Unify item relative path computation in one function

Author: GuillaumeGomez

src/librustdoc/clean/inline.rs

@@ -191,15 +191,28 @@ pub(crate) fn load_attrs<'hir>(cx: &DocContext<'hir>, did: DefId) -> &'hir [ast:
     cx.tcx.get_attrs_unchecked(did)
 }
 
+pub(crate) fn item_relative_path(tcx: TyCtxt<'_>, def_id: DefId) -> Vec<Symbol> {
+    tcx.def_path(def_id)
+        .data
+        .into_iter()
+        .filter_map(|elem| {
+            // extern blocks (and a few others things) have an empty name.
+            match elem.data.get_opt_name() {
+                Some(s) if !s.is_empty() => Some(s),
+                _ => None,
+            }
+        })
+        .collect()
+}
+
 /// Record an external fully qualified name in the external_paths cache.
 ///
 /// These names are used later on by HTML rendering to generate things like
 /// source links back to the original item.
 pub(crate) fn record_extern_fqn(cx: &mut DocContext<'_>, did: DefId, kind: ItemType) {
     let crate_name = cx.tcx.crate_name(did.krate);
 
-    let relative =
-        cx.tcx.def_path(did).data.into_iter().filter_map(|elem| elem.data.get_opt_name());
+    let relative = item_relative_path(cx.tcx, did);
     let fqn = if let ItemType::Macro = kind {
         // Check to see if it is a macro 2.0 or built-in macro
         if matches!(
@@ -210,7 +223,7 @@ pub(crate) fn record_extern_fqn(cx: &mut DocContext<'_>, did: DefId, kind: ItemT
         ) {
             once(crate_name).chain(relative).collect()
         } else {
-            vec![crate_name, relative.last().expect("relative was empty")]
+            vec![crate_name, *relative.last().expect("relative was empty")]
         }
     } else {
         once(crate_name).chain(relative).collect()

src/librustdoc/html/format.rs

@@ -586,18 +586,7 @@ fn generate_macro_def_id_path(
     let crate_name = tcx.crate_name(def_id.krate);
     let cache = cx.cache();
 
-    let fqp: Vec<Symbol> = tcx
-        .def_path(def_id)
-        .data
-        .into_iter()
-        .filter_map(|elem| {
-            // extern blocks (and a few others things) have an empty name.
-            match elem.data.get_opt_name() {
-                Some(s) if !s.is_empty() => Some(s),
-                _ => None,
-            }
-        })
-        .collect();
+    let fqp = clean::inline::item_relative_path(tcx, def_id);
     let mut relative = fqp.iter().copied();
     let cstore = CStore::from_tcx(tcx);
     // We need this to prevent a `panic` when this function is used from intra doc links...
@@ -675,18 +664,7 @@ fn generate_item_def_id_path(
         .map(|adt| adt.did())
         .unwrap_or(def_id);
 
-    let relative: Vec<Symbol> = tcx
-        .def_path(def_id)
-        .data
-        .into_iter()
-        .filter_map(|elem| {
-            // extern blocks (and a few others things) have an empty name.
-            match elem.data.get_opt_name() {
-                Some(s) if !s.is_empty() => Some(s),
-                _ => None,
-            }
-        })
-        .collect();
+    let relative = clean::inline::item_relative_path(tcx, def_id);
     let fqp: Vec<Symbol> = once(crate_name).chain(relative).collect();
 
     let shortty = tcx.def_kind(def_id).into();