Implement type inference for enum variants

crates/ra_ide_api/src/completion/complete_path.rs

@@ -21,14 +21,20 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) -> C
                     .add_to(acc)
             });
         }
-        hir::Def::Enum(e) => e
-            .variants(ctx.db)?
-            .into_iter()
-            .for_each(|(name, _variant)| {
-                CompletionItem::new(CompletionKind::Reference, name.to_string())
-                    .kind(CompletionItemKind::EnumVariant)
-                    .add_to(acc)
-            }),
+        hir::Def::Enum(e) => {
+            e.variants(ctx.db)?
+                .unwrap_or(vec![])
+                .into_iter()
+                .for_each(|variant| {
+                    let variant_name = variant.name(ctx.db);
+
+                    if let Ok(Some(name)) = variant_name {
+                        CompletionItem::new(CompletionKind::Reference, name.to_string())
+                            .kind(CompletionItemKind::EnumVariant)
+                            .add_to(acc)
+                    }
+                })
+        }
         _ => return Ok(()),
     };
     Ok(())