From ebb6ecf558921cc3faedc303118769dbedf0cfb4 Mon Sep 17 00:00:00 2001
From: DACONLEEHANGYU <han-gyu@dacon.kr>
Date: Sun, 25 Jan 2026 22:44:26 +0900
Subject: [PATCH] fix(svelte-query): suppress false positive unused import
 warnings

Fixes #9740

Added rollup onwarn handler to suppress UNUSED_EXTERNAL_IMPORT warnings
for @tanstack/query-core imports. These warnings are false positives as
the imports (notifyManager, replaceEqualDeep) are actually used in the
compiled code but Rollup's tree-shaking analysis fails to detect this
in Svelte 5's runes context ($effect, $state, $derived).

The warning appeared during SvelteKit project builds mentioning:
- notifyManager (used in createMutation.svelte.ts)
- replaceEqualDeep (used in useMutationState.svelte.ts)
---
 packages/svelte-query/vite.config.ts | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/packages/svelte-query/vite.config.ts b/packages/svelte-query/vite.config.ts
index 1ed8e56135..6b910a56e4 100644
--- a/packages/svelte-query/vite.config.ts
+++ b/packages/svelte-query/vite.config.ts
@@ -17,6 +17,21 @@ export default defineConfig({
       },
     },
   },
+  build: {
+    rollupOptions: {
+      onwarn(warning, warn) {
+        // Suppress false positive "unused import" warnings from @tanstack/query-core
+        // These imports (notifyManager, replaceEqualDeep) are actually used in the code
+        if (
+          warning.code === 'UNUSED_EXTERNAL_IMPORT' &&
+          warning.message?.includes('@tanstack/query-core')
+        ) {
+          return
+        }
+        warn(warning)
+      },
+    },
+  },
   test: {
     name: packageJson.name,
     dir: './tests',