normal sets using 'in_base_set'. Use 'in_set' instead."
         );
         for config in &mut self.sets {
             assert!(
diff --git a/crates/bevy_ecs/src/schedule_v3/set.rs b/crates/bevy_ecs/src/schedule_v3/set.rs
index c4de92e63d03a..c5f62f9259d00 100644
--- a/crates/bevy_ecs/src/schedule_v3/set.rs
+++ b/crates/bevy_ecs/src/schedule_v3/set.rs
@@ -23,8 +23,12 @@ pub trait SystemSet: DynHash + Debug + Send + Sync + 'static {
         false
     }
 
-    /// Returns `true` if this set is a "base system set", which systems
-    /// can only belong to one of.
+    /// Returns `true` if this set is a "base system set". Systems
+    /// can only belong to one base set at a time. Systems and Sets
+    /// can only be added to base sets using specialized `in_base_set`
+    /// APIs. This enables "mutually exclusive" behaviors. It also
+    /// enables schedules to have a "default base set", which can be used
+    /// to apply default configuration to systems.
     fn is_base(&self) -> bool {
         false
     }