Remove support for element listener magical closures (#782)

crates/macro/src/html_tree/html_tag/mod.rs

@@ -149,7 +149,10 @@ impl ToTokens for HtmlTag {
                 #vtag.node_ref = #node_ref;
             }
         });
-        let listeners = listeners.iter().map(|(name, callback)| {
+        let listeners = listeners.iter().map(|listener| {
+            let name = &listener.label.name;
+            let callback = &listener.value;
+
             quote_spanned! {name.span()=> {
                 ::yew::html::#name::Wrapper::new(
                     <::yew::virtual_dom::vtag::VTag<_> as ::yew::virtual_dom::Transformer<_, _, _>>::transform(

crates/macro/src/html_tree/html_tag/tag_attributes.rs

@@ -1,15 +1,14 @@
 use crate::html_tree::HtmlProp as TagAttribute;
 use crate::PeekValue;
 use lazy_static::lazy_static;
-use proc_macro2::TokenStream;
-use quote::{quote, quote_spanned, ToTokens};
-use std::collections::HashMap;
+use std::collections::HashSet;
+use std::iter::FromIterator;
 use syn::parse::{Parse, ParseStream, Result as ParseResult};
-use syn::{Expr, ExprClosure, ExprTuple, Ident, Pat};
+use syn::{Expr, ExprTuple};
 
 pub struct TagAttributes {
     pub attributes: Vec<TagAttribute>,
-    pub listeners: Vec<(Ident, TokenStream)>,
+    pub listeners: Vec<TagAttribute>,
     pub classes: Option<ClassesForm>,
     pub value: Option<Expr>,
     pub kind: Option<Expr>,
@@ -25,75 +24,67 @@ pub enum ClassesForm {
     Single(Expr),
 }
 
-pub struct TagListener {
-    name: Ident,
-    handler: Expr,
-    event_name: String,
-}
-
 lazy_static! {
-    static ref LISTENER_MAP: HashMap<&'static str, &'static str> = {
-        let mut m = HashMap::new();
-        m.insert("onclick", "ClickEvent");
-        m.insert("ondoubleclick", "DoubleClickEvent");
-        m.insert("onkeypress", "KeyPressEvent");
-        m.insert("onkeydown", "KeyDownEvent");
-        m.insert("onkeyup", "KeyUpEvent");
-        m.insert("onmousedown", "MouseDownEvent");
-        m.insert("onmousemove", "MouseMoveEvent");
-        m.insert("onmouseout", "MouseOutEvent");
-        m.insert("onmouseenter", "MouseEnterEvent");
-        m.insert("onmouseleave", "MouseLeaveEvent");
-        m.insert("onmousewheel", "MouseWheelEvent");
-        m.insert("onmouseover", "MouseOverEvent");
-        m.insert("onmouseup", "MouseUpEvent");
-        m.insert("ontouchcancel", "TouchCancel");
-        m.insert("ontouchend", "TouchEnd");
-        m.insert("ontouchenter", "TouchEnter");
-        m.insert("ontouchmove", "TouchMove");
-        m.insert("ontouchstart", "TouchStart");
-        m.insert("ongotpointercapture", "GotPointerCaptureEvent");
-        m.insert("onlostpointercapture", "LostPointerCaptureEvent");
-        m.insert("onpointercancel", "PointerCancelEvent");
-        m.insert("onpointerdown", "PointerDownEvent");
-        m.insert("onpointerenter", "PointerEnterEvent");
-        m.insert("onpointerleave", "PointerLeaveEvent");
-        m.insert("onpointermove", "PointerMoveEvent");
-        m.insert("onpointerout", "PointerOutEvent");
-        m.insert("onpointerover", "PointerOverEvent");
-        m.insert("onpointerup", "PointerUpEvent");
-        m.insert("onscroll", "ScrollEvent");
-        m.insert("onblur", "BlurEvent");
-        m.insert("onfocus", "FocusEvent");
-        m.insert("onsubmit", "SubmitEvent");
-        m.insert("oninput", "InputData");
-        m.insert("onchange", "ChangeData");
-        m.insert("ondrag", "DragEvent");
-        m.insert("ondragstart", "DragStartEvent");
-        m.insert("ondragend", "DragEndEvent");
-        m.insert("ondragenter", "DragEnterEvent");
-        m.insert("ondragleave", "DragLeaveEvent");
-        m.insert("ondragover", "DragOverEvent");
-        m.insert("ondragexit", "DragExitEvent");
-        m.insert("ondrop", "DragDropEvent");
-        m.insert("oncontextmenu", "ContextMenuEvent");
-        m
+    static ref LISTENER_SET: HashSet<&'static str> = {
+        HashSet::from_iter(
+            vec![
+                "onclick",
+                "ondoubleclick",
+                "onkeypress",
+                "onkeydown",
+                "onkeyup",
+                "onmousedown",
+                "onmousemove",
+                "onmouseout",
+                "onmouseenter",
+                "onmouseleave",
+                "onmousewheel",
+                "onmouseover",
+                "onmouseup",
+                "ontouchcancel",
+                "ontouchend",
+                "ontouchenter",
+                "ontouchmove",
+                "ontouchstart",
+                "ongotpointercapture",
+                "onlostpointercapture",
+                "onpointercancel",
+                "onpointerdown",
+                "onpointerenter",
+                "onpointerleave",
+                "onpointermove",
+                "onpointerout",
+                "onpointerover",
+                "onpointerup",
+                "onscroll",
+                "onblur",
+                "onfocus",
+                "onsubmit",
+                "oninput",
+                "onchange",
+                "ondrag",
+                "ondragstart",
+                "ondragend",
+                "ondragenter",
+                "ondragleave",
+                "ondragover",
+                "ondragexit",
+                "ondrop",
+                "oncontextmenu",
+            ]
+            .into_iter(),
+        )
     };
 }
 
 impl TagAttributes {
-    fn drain_listeners(attrs: &mut Vec<TagAttribute>) -> Vec<TagListener> {
+    fn drain_listeners(attrs: &mut Vec<TagAttribute>) -> Vec<TagAttribute> {
         let mut i = 0;
         let mut drained = Vec::new();
         while i < attrs.len() {
             let name_str = attrs[i].label.to_string();
-            if let Some(event_type) = LISTENER_MAP.get(&name_str.as_str()) {
-                let TagAttribute { label, value } = attrs.remove(i);
-                drained.push(TagListener {
-                    name: label.name,
-                    handler: value,
-                    event_name: event_type.to_owned().to_string(),
-                });
+            if LISTENER_SET.contains(&name_str.as_str()) {
+                drained.push(attrs.remove(i));
             } else {
                 i += 1;
             }
@@ -119,54 +110,6 @@ impl TagAttributes {
             expr => ClassesForm::Single(expr),
         }
     }
-
-    fn map_listener(listener: TagListener) -> ParseResult<(Ident, TokenStream)> {
-        let TagListener {
-            name,
-            event_name,
-            handler,
-        } = listener;
-
-        let callback: TokenStream = match handler {
-            Expr::Closure(closure) => {
-                let ExprClosure {
-                    inputs,
-                    body,
-                    or1_token,
-                    or2_token,
-                    ..
-                } = closure;
-
-                let or_span = quote! {#or1_token#or2_token};
-                if inputs.len() != 1 {
-                    return Err(syn::Error::new_spanned(
-                        or_span,
-                        "there must be one closure argument",
-                    ));
-                }
-
-                let var = match inputs.first().unwrap() {
-                    Pat::Ident(pat) => Ok(pat.into_token_stream()),
-                    Pat::Wild(pat) => Ok(pat.into_token_stream()),
-                    _ => Err(syn::Error::new_spanned(or_span, "invalid closure argument")),
-                }?;
-                let callback =
-                    Ident::new(&format!("__yew_{}_callback", name.to_string()), name.span());
-                let segment = syn::PathSegment {
-                    ident: Ident::new(&event_name, name.span()),
-                    arguments: syn::PathArguments::None,
-                };
-
-                quote_spanned! {name.span()=> {
-                    let #callback = move | #var: ::yew::events::#segment | #body;
-                    #callback
-                }}
-            }
-            callback => callback.into_token_stream(),
-        };
-
-        Ok((name, callback))
-    }
 }
 
 impl Parse for TagAttributes {
@@ -178,7 +121,7 @@ impl Parse for TagAttributes {
 
         let mut listeners = Vec::new();
         for listener in TagAttributes::drain_listeners(&mut attributes) {
-            listeners.push(TagAttributes::map_listener(listener)?);
+            listeners.push(listener);
         }
 
         // Multiple listener attributes are allowed, but no others

tests/macro/html-tag-fail.rs

@@ -30,9 +30,7 @@ fn compile_fail() {
     html! { <a href=() /> };
 
     html! { <input onclick=1 /> };
-    html! { <input onclick=|| () /> };
-    html! { <input onclick=|a, b| () /> };
-    html! { <input onclick=|a: String| () /> };
+    html! { <input onclick=Callback::from(|a: String| ()) /> };
 
     html! { <input string=NotToString /> };
 

tests/macro/html-tag-fail.stderr

@@ -102,28 +102,10 @@ error: only one `class` attribute allowed
 23 |     html! { <div class="first" class="second" /> };
    |                                ^^^^^
 
-error: there must be one closure argument
-  --> $DIR/html-tag-fail.rs:33:28
-   |
-33 |     html! { <input onclick=|| () /> };
-   |                            ^^
-
-error: there must be one closure argument
-  --> $DIR/html-tag-fail.rs:34:28
-   |
-34 |     html! { <input onclick=|a, b| () /> };
-   |                            ^^^^^^
-
-error: invalid closure argument
-  --> $DIR/html-tag-fail.rs:35:28
-   |
-35 |     html! { <input onclick=|a: String| () /> };
-   |                            ^^^^^^^^^^^
-
 error: only one `ref` attribute allowed
-  --> $DIR/html-tag-fail.rs:40:27
+  --> $DIR/html-tag-fail.rs:38:27
    |
-40 |     html! { <input ref=() ref=() /> };
+38 |     html! { <input ref=() ref=() /> };
    |                           ^^^
 
 error[E0308]: mismatched types
@@ -193,13 +175,22 @@ error[E0308]: mismatched types
    = note: expected type `yew::callback::Callback<stdweb::webapi::events::mouse::ClickEvent>`
               found type `{integer}`
 
+error[E0308]: mismatched types
+  --> $DIR/html-tag-fail.rs:33:20
+   |
+33 |     html! { <input onclick=Callback::from(|a: String| ()) /> };
+   |                    ^^^^^^^ expected struct `stdweb::webapi::events::mouse::ClickEvent`, found struct `std::string::String`
+   |
+   = note: expected type `yew::callback::Callback<stdweb::webapi::events::mouse::ClickEvent>`
+              found type `yew::callback::Callback<std::string::String>`
+
 error[E0599]: no method named `to_string` found for type `NotToString` in the current scope
-  --> $DIR/html-tag-fail.rs:37:27
+  --> $DIR/html-tag-fail.rs:35:27
    |
 3  | struct NotToString;
    | ------------------- method `to_string` not found for this
 ...
-37 |     html! { <input string=NotToString /> };
+35 |     html! { <input string=NotToString /> };
    |                           ^^^^^^^^^^^ method not found in `NotToString`
    |
    = note: the method `to_string` exists but the following trait bounds were not satisfied:
@@ -209,9 +200,9 @@ error[E0599]: no method named `to_string` found for type `NotToString` in the cu
            candidate #1: `std::string::ToString`
 
 error[E0308]: mismatched types
-  --> $DIR/html-tag-fail.rs:39:24
+  --> $DIR/html-tag-fail.rs:37:24
    |
-39 |     html! { <input ref=() /> };
+37 |     html! { <input ref=() /> };
    |                        ^^ expected struct `yew::html::NodeRef`, found ()
    |
    = note: expected type `yew::html::NodeRef`

tests/macro/html-tag-pass.rs

@@ -37,7 +37,6 @@ pass_helper! {
             </svg>
             <img class=("avatar", "hidden") src="http://pic.com" />
             <img class="avatar hidden", />
-            <button onclick=|e| panic!(e) />
             <button onclick=&onclick />
             <button onclick=onclick />
             <a href="http://google.com" />