Merge pull request #840 from xuhuanzy/Generics

fix generic

Author: CppCXY

crates/emmylua_code_analysis/src/semantic/generic/instantiate_type/mod.rs

@@ -837,12 +837,28 @@ fn instantiate_mapped_type(
         }
 
         if !fields.is_empty() || !index_access.is_empty() {
+            // key 从 0 开始递增才被视为元组
             if constraint.is_tuple() {
-                let types = fields.into_iter().map(|(_, ty)| ty).collect();
-                // return LuaType::Variadic(VariadicType::Multi(types).into());
-                return LuaType::Tuple(
-                    LuaTupleType::new(types, LuaTupleStatus::InferResolve).into(),
-                );
+                let mut index = 0;
+                let mut is_tuple = true;
+                for (key, _) in &fields {
+                    if let LuaMemberKey::Integer(i) = key {
+                        if *i != index {
+                            is_tuple = false;
+                            break;
+                        }
+                        index += 1;
+                    } else {
+                        is_tuple = false;
+                        break;
+                    }
+                }
+                if is_tuple {
+                    let types = fields.into_iter().map(|(_, ty)| ty).collect();
+                    return LuaType::Tuple(
+                        LuaTupleType::new(types, LuaTupleStatus::InferResolve).into(),
+                    );
+                }
             }
             let field_map: HashMap<LuaMemberKey, LuaType> = fields.into_iter().collect();
             return LuaType::Object(LuaObjectType::new_with_fields(field_map, index_access).into());

crates/emmylua_ls/src/handlers/test/completion_test.rs

@@ -2158,4 +2158,38 @@ mod tests {
         ));
         Ok(())
     }
+
+    #[gtest]
+    fn test_generic_partial() -> Result<()> {
+        let mut ws = ProviderVirtualWorkspace::new();
+        ws.def(
+            r#"
+        ---@alias Partial<T> { [P in keyof T]?: T[P]; }
+        "#,
+        );
+        check!(ws.check_completion(
+            r#"
+            ---@class AA
+            ---@field a string
+            ---@field b number
+
+            ---@type Partial<AA>
+            local a = {}
+            a.<??>
+            "#,
+            vec![
+                VirtualCompletionItem {
+                    label: "a".to_string(),
+                    kind: CompletionItemKind::VARIABLE,
+                    ..Default::default()
+                },
+                VirtualCompletionItem {
+                    label: "b".to_string(),
+                    kind: CompletionItemKind::VARIABLE,
+                    ..Default::default()
+                }
+            ],
+        ));
+        Ok(())
+    }
 }