rustdoc: rewrite stability inheritance as a pass

1 files changed, 12 insertions, 19 deletions

diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index d120e7f36eb..38276e4d20c 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -436,16 +436,9 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
             }
 
             clean::ImportItem(ref import) => {
-                let stab_tags = if let Some(import_def_id) = import.source.did {
-                    // Just need an item with the correct def_id and attrs
-                    let import_item =
-                        clean::Item { item_id: import_def_id.into(), ..(*myitem).clone() };
-
-                    let stab_tags = Some(extra_info_tags(&import_item, item, tcx).to_string());
-                    stab_tags
-                } else {
-                    None
-                };
+                let stab_tags = import.source.did.map_or_else(String::new, |import_def_id| {
+                    extra_info_tags(tcx, myitem, item, Some(import_def_id)).to_string()
+                });
 
                 w.write_str(ITEM_TABLE_ROW_OPEN);
                 let id = match import.kind {
@@ -454,7 +447,6 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                     }
                     clean::ImportKind::Glob => String::new(),
                 };
-                let stab_tags = stab_tags.unwrap_or_default();
                 let (stab_tags_before, stab_tags_after) = if stab_tags.is_empty() {
                     ("", "")
                 } else {
@@ -521,7 +513,7 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
                      {docs_before}{docs}{docs_after}",
                     name = EscapeBodyTextWithWbr(myitem.name.unwrap().as_str()),
                     visibility_and_hidden = visibility_and_hidden,
-                    stab_tags = extra_info_tags(myitem, item, tcx),
+                    stab_tags = extra_info_tags(tcx, myitem, item, None),
                     class = myitem.type_(),
                     unsafety_flag = unsafety_flag,
                     href = item_path(myitem.type_(), myitem.name.unwrap().as_str()),
@@ -544,9 +536,10 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
 /// Render the stability, deprecation and portability tags that are displayed in the item's summary
 /// at the module level.
 fn extra_info_tags<'a, 'tcx: 'a>(
+    tcx: TyCtxt<'tcx>,
     item: &'a clean::Item,
     parent: &'a clean::Item,
-    tcx: TyCtxt<'tcx>,
+    import_def_id: Option<DefId>,
 ) -> impl fmt::Display + 'a + Captures<'tcx> {
     display_fn(move |f| {
         fn tag_html<'a>(
@@ -564,18 +557,18 @@ fn extra_info_tags<'a, 'tcx: 'a>(
         }
 
         // The trailing space after each tag is to space it properly against the rest of the docs.
-        if let Some(depr) = &item.deprecation(tcx) {
+        let deprecation = import_def_id
+            .map_or_else(|| item.deprecation(tcx), |import_did| tcx.lookup_deprecation(import_did));
+        if let Some(depr) = deprecation {
             let message = if depr.is_in_effect() { "Deprecated" } else { "Deprecation planned" };
             write!(f, "{}", tag_html("deprecated", "", message))?;
         }
 
         // The "rustc_private" crates are permanently unstable so it makes no sense
         // to render "unstable" everywhere.
-        if item
-            .stability(tcx)
-            .as_ref()
-            .is_some_and(|s| s.is_unstable() && s.feature != sym::rustc_private)
-        {
+        let stability = import_def_id
+            .map_or_else(|| item.stability(tcx), |import_did| tcx.lookup_stability(import_did));
+        if stability.is_some_and(|s| s.is_unstable() && s.feature != sym::rustc_private) {
             write!(f, "{}", tag_html("unstable", "", "Experimental"))?;
         }