Properly support patterns in inline_props (#760)

* Improve error messages for unsupported patterns * Support ident with subpatterns as props * Improve error messages
sycamore-rs · Nov 17, 2024 · 3b84a8b · 3b84a8b
1 parent 1e492e2
commit 3b84a8b
Show file tree

Hide file tree

Showing 4 changed files with 102 additions and 26 deletions.
diff --git a/packages/sycamore-macro/src/component.rs b/packages/sycamore-macro/src/component.rs
@@ -280,23 +280,31 @@ fn inline_props_impl(item: &mut ItemFn, attrs: Punctuated<Meta, Token![,]>) -> R
     let props = inputs.clone().into_iter().collect::<Vec<_>>();
     let generics: &mut Generics = &mut item.sig.generics;
     let mut fields = Vec::new();
-    inputs.into_iter().for_each(|arg| match arg {
-        FnArg::Receiver(_) => {
-            unreachable!("receiver cannot be a prop")
-        }
-        FnArg::Typed(pat_type) => match *pat_type.pat {
-            Pat::Ident(ident_pat) => super::inline_props::push_field(
-                &mut fields,
-                generics,
-                pat_type.attrs,
-                ident_pat.clone().ident,
-                *pat_type.ty,
-            ),
-            _ => {
-                unreachable!("unexpected pattern!")
+    for arg in inputs {
+        match arg {
+            FnArg::Receiver(receiver) => {
+                return Err(syn::Error::new(
+                    receiver.span(),
+                    "`self` cannot be a property",
+                ))
             }
-        },
-    });
+            FnArg::Typed(pat_type) => match *pat_type.pat {
+                Pat::Ident(ident_pat) => super::inline_props::push_field(
+                    &mut fields,
+                    generics,
+                    pat_type.attrs,
+                    ident_pat.clone().ident,
+                    *pat_type.ty,
+                ),
+                _ => {
+                    return Err(syn::Error::new(
+                        pat_type.pat.span(),
+                        "pattern must contain an identifier, properties cannot be unnamed",
+                    ))
+                }
+            },
+        }
+    }
 
     let generics_phantoms = generics.params.iter().enumerate().filter_map(|(i, param)| {
         let phantom_ident = format_ident!("__phantom{i}");
@@ -342,8 +350,18 @@ fn inline_props_impl(item: &mut ItemFn, attrs: Punctuated<Meta, Token![,]>) -> R
 
     // Get the ident (technically, patterns) of each prop.
     let props_pats = props.iter().map(|arg| match arg {
-        FnArg::Receiver(_) => unreachable!("receiver cannot be a prop"),
-        FnArg::Typed(arg) => arg.pat.clone(),
+        FnArg::Receiver(_) => unreachable!(),
+        FnArg::Typed(arg) => match &*arg.pat {
+            Pat::Ident(pat) => {
+                if pat.subpat.is_some() {
+                    let ident = &pat.ident;
+                    quote! { #ident: #pat }
+                } else {
+                    quote! { #pat }
+                }
+            }
+            _ => unreachable!(),
+        },
     });
     // Rewrite function signature.
     let props_struct_generics = generics.split_for_impl().1;

diff --git a/packages/sycamore-macro/tests/component/inline-props-fail.rs b/packages/sycamore-macro/tests/component/inline-props-fail.rs
@@ -5,4 +5,20 @@ fn NotInlineProps() -> View {
     view! {}
 }
 
+#[component(inline_props)]
+fn ReceiverProp(self) -> View {
+    view! {}
+}
+
+struct Foo {
+    bar: i32,
+}
+
+#[component(inline_props)]
+fn PatternWithoutIdent(Foo { bar }: Foo) -> View {
+    view! {
+        (bar)
+    }
+}
+
 fn main() {}
diff --git a/packages/sycamore-macro/tests/component/inline-props-fail.stderr b/packages/sycamore-macro/tests/component/inline-props-fail.stderr
@@ -3,3 +3,23 @@ error: expected `inline_props`
   |
 3 | #[component(not_inline_props)]
   |             ^^^^^^^^^^^^^^^^
+
+error: `self` cannot be a property
+ --> tests/component/inline-props-fail.rs:9:17
+  |
+9 | fn ReceiverProp(self) -> View {
+  |                 ^^^^
+
+error: pattern must contain an identifier, properties cannot be unnamed
+  --> tests/component/inline-props-fail.rs:18:24
+   |
+18 | fn PatternWithoutIdent(Foo { bar }: Foo) -> View {
+   |                        ^^^
+
+error: `self` parameter is only allowed in associated functions
+ --> tests/component/inline-props-fail.rs:9:17
+  |
+9 | fn ReceiverProp(self) -> View {
+  |                 ^^^^ not semantically valid as function parameter
+  |
+  = note: associated functions are those in `impl` or `trait` definitions
diff --git a/packages/sycamore-macro/tests/component/inline-props-pass.rs b/packages/sycamore-macro/tests/component/inline-props-pass.rs
@@ -1,4 +1,6 @@
-use sycamore::prelude::{component, view, Signal, View, Props};
+#![allow(unused_parens)]
+
+use sycamore::prelude::{component, view, Props, Signal, View};
 
 #[component(inline_props)]
 fn NoProps() -> View {
@@ -47,7 +49,10 @@ fn PropsWithImplGenerics(foo: impl std::fmt::Display + 'static) -> View {
 }
 
 #[component(inline_props)]
-fn PropsWithMixedImplGenerics<T: std::fmt::Display + 'static>(foo: T, bar: impl std::fmt::Display + 'static) -> View {
+fn PropsWithMixedImplGenerics<T: std::fmt::Display + 'static>(
+    foo: T,
+    bar: impl std::fmt::Display + 'static,
+) -> View {
     view! {
         (foo.to_string())
         (bar.to_string())
@@ -57,7 +62,10 @@ fn PropsWithMixedImplGenerics<T: std::fmt::Display + 'static>(foo: T, bar: impl
 #[component(inline_props)]
 fn PropsWithVariousImplGenerics(
     t1: [impl std::fmt::Display + 'static; 10],
-    t2: (impl std::fmt::Display + 'static, impl std::fmt::Display + 'static),
+    t2: (
+        impl std::fmt::Display + 'static,
+        impl std::fmt::Display + 'static,
+    ),
     t3: (impl std::fmt::Display + 'static),
     t4: impl std::fmt::Display + 'static,
     t5: *const (impl std::fmt::Display + 'static),
@@ -77,18 +85,17 @@ fn PropsWithVariousImplGenerics(
 
 #[component(inline_props, derive(Clone), derive(Debug))]
 fn AdditionalStructAttributes(dummy: String) -> View {
-    let props = AdditionalStructAttributes_Props::builder().dummy(dummy).build();
+    let props = AdditionalStructAttributes_Props::builder()
+        .dummy(dummy)
+        .build();
 
     view! {
         (format!("{:?}", props.clone()))
     }
 }
 
 #[component(inline_props)]
-fn PropsWithAttributes(
-    #[prop(default)]
-    dummy: String,
-) -> View {
+fn PropsWithAttributes(#[prop(default)] dummy: String) -> View {
     fn call_component() -> View {
         view! {
             PropsWithAttributes {}
@@ -99,4 +106,19 @@ fn PropsWithAttributes(
     }
 }
 
+#[derive(Debug)]
+struct Foo {
+    bar: u32,
+}
+
+#[component(inline_props)]
+fn PropsWithPatterns(mut a: u32, b @ Foo { bar }: Foo) -> View {
+    let _ = &mut a;
+    view! {
+        (a)
+        (format!("{b:?}"))
+        (bar)
+    }
+}
+
 fn main() {}