Merge pull request #1569 from dtolnay/cfgvisit

Render doc cfg on Visit/VisitMut/Fold trait methods
dtolnay · Jan 1, 2024 · 4523437 · 4523437
2 parents 1728630 + 694a1bb
commit 4523437
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Showing 9 changed files with 1,053 additions and 17 deletions.
diff --git a/codegen/src/cfg.rs b/codegen/src/cfg.rs
@@ -2,11 +2,28 @@ use proc_macro2::TokenStream;
 use quote::quote;
 use syn_codegen::Features;
 
-pub fn features(features: &Features) -> TokenStream {
+pub fn features<'a>(
+    features: &Features,
+    overriding_cfg: impl Into<Option<&'a str>>,
+) -> TokenStream {
     let features = &features.any;
-    match features.len() {
-        0 => quote!(),
-        1 => quote!(#[cfg(feature = #(#features)*)]),
-        _ => quote!(#[cfg(any(#(feature = #features),*))]),
+    let cfg = match features.len() {
+        0 => None,
+        1 => Some(quote! { cfg(feature = #(#features)*) }),
+        _ => Some(quote! { cfg(any(#(feature = #features),*)) }),
+    };
+    match (cfg, overriding_cfg.into()) {
+        (Some(cfg), Some(overriding_cfg)) => quote! {
+            #[#cfg]
+            #[cfg_attr(doc_cfg, doc(cfg(feature = #overriding_cfg)))]
+        },
+        (Some(cfg), None) => quote! {
+            #[#cfg]
+            #[cfg_attr(doc_cfg, doc(#cfg))]
+        },
+        (None, Some(overriding_cfg)) => quote! {
+            #[cfg_attr(doc_cfg, doc(cfg(feature = #overriding_cfg)))]
+        },
+        (None, None) => TokenStream::new(),
     }
 }
diff --git a/codegen/src/clone.rs b/codegen/src/clone.rs
@@ -76,7 +76,7 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
     }
 
     let ident = Ident::new(&node.ident, Span::call_site());
-    let cfg_features = cfg::features(&node.features);
+    let cfg_features = cfg::features(&node.features, "clone-impls");
 
     let copy = node.ident == "AttrStyle"
         || node.ident == "BinOp"
@@ -86,10 +86,8 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
     if copy {
         return quote! {
             #cfg_features
-            #[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))]
             impl Copy for #ident {}
             #cfg_features
-            #[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))]
             impl Clone for #ident {
                 fn clone(&self) -> Self {
                     *self
@@ -102,7 +100,6 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
 
     quote! {
         #cfg_features
-        #[cfg_attr(doc_cfg, doc(cfg(feature = "clone-impls")))]
         impl Clone for #ident {
             fn clone(&self) -> Self {
                 #body

diff --git a/codegen/src/debug.rs b/codegen/src/debug.rs
@@ -147,7 +147,7 @@ fn expand_impl(defs: &Definitions, node: &Node, syntax_tree_variants: &Set<&str>
     }
 
     let ident = Ident::new(&node.ident, Span::call_site());
-    let cfg_features = cfg::features(&node.features);
+    let cfg_features = cfg::features(&node.features, "extra-traits");
     let body = expand_impl_body(defs, node, syntax_tree_variants);
     let formatter = match &node.data {
         Data::Enum(variants) if variants.is_empty() => quote!(_formatter),
@@ -156,7 +156,6 @@ fn expand_impl(defs: &Definitions, node: &Node, syntax_tree_variants: &Set<&str>
 
     quote! {
         #cfg_features
-        #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
         impl Debug for #ident {
             fn fmt(&self, #formatter: &mut fmt::Formatter) -> fmt::Result {
                 #body

diff --git a/codegen/src/eq.rs b/codegen/src/eq.rs
@@ -114,11 +114,10 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
     }
 
     let ident = Ident::new(&node.ident, Span::call_site());
-    let cfg_features = cfg::features(&node.features);
+    let cfg_features = cfg::features(&node.features, "extra-traits");
 
     let eq = quote! {
         #cfg_features
-        #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
         impl Eq for #ident {}
     };
 
@@ -138,7 +137,6 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
         #eq
 
         #cfg_features
-        #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
         impl PartialEq for #ident {
             fn eq(&self, #other: &Self) -> bool {
                 #body

diff --git a/codegen/src/gen.rs b/codegen/src/gen.rs
@@ -27,7 +27,7 @@ pub fn traverse(
     let mut traits = TokenStream::new();
     let mut impls = TokenStream::new();
     for s in types {
-        let features = cfg::features(&s.features);
+        let features = cfg::features(&s.features, None);
         traits.extend(features.clone());
         impls.extend(features);
         node(&mut traits, &mut impls, &s, defs);

diff --git a/codegen/src/hash.rs b/codegen/src/hash.rs
@@ -123,7 +123,7 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
     }
 
     let ident = Ident::new(&node.ident, Span::call_site());
-    let cfg_features = cfg::features(&node.features);
+    let cfg_features = cfg::features(&node.features, "extra-traits");
 
     let body = expand_impl_body(defs, node);
 
@@ -135,7 +135,6 @@ fn expand_impl(defs: &Definitions, node: &Node) -> TokenStream {
 
     quote! {
         #cfg_features
-        #[cfg_attr(doc_cfg, doc(cfg(feature = "extra-traits")))]
         impl Hash for #ident {
             fn hash<H>(&self, #hasher: &mut H)
             where