From 0ebaa5146523409f76a5cdff4887f31cce43e17b Mon Sep 17 00:00:00 2001
From: Connor Pearson <cjpearson@users.noreply.github.com>
Date: Fri, 7 Mar 2025 12:32:08 +0100
Subject: [PATCH] fix(nuxt): apply ignore rules to nitro `devStorage` (#31233)

---
 packages/nuxt/src/core/nitro.ts | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/packages/nuxt/src/core/nitro.ts b/packages/nuxt/src/core/nitro.ts
index e552ffad67..da3ea0250b 100644
--- a/packages/nuxt/src/core/nitro.ts
+++ b/packages/nuxt/src/core/nitro.ts
@@ -6,7 +6,7 @@ import { createRouter as createRadixRouter, exportMatcher, toRouteMatcher } from
 import { joinURL, withTrailingSlash } from 'ufo'
 import { build, copyPublicAssets, createDevServer, createNitro, prepare, prerender, scanHandlers, writeTypes } from 'nitropack'
 import type { Nitro, NitroConfig, NitroOptions } from 'nitropack'
-import { findPath, logger, resolveAlias, resolveIgnorePatterns, resolveNuxtModule } from '@nuxt/kit'
+import { createIsIgnored, findPath, logger, resolveAlias, resolveIgnorePatterns, resolveNuxtModule } from '@nuxt/kit'
 import escapeRE from 'escape-string-regexp'
 import { defu } from 'defu'
 import { dynamicEventHandler } from 'h3'
@@ -428,6 +428,28 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
     }),
   )
 
+  // Apply Nuxt's ignore configuration to the root and src unstorage mounts
+  // created by Nitro. This ensures that the unstorage watcher will use the
+  // same ignore list as Nuxt's watcher and can reduce unneccesary file handles.
+  const isIgnored = createIsIgnored(nuxt)
+  nitroConfig.devStorage ??= {}
+  nitroConfig.devStorage.root ??= {
+    driver: 'fs',
+    readOnly: true,
+    base: nitroConfig.rootDir,
+    watchOptions: {
+      ignored: [isIgnored],
+    },
+  }
+  nitroConfig.devStorage.src ??= {
+    driver: 'fs',
+    readOnly: true,
+    base: nitroConfig.srcDir,
+    watchOptions: {
+      ignored: [isIgnored],
+    },
+  }
+
   // Extend nitro config with hook
   await nuxt.callHook('nitro:config', nitroConfig)