speed up detaching

Only remove nodes from the DOM when their parent remains
If the parent is also removed, no need to detach the nodes.

packages/yew/src/dom_bundle/app_handle.rs

@@ -37,7 +37,7 @@ where
 
     /// Schedule the app for destruction
     pub fn destroy(self) {
-        self.scope.destroy()
+        self.scope.destroy(false)
     }
 }
 

packages/yew/src/dom_bundle/bcomp.rs

@@ -40,8 +40,8 @@ impl fmt::Debug for BComp {
 }
 
 impl DomBundle for BComp {
-    fn detach(self, _parent: &Element) {
-        self.scope.destroy_boxed();
+    fn detach(self, _parent: &Element, parent_remains: bool) {
+        self.scope.destroy_boxed(parent_remains);
     }
 
     fn shift(&self, next_parent: &Element, next_sibling: NodeRef) {
@@ -264,9 +264,9 @@ impl ComponentRenderState {
         }
     }
     /// Detach the rendered content from the DOM
-    pub(crate) fn detach(self) {
+    pub(crate) fn detach(self, parent_remains: bool) {
         if let Some(ref m) = self.parent {
-            self.root_node.detach(m);
+            self.root_node.detach(m, parent_remains);
         }
     }
 
@@ -282,8 +282,8 @@ pub trait Scoped {
     /// Shift the node associated with this scope to a new place
     fn shift_node(&self, parent: Element, next_sibling: NodeRef);
     /// Process an event to destroy a component
-    fn destroy(self);
-    fn destroy_boxed(self: Box<Self>);
+    fn destroy(self, parent_remains: bool);
+    fn destroy_boxed(self: Box<Self>, parent_remains: bool);
 }
 
 #[cfg(test)]
@@ -565,7 +565,7 @@ mod tests {
         let (_, elem) = elem.attach(&scope, &parent, NodeRef::default());
         let parent_node = parent.deref();
         assert_eq!(node_ref.get(), parent_node.first_child());
-        elem.detach(&parent);
+        elem.detach(&parent, true);
         assert!(node_ref.get().is_none());
     }
 }

packages/yew/src/dom_bundle/blist.rs

@@ -151,7 +151,7 @@ impl BList {
         if lefts.len() < rights.len() {
             for r in rights.drain(lefts.len()..) {
                 test_log!("removing: {:?}", r);
-                r.detach(parent);
+                r.detach(parent, true);
             }
         }
 
@@ -336,7 +336,7 @@ impl BList {
         // Step 2.3. Remove any extra rights
         for KeyedEntry(_, r) in spare_bundles.drain() {
             test_log!("removing: {:?}", r);
-            r.detach(parent);
+            r.detach(parent, true);
         }
 
         // Step 3. Diff matching children at the start
@@ -354,9 +354,9 @@ impl BList {
 }
 
 impl DomBundle for BList {
-    fn detach(self, parent: &Element) {
+    fn detach(self, parent: &Element, parent_remains: bool) {
         for child in self.rev_children.into_iter() {
-            child.detach(parent);
+            child.detach(parent, parent_remains);
         }
     }
 

packages/yew/src/dom_bundle/bnode.rs

@@ -43,19 +43,21 @@ impl BNode {
 
 impl DomBundle for BNode {
     /// Remove VNode from parent.
-    fn detach(self, parent: &Element) {
+    fn detach(self, parent: &Element, parent_remains: bool) {
         match self {
-            Self::BTag(vtag) => vtag.detach(parent),
-            Self::BText(btext) => btext.detach(parent),
-            Self::BComp(bsusp) => bsusp.detach(parent),
-            Self::BList(blist) => blist.detach(parent),
+            Self::BTag(vtag) => vtag.detach(parent, parent_remains),
+            Self::BText(btext) => btext.detach(parent, parent_remains),
+            Self::BComp(bsusp) => bsusp.detach(parent, parent_remains),
+            Self::BList(blist) => blist.detach(parent, parent_remains),
             Self::BRef(ref node) => {
+                // Always remove nodes passed in by the user to disconnect it from
+                // internally generated nodes
                 if parent.remove_child(node).is_err() {
                     console::warn!("Node not found to remove VRef");
                 }
             }
-            Self::BPortal(bportal) => bportal.detach(parent),
-            Self::BSuspense(bsusp) => bsusp.detach(parent),
+            Self::BPortal(bportal) => bportal.detach(parent, parent_remains),
+            Self::BSuspense(bsusp) => bsusp.detach(parent, parent_remains),
         }
     }
 

packages/yew/src/dom_bundle/bportal.rs

@@ -20,9 +20,9 @@ pub struct BPortal {
 }
 
 impl DomBundle for BPortal {
-    fn detach(self, _: &Element) {
+    fn detach(self, _: &Element, _parent_remains: bool) {
         test_log!("Detaching portal from host{:?}", self.host.outer_html());
-        self.node.detach(&self.host);
+        self.node.detach(&self.host, true);
         test_log!("Detached portal from host{:?}", self.host.outer_html());
     }
 

packages/yew/src/dom_bundle/bsuspense.rs

@@ -30,12 +30,12 @@ impl BSuspense {
 }
 
 impl DomBundle for BSuspense {
-    fn detach(self, parent: &Element) {
+    fn detach(self, parent: &Element, parent_remains: bool) {
         if let Some(fallback) = self.fallback_bundle {
-            fallback.detach(parent);
-            self.children_bundle.detach(&self.detached_parent);
+            fallback.detach(parent, parent_remains);
+            self.children_bundle.detach(&self.detached_parent, false);
         } else {
-            self.children_bundle.detach(parent);
+            self.children_bundle.detach(parent, parent_remains);
         }
     }
 
@@ -164,7 +164,11 @@ impl Reconcilable for VSuspense {
             }
             // Freshly unsuspended. Detach fallback from the DOM, then shift children into it.
             (false, Some(_)) => {
-                suspense.fallback_bundle.take().unwrap().detach(parent);
+                suspense
+                    .fallback_bundle
+                    .take()
+                    .unwrap()
+                    .detach(parent, true);
 
                 children_bundle.shift(parent, next_sibling.clone());
                 children.reconcile_node(parent_scope, parent, next_sibling, children_bundle)

packages/yew/src/dom_bundle/btag/mod.rs

@@ -69,16 +69,19 @@ pub struct BTag {
 }
 
 impl DomBundle for BTag {
-    fn detach(self, parent: &Element) {
+    fn detach(self, parent: &Element, parent_remains: bool) {
         self.listeners.unregister();
 
         let node = self.reference;
         // recursively remove its children
         if let BTagInner::Other { child_bundle, .. } = self.inner {
-            child_bundle.detach(&node);
+            child_bundle.detach(&node, false);
         }
-        if parent.remove_child(&node).is_err() {
-            console::warn!("Node not found to remove VTag");
+        if parent_remains {
+            let removed_child = parent.remove_child(&node);
+            if removed_child.is_err() {
+                console::warn!("Node not found to remove VTag");
+            }
         }
         // It could be that the ref was already reused when rendering another element.
         // Only unset the ref it still belongs to our node
@@ -761,7 +764,7 @@ mod tests {
         assert_vtag_ref(&elem);
         let (_, elem) = elem.attach(&scope, &parent, NodeRef::default());
         assert_eq!(node_ref.get(), parent.first_child());
-        elem.detach(&parent);
+        elem.detach(&parent, true);
         assert!(node_ref.get().is_none());
     }
 

packages/yew/src/dom_bundle/btext.rs

@@ -15,10 +15,13 @@ pub struct BText {
 }
 
 impl DomBundle for BText {
-    fn detach(self, parent: &Element) {
-        let node = &self.text_node;
-        if parent.remove_child(node).is_err() {
-            console::warn!("Node not found to remove VText");
+    fn detach(self, parent: &Element, parent_remains: bool) {
+        if parent_remains {
+            let node = &self.text_node;
+            let removed_child = parent.remove_child(node);
+            if removed_child.is_err() {
+                console::warn!("Node not found to remove VText");
+            }
         }
     }
 

packages/yew/src/dom_bundle/mod.rs

@@ -41,7 +41,7 @@ use web_sys::{Element, Node};
 
 trait DomBundle {
     /// Remove self from parent.
-    fn detach(self, parent: &Element);
+    fn detach(self, parent: &Element, parent_remains: bool);
 
     /// Move elements from one parent to another parent.
     /// This is for example used by `VSuspense` to preserve component state without detaching
@@ -116,7 +116,7 @@ trait Reconcilable {
     {
         let (self_ref, self_) = self.attach(parent_scope, parent, next_sibling);
         let ancestor = std::mem::replace(bundle, self_.into());
-        ancestor.detach(parent);
+        ancestor.detach(parent, true);
         self_ref
     }
 }

packages/yew/src/dom_bundle/tests/layout_tests.rs

@@ -77,7 +77,7 @@ pub fn diff_layouts(layouts: Vec<TestLayout<'_>>) {
         );
 
         // Detach
-        bundle.detach(&parent_element);
+        bundle.detach(&parent_element, true);
         assert_eq!(
             parent_element.inner_html(),
             "END",
@@ -127,7 +127,7 @@ pub fn diff_layouts(layouts: Vec<TestLayout<'_>>) {
 
     // Detach last layout
     if let Some(bundle) = bundle {
-        bundle.detach(&parent_element);
+        bundle.detach(&parent_element, true);
     }
     assert_eq!(
         parent_element.inner_html(),

packages/yew/src/html/component/lifecycle.rs

@@ -131,10 +131,11 @@ impl<COMP: BaseComponent> ComponentState<COMP> {
         }
     }
 
-    pub(crate) fn push_destroy(self: &Rc<Self>) {
+    pub(crate) fn push_destroy(self: &Rc<Self>, parent_remains: bool) {
         let mut cbs = self.callbacks.borrow_mut();
         cbs.destroy = Some(DestroyPayload {
             _phantom: PhantomData,
+            parent_remains,
         });
         drop(cbs);
         scheduler::push_component_destroy(self.clone());
@@ -257,12 +258,13 @@ impl<COMP: BaseComponent> InnerComponentState<COMP> {
 }
 
 struct DestroyPayload<COMP: BaseComponent> {
+    parent_remains: bool,
     _phantom: PhantomData<COMP>,
 }
 
 impl<COMP: BaseComponent> RunDestroy for ComponentState<COMP> {
     fn run_destroy(self: Rc<Self>) {
-        let _payload = {
+        let payload = {
             let mut cbs = self.callbacks.borrow_mut();
             match cbs.destroy.take() {
                 Some(p) => p,
@@ -274,7 +276,7 @@ impl<COMP: BaseComponent> RunDestroy for ComponentState<COMP> {
             super::log_event(self.vcomp_id, "destroy");
 
             state.component.destroy(&state.context);
-            state.render_state.detach();
+            state.render_state.detach(payload.parent_remains);
             state.node_ref.set(None);
         }
     }

packages/yew/src/html/component/scope.rs

@@ -127,14 +127,14 @@ impl<COMP: BaseComponent> Scoped for Scope<COMP> {
         }))
     }
 
-    fn destroy(self) {
-        self.state.push_destroy();
+    fn destroy(self, parent_remains: bool) {
+        self.state.push_destroy(parent_remains);
         // Not guaranteed to already have the scheduler started
         scheduler::start();
     }
 
-    fn destroy_boxed(self: Box<Self>) {
-        self.destroy()
+    fn destroy_boxed(self: Box<Self>, parent_remains: bool) {
+        self.destroy(parent_remains)
     }
 
     fn shift_node(&self, parent: Element, next_sibling: NodeRef) {
@@ -336,7 +336,7 @@ mod feat_ssr {
             let self_any_scope = self.to_any();
             html.render_to_string(w, &self_any_scope).await;
 
-            self.destroy();
+            self.destroy(true);
         }
     }
 }