From adfa0393049d385115517632b68b4e3ae330a941 Mon Sep 17 00:00:00 2001
From: takeokunn <bararararatty@gmail.com>
Date: Sat, 14 Feb 2026 18:13:09 +0900
Subject: [PATCH] feat(code-action): add quickfix to remove empty inherit (#755
 Split 16)

Mark DK_EmptyInherit diagnostic as isPreferred in the code action
handler so that editors surface the existing "remove `inherit` keyword"
fix as a preferred quickfix.

Closes part of #466.
---
 nixd/lib/Controller/CodeAction.cpp            |   1 +
 .../empty-inherit/empty-inherit.md            | 107 ++++++++++++++++++
 2 files changed, 108 insertions(+)
 create mode 100644 nixd/tools/nixd/test/code-action/empty-inherit/empty-inherit.md

diff --git a/nixd/lib/Controller/CodeAction.cpp b/nixd/lib/Controller/CodeAction.cpp
index 6e737116f..d1731cdba 100644
--- a/nixd/lib/Controller/CodeAction.cpp
+++ b/nixd/lib/Controller/CodeAction.cpp
@@ -51,6 +51,7 @@ void Controller::onCodeAction(const lspserver::CodeActionParams &Params,
         bool IsPreferred = false;
         switch (D.kind()) {
         case nixf::Diagnostic::DK_UnusedDefLet:
+        case nixf::Diagnostic::DK_EmptyInherit:
           IsPreferred = true;
           break;
         default:
diff --git a/nixd/tools/nixd/test/code-action/empty-inherit/empty-inherit.md b/nixd/tools/nixd/test/code-action/empty-inherit/empty-inherit.md
new file mode 100644
index 000000000..080720a09
--- /dev/null
+++ b/nixd/tools/nixd/test/code-action/empty-inherit/empty-inherit.md
@@ -0,0 +1,107 @@
+# RUN: nixd --lit-test < %s | FileCheck %s
+
+Test that `inherit;` (empty inherit) gets a quickfix to remove it.
+
+<-- initialize(0)
+
+```json
+{
+   "jsonrpc":"2.0",
+   "id":0,
+   "method":"initialize",
+   "params":{
+      "processId":123,
+      "rootPath":"",
+      "capabilities":{
+      },
+      "trace":"off"
+   }
+}
+```
+
+
+<-- textDocument/didOpen
+
+```nix file:///empty-inherit.nix
+{ inherit; }
+```
+
+<-- textDocument/codeAction(1)
+
+
+```json
+{
+   "jsonrpc":"2.0",
+   "id":1,
+   "method":"textDocument/codeAction",
+   "params":{
+      "textDocument":{
+         "uri":"file:///empty-inherit.nix"
+      },
+      "range":{
+         "start":{
+            "line": 0,
+            "character":2
+         },
+         "end":{
+            "line":0,
+            "character":9
+         }
+      },
+      "context":{
+         "diagnostics":[],
+         "triggerKind":2
+      }
+   }
+}
+```
+
+The action removes both `inherit` and `;`, producing `{  }`.
+
+```
+     CHECK:   "id": 1,
+CHECK-NEXT:   "jsonrpc": "2.0",
+CHECK-NEXT:   "result": [
+CHECK-NEXT:     {
+CHECK-NEXT:       "edit": {
+CHECK-NEXT:         "changes": {
+CHECK-NEXT:           "file:///empty-inherit.nix": [
+CHECK-NEXT:             {
+CHECK-NEXT:               "newText": "",
+CHECK-NEXT:               "range": {
+CHECK-NEXT:                 "end": {
+CHECK-NEXT:                   "character": 9,
+CHECK-NEXT:                   "line": 0
+CHECK-NEXT:                 },
+CHECK-NEXT:                 "start": {
+CHECK-NEXT:                   "character": 2,
+CHECK-NEXT:                   "line": 0
+CHECK-NEXT:                 }
+CHECK-NEXT:               }
+CHECK-NEXT:             },
+CHECK-NEXT:             {
+CHECK-NEXT:               "newText": "",
+CHECK-NEXT:               "range": {
+CHECK-NEXT:                 "end": {
+CHECK-NEXT:                   "character": 10,
+CHECK-NEXT:                   "line": 0
+CHECK-NEXT:                 },
+CHECK-NEXT:                 "start": {
+CHECK-NEXT:                   "character": 9,
+CHECK-NEXT:                   "line": 0
+CHECK-NEXT:                 }
+CHECK-NEXT:               }
+CHECK-NEXT:             }
+CHECK-NEXT:           ]
+CHECK-NEXT:         }
+CHECK-NEXT:       },
+CHECK-NEXT:       "isPreferred": true,
+CHECK-NEXT:       "kind": "quickfix",
+CHECK-NEXT:       "title": "remove `inherit` keyword"
+CHECK-NEXT:     }
+CHECK-NEXT:   ]
+```
+
+```json
+{"jsonrpc":"2.0","method":"exit"}
+```