fix hover function

Author: xuhuanzy

crates/emmylua_ls/src/handlers/hover/build_hover.rs

@@ -160,7 +160,9 @@ fn build_decl_hover(
             builder.set_location_path(member);
         }
 
-        builder.add_signature_params_rets_description(typ);
+        // `typ`此时可能是泛型实例化后的类型, 所以我们需要从member获取原始类型
+        builder
+            .add_signature_params_rets_description(builder.semantic_model.get_type(decl_id.into()));
     } else {
         if typ.is_const() {
             let const_value = hover_const_type(db, &typ);
@@ -245,7 +247,10 @@ fn build_member_hover(
 
         builder.set_location_path(Some(&member));
 
-        builder.add_signature_params_rets_description(typ);
+        // `typ`此时可能是泛型实例化后的类型, 所以我们需要从member获取原始类型
+        builder.add_signature_params_rets_description(
+            builder.semantic_model.get_type(member.get_id().into()),
+        );
     } else {
         if typ.is_const() {
             let const_value = hover_const_type(db, &typ);

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

@@ -426,6 +426,7 @@ mod tests {
             },
         ));
     }
+
     #[test]
     fn test_other_file_function() {
         let mut ws = ProviderVirtualWorkspace::new();
@@ -449,4 +450,32 @@ mod tests {
             },
         ));
     }
+
+    #[test]
+    fn test_hover_generic_function_params_description() {
+        let mut ws = ProviderVirtualWorkspace::new();
+        ws.def_file(
+            "a.lua",
+            r#"
+                ---@class RingBuffer<T>
+                local RingBuffer = {}
+
+                ---@param index integer 索引
+                ---@return T? item
+                function RingBuffer:get(index)
+                end
+
+            "#,
+        );
+        assert!(ws.check_hover(
+            r#"
+                ---@type RingBuffer<string>
+                local RingBuffer
+                RingBuffer:<??>get(1)
+            "#,
+            VirtualHoverResult {
+                value: "```lua\n(method) RingBuffer:get(index: integer) -> string?\n```\n\n---\n\n@*param* `index` — 索引".to_string(),
+            },
+        ));
+    }
 }

crates/emmylua_ls/src/handlers/test_lib/mod.rs

@@ -159,7 +159,7 @@ impl ProviderVirtualWorkspace {
         // dbg!(&value);
         if value != expect.value {
             eprintln!(
-                "Hover content does not match expected value left: {value},\nright: {}",
+                "Hover content does not match expected value \nleft: {value},\nright: {}",
                 expect.value
             );
             return false;