Fix scip crate symbol name

Author: darichey

src/tools/rust-analyzer/crates/ide/src/moniker.rs

@@ -289,7 +289,10 @@ fn def_to_non_local_moniker(
     definition: Definition,
     from_crate: Crate,
 ) -> Option<Moniker> {
-    let module = definition.module(db)?;
+    let module = match definition {
+        Definition::Module(module) if module.is_crate_root() => module,
+        _ => definition.module(db)?,
+    };
     let krate = module.krate();
     let edition = krate.edition(db);
 
@@ -322,12 +325,18 @@ fn def_to_non_local_moniker(
                         name: name.display(db, edition).to_string(),
                         desc: def_to_kind(db, def).into(),
                     });
-                } else if reverse_description.is_empty() {
-                    // Don't allow the last descriptor to be absent.
-                    return None;
                 } else {
                     match def {
-                        Definition::Module(module) if module.is_crate_root() => {}
+                        Definition::Module(module) if module.is_crate_root() => {
+                            // only include `crate` namespace by itself because we prefer
+                            // `rust-analyzer cargo foo . bar/` over `rust-analyzer cargo foo . crate/bar/`
+                            if reverse_description.is_empty() {
+                                reverse_description.push(MonikerDescriptor {
+                                    name: "crate".to_owned(),
+                                    desc: MonikerDescriptorKind::Namespace,
+                                });
+                            }
+                        }
                         _ => {
                             tracing::error!(?def, "Encountered enclosing definition with no name");
                         }
@@ -340,6 +349,9 @@ fn def_to_non_local_moniker(
         };
         def = next_def;
     }
+    if reverse_description.is_empty() {
+        return None;
+    }
     reverse_description.reverse();
     let description = reverse_description;