el_key - alpha version

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 [unreleased]
 - [BREAKING] Changed `perform_cmd` and `fetch` return type to `T` instead of `Result<T, T>`.
+- Added `el_key` method for adding keys to `El`s [WIP].
 
 ## v0.6.0
 - Implemented `UpdateEl` for `Filter` and `FilterMap`.

src/lib.rs

@@ -99,8 +99,8 @@ pub mod prelude {
         // https://github.com/rust-lang-nursery/reference/blob/master/src/macros-by-example.md
         shortcuts::*,
         virtual_dom::{
-            el_ref::el_ref, AsAtValue, At, AtValue, CSSValue, El, ElRef, Ev, EventHandler, Node,
-            St, Tag, UpdateEl, View,
+            el_key, el_ref::el_ref, AsAtValue, At, AtValue, CSSValue, El, ElRef, Ev, EventHandler,
+            Node, St, Tag, UpdateEl, View,
         },
     };
     pub use indexmap::IndexMap; // for attrs and style to work.

src/virtual_dom.rs

@@ -13,7 +13,7 @@ pub use attrs::Attrs;
 pub use el_ref::{el_ref, ElRef, SharedNodeWs};
 pub use event_handler_manager::{EventHandler, EventHandlerManager, Listener};
 pub use mailbox::Mailbox;
-pub use node::{El, IntoNodes, Node, Text};
+pub use node::{el_key, El, ElKey, IntoNodes, Node, Text};
 pub use style::Style;
 pub use update_el::UpdateEl;
 pub use values::{AsAtValue, AtValue, CSSValue};

src/virtual_dom/node.rs

@@ -6,7 +6,7 @@ pub mod el;
 pub mod into_nodes;
 pub mod text;
 
-pub use el::El;
+pub use el::{el_key, El, ElKey};
 pub use into_nodes::IntoNodes;
 pub use text::Text;
 

src/virtual_dom/node/el.rs

@@ -9,6 +9,26 @@ use crate::browser::{
 };
 use std::borrow::Cow;
 
+// ------ ElKey ------
+
+#[allow(clippy::module_name_repetitions)]
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ElKey(String);
+
+#[allow(clippy::module_name_repetitions)]
+/// Attach given `key` to the `El`.
+///
+/// ## Warning
+///
+/// WIP
+///  - it doesn't patch elements with the different keys, BUT it replace the old element with the new one.
+///  - `key` restriction (have to implements `ToString`) will be probably relaxed in the future.
+pub fn el_key(key: &impl ToString) -> ElKey {
+    ElKey(key.to_string())
+}
+
+// ------ El ------
+
 /// A component in our virtual DOM.
 ///
 /// _Note:_ `Listener`s in `El`'s `event_handler_manager` are not cloned, but recreated during VDOM patching.
@@ -29,6 +49,7 @@ pub struct El<Ms: 'static> {
     /// The actual DOM element/node.
     pub node_ws: Option<web_sys::Node>,
     pub refs: Vec<SharedNodeWs>,
+    pub key: Option<ElKey>,
 }
 
 // @TODO remove custom impl once https://github.com/rust-lang/rust/issues/26925 is fixed
@@ -43,6 +64,7 @@ impl<Ms> Clone for El<Ms> {
             namespace: self.namespace.clone(),
             node_ws: self.node_ws.clone(),
             refs: self.refs.clone(),
+            key: self.key.clone(),
         }
     }
 }
@@ -71,6 +93,7 @@ impl<Ms: 'static, OtherMs: 'static> MessageMapper<Ms, OtherMs> for El<Ms> {
             namespace: self.namespace,
             event_handler_manager: self.event_handler_manager.map_msg(f),
             refs: self.refs,
+            key: self.key,
         }
     }
 }
@@ -94,6 +117,7 @@ impl<Ms> El<Ms> {
             namespace: None,
             node_ws: None,
             refs: Vec::new(),
+            key: None,
         }
     }
 

src/virtual_dom/patch.rs

@@ -27,7 +27,8 @@ fn patch_el<'a, Ms, Mdl, ElC: View<Ms>, GMs>(
     // Namespaces can't be patched, since they involve create_element_ns instead of create_element.
     // Custom elements can't be patched, because we need to reinit them (Issue #325). (@TODO is there a better way?)
     // Something about this element itself is different: patch it.
-    if old.tag != new.tag || old.namespace != new.namespace || old.is_custom() {
+    if old.tag != new.tag || old.namespace != new.namespace || old.is_custom() || old.key != new.key
+    {
         let old_el_ws = old.node_ws.as_ref().expect("Missing websys el");
 
         // We don't use assign_nodes directly here, since we only have access to

src/virtual_dom/update_el.rs

@@ -1,4 +1,4 @@
-use super::{Attrs, El, ElRef, EventHandler, Node, Style, Tag, Text};
+use super::{Attrs, El, ElKey, ElRef, EventHandler, Node, Style, Tag, Text};
 
 /// `UpdateEl` is used to distinguish arguments in element-creation macros, and handle
 /// each type appropriately.
@@ -133,6 +133,12 @@ impl<Ms, E: Clone> UpdateEl<El<Ms>> for ElRef<E> {
     }
 }
 
+impl<Ms> UpdateEl<El<Ms>> for ElKey {
+    fn update(self, el: &mut El<Ms>) {
+        el.key = Some(self);
+    }
+}
+
 // ----- Iterators ------
 
 impl<Ms, I, U, F> UpdateEl<El<Ms>> for std::iter::Map<I, F>