diff --git a/packages/kit/src/components.ts b/packages/kit/src/components.ts
index 49bc6d91e2..1257a6a68d 100644
--- a/packages/kit/src/components.ts
+++ b/packages/kit/src/components.ts
@@ -55,7 +55,7 @@ export async function addComponent (opts: AddComponentOptions) {
   nuxt.hook('components:extend', (components: Component[]) => {
     const existingComponentIndex = components.findIndex(c => (c.pascalName === component.pascalName || c.kebabName === component.kebabName) && c.mode === component.mode)
     if (existingComponentIndex !== -1) {
-      const existingComponent = components[existingComponentIndex]
+      const existingComponent = components[existingComponentIndex]!
       const existingPriority = existingComponent.priority ?? 0
       const newPriority = component.priority ?? 0
 
diff --git a/packages/kit/src/ignore.ts b/packages/kit/src/ignore.ts
index 9dcdc32cf2..dc18508a06 100644
--- a/packages/kit/src/ignore.ts
+++ b/packages/kit/src/ignore.ts
@@ -50,7 +50,7 @@ export function resolveIgnorePatterns (relativePath?: string): string[] {
     // Map ignore patterns based on if they start with * or !*
     return ignorePatterns.map((p) => {
       const [_, negation = '', pattern] = p.match(NEGATION_RE) || []
-      if (pattern[0] === '*') {
+      if (pattern && pattern[0] === '*') {
         return p
       }
       return negation + relative(relativePath, resolve(nuxt.options.rootDir, pattern || p))
@@ -73,7 +73,7 @@ export function resolveGroupSyntax (group: string): string[] {
     groups = groups.flatMap((group) => {
       const [head, ...tail] = group.split('{')
       if (tail.length) {
-        const [body, ...rest] = tail.join('{').split('}')
+        const [body = '', ...rest] = tail.join('{').split('}')
         return body.split(',').map(part => `${head}${part}${rest.join('')}`)
       }
 
diff --git a/packages/kit/src/layout.ts b/packages/kit/src/layout.ts
index bf86c443c9..c159cd4a63 100644
--- a/packages/kit/src/layout.ts
+++ b/packages/kit/src/layout.ts
@@ -29,7 +29,7 @@ export function addLayout (this: any, template: NuxtTemplate | string, name?: st
   // Nuxt 3 adds layouts on app
   nuxt.hook('app:templates', (app) => {
     if (layoutName in app.layouts) {
-      const relativePath = relative(nuxt.options.srcDir, app.layouts[layoutName].file)
+      const relativePath = relative(nuxt.options.srcDir, app.layouts[layoutName]!.file)
       return logger.warn(
         `Not overriding \`${layoutName}\` (provided by \`~/${relativePath}\`) with \`${src || filename}\`.`,
       )
diff --git a/packages/kit/src/pages.ts b/packages/kit/src/pages.ts
index 04c7592a55..f3c9aa6b9c 100644
--- a/packages/kit/src/pages.ts
+++ b/packages/kit/src/pages.ts
@@ -51,7 +51,7 @@ export function addRouteMiddleware (input: NuxtMiddleware | NuxtMiddleware[], op
     for (const middleware of middlewares) {
       const find = app.middleware.findIndex(item => item.name === middleware.name)
       if (find >= 0) {
-        const foundPath = app.middleware[find].path
+        const foundPath = app.middleware[find]!.path
         if (foundPath === middleware.path) { continue }
         if (options.override === true) {
           app.middleware[find] = { ...middleware }
diff --git a/packages/kit/src/resolve.ts b/packages/kit/src/resolve.ts
index b170210efe..31ae08d2ed 100644
--- a/packages/kit/src/resolve.ts
+++ b/packages/kit/src/resolve.ts
@@ -174,7 +174,7 @@ export async function resolveNuxtModule (base: string, paths: string[]): Promise
 
   for (const path of paths) {
     if (path.startsWith(base)) {
-      resolved.push(path.split('/index.ts')[0])
+      resolved.push(path.split('/index.ts')[0]!)
     } else {
       const resolvedPath = await resolver.resolvePath(path)
       resolved.push(resolvedPath.slice(0, resolvedPath.lastIndexOf(path) + path.length))
diff --git a/packages/kit/src/template.ts b/packages/kit/src/template.ts
index 8e729c2f20..77dc044f9b 100644
--- a/packages/kit/src/template.ts
+++ b/packages/kit/src/template.ts
@@ -228,10 +228,10 @@ export async function _generateTypes (nuxt: Nuxt) {
     if (excludedAlias.some(re => re.test(alias))) {
       continue
     }
-    let absolutePath = resolve(basePath, aliases[alias])
+    let absolutePath = resolve(basePath, aliases[alias]!)
     let stats = await fsp.stat(absolutePath).catch(() => null /* file does not exist */)
     if (!stats) {
-      const resolvedModule = await tryResolveModule(aliases[alias], nuxt.options.modulesDir)
+      const resolvedModule = await tryResolveModule(aliases[alias]!, nuxt.options.modulesDir)
       if (resolvedModule) {
         absolutePath = resolvedModule
         stats = await fsp.stat(resolvedModule).catch(() => null)
@@ -251,7 +251,7 @@ export async function _generateTypes (nuxt: Nuxt) {
         // remove extension
         ? relativePath.replace(/\b\.\w+$/g, '')
         // non-existent file probably shouldn't be resolved
-        : aliases[alias]
+        : aliases[alias]!
 
       tsConfig.compilerOptions.paths[alias] = [path]
 
@@ -334,7 +334,7 @@ function renderAttrs (obj: Record<string, string>) {
   return attrs.join(' ')
 }
 
-function renderAttr (key: string, value: string) {
+function renderAttr (key: string, value?: string) {
   return value ? `${key}="${value}"` : ''
 }
 
diff --git a/packages/ui-templates/lib/render.ts b/packages/ui-templates/lib/render.ts
index c9d5986c4f..d81ffe873c 100644
--- a/packages/ui-templates/lib/render.ts
+++ b/packages/ui-templates/lib/render.ts
@@ -136,9 +136,14 @@ export const RenderPlugin = () => {
           }
           return lastChar || ''
         }).replace(/@media[^{]*\{\}/g, '')
-        const inlineScripts = Array.from(html.matchAll(/<script>([\s\S]*?)<\/script>/g))
-          .map(block => block[1])
-          .filter(i => !i.includes('const t=document.createElement("link")'))
+
+        const inlineScripts: string[] = []
+        for (const [_, i] of html.matchAll(/<script>([\s\S]*?)<\/script>/g)) {
+          if (i && !i.includes('const t=document.createElement("link")')) {
+            inlineScripts.push(i)
+          }
+        }
+
         const props = genObjectFromRawEntries(Object.entries({ ...genericMessages, ...messages }).map(([key, value]) => [key, {
           type: typeof value === 'string' ? 'String' : typeof value === 'number' ? 'Number' : typeof value === 'boolean' ? 'Boolean' : 'undefined',
           default: JSON.stringify(value),
diff --git a/packages/vite/src/plugins/analyze.ts b/packages/vite/src/plugins/analyze.ts
index ddb923f244..edecf536c7 100644
--- a/packages/vite/src/plugins/analyze.ts
+++ b/packages/vite/src/plugins/analyze.ts
@@ -16,10 +16,10 @@ export function analyzePlugin (ctx: ViteBuildContext): Plugin[] {
       async generateBundle (_opts, outputBundle) {
         for (const _bundleId in outputBundle) {
           const bundle = outputBundle[_bundleId]
-          if (bundle.type !== 'chunk') { continue }
+          if (!bundle || bundle.type !== 'chunk') { continue }
           const minifiedModuleEntryPromises: Array<Promise<[string, RenderedModule]>> = []
           for (const moduleId in bundle.modules) {
-            const module = bundle.modules[moduleId]
+            const module = bundle.modules[moduleId]!
             minifiedModuleEntryPromises.push(
               transform(module.code || '', { minify: true })
                 .then(result => [moduleId, { ...module, code: result.code }]),
diff --git a/packages/vite/src/plugins/composable-keys.ts b/packages/vite/src/plugins/composable-keys.ts
index af967c9eb7..0b6e897f15 100644
--- a/packages/vite/src/plugins/composable-keys.ts
+++ b/packages/vite/src/plugins/composable-keys.ts
@@ -17,7 +17,7 @@ interface ComposableKeysOptions {
   composables: Array<{ name: string, source?: string | RegExp, argumentLength: number }>
 }
 
-const stringTypes = ['Literal', 'TemplateLiteral']
+const stringTypes: Array<string | undefined> = ['Literal', 'TemplateLiteral']
 const NUXT_LIB_RE = /node_modules\/(?:nuxt|nuxt3|nuxt-nightly)\//
 const SUPPORTED_EXT_RE = /\.(?:m?[jt]sx?|vue)/
 
@@ -182,7 +182,7 @@ class ScopeTracker {
   leaveScope () {
     this.scopeIndexStack.pop()
     this.curScopeKey = this.getKey()
-    this.scopeIndexStack[this.scopeIndexStack.length - 1]++
+    this.scopeIndexStack[this.scopeIndexStack.length - 1]!++
   }
 }
 
@@ -255,9 +255,9 @@ export function detectImportNames (code: string, composableMeta: Record<string,
   for (const i of findStaticImports(code)) {
     if (NUXT_IMPORT_RE.test(i.specifier)) { continue }
 
-    const { namedImports, defaultImport, namespacedImport } = parseStaticImport(i)
-    for (const name in namedImports || {}) {
-      addName(namedImports![name], i.specifier)
+    const { namedImports = {}, defaultImport, namespacedImport } = parseStaticImport(i)
+    for (const name in namedImports) {
+      addName(namedImports[name]!, i.specifier)
     }
     if (defaultImport) {
       addName(defaultImport, i.specifier)
diff --git a/packages/vite/src/plugins/public-dirs.ts b/packages/vite/src/plugins/public-dirs.ts
index 379d451819..39e6b46b85 100644
--- a/packages/vite/src/plugins/public-dirs.ts
+++ b/packages/vite/src/plugins/public-dirs.ts
@@ -38,7 +38,7 @@ export const VitePublicDirsPlugin = createUnplugin((options: { sourcemap?: boole
         const s = new MagicString(code)
         const q = code.match(/(?<= = )['"`]/)?.[0] || '"'
         for (const [full, url] of code.matchAll(CSS_URL_RE)) {
-          if (resolveFromPublicAssets(url)) {
+          if (url && resolveFromPublicAssets(url)) {
             s.replace(full, `url(${q} + publicAssetsURL(${q}${url}${q}) + ${q})`)
           }
         }
@@ -53,13 +53,13 @@ export const VitePublicDirsPlugin = createUnplugin((options: { sourcemap?: boole
       },
       generateBundle (_outputOptions, bundle) {
         for (const file in bundle) {
-          const chunk = bundle[file]
+          const chunk = bundle[file]!
           if (!file.endsWith('.css') || chunk.type !== 'asset') { continue }
 
           let css = chunk.source.toString()
           let wasReplaced = false
           for (const [full, url] of css.matchAll(CSS_URL_RE)) {
-            if (resolveFromPublicAssets(url)) {
+            if (url && resolveFromPublicAssets(url)) {
               const relativeURL = relative(withLeadingSlash(dirname(file)), url)
               css = css.replace(full, `url(${relativeURL})`)
               wasReplaced = true
diff --git a/packages/vite/src/plugins/ssr-styles.ts b/packages/vite/src/plugins/ssr-styles.ts
index b1e785c6e9..cb7c520620 100644
--- a/packages/vite/src/plugins/ssr-styles.ts
+++ b/packages/vite/src/plugins/ssr-styles.ts
@@ -24,7 +24,7 @@ interface SSRStylePluginOptions {
 const SUPPORTED_FILES_RE = /\.(?:vue|(?:[cm]?j|t)sx?)$/
 
 export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
-  const cssMap: Record<string, { files: string[], inBundle: boolean }> = {}
+  const cssMap: Record<string, { files: string[], inBundle?: boolean }> = {}
   const idRefMap: Record<string, string> = {}
 
   const relativeToSrcDir = (path: string) => relative(options.srcDir, path)
@@ -63,7 +63,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
 
       const emitted: Record<string, string> = {}
       for (const file in cssMap) {
-        const { files, inBundle } = cssMap[file]
+        const { files, inBundle } = cssMap[file]!
         // File has been tree-shaken out of build (or there are no styles to inline)
         if (!files.length || !inBundle) { continue }
         const fileName = filename(file)
@@ -115,18 +115,19 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
         // 'Teleport' CSS chunks that made it into the bundle on the client side
         // to be inlined on server rendering
         if (options.mode === 'client') {
-          options.clientCSSMap[moduleId] ||= new Set()
+          const moduleMap = options.clientCSSMap[moduleId] ||= new Set()
           if (isCSS(moduleId)) {
             // Vue files can (also) be their own entrypoints as they are tracked separately
             if (isVue(moduleId)) {
-              options.clientCSSMap[moduleId].add(moduleId)
+              moduleMap.add(moduleId)
               const parent = moduleId.replace(/\?.+$/, '')
-              options.clientCSSMap[parent] ||= new Set()
-              options.clientCSSMap[parent].add(moduleId)
+              const parentMap = options.clientCSSMap[parent] ||= new Set()
+              parentMap.add(moduleId)
             }
             // This is required to track CSS in entry chunk
-            if (isEntry) {
-              options.clientCSSMap[chunk.facadeModuleId!].add(moduleId)
+            if (isEntry && chunk.facadeModuleId) {
+              const facadeMap = options.clientCSSMap[chunk.facadeModuleId] ||= new Set()
+              facadeMap.add(moduleId)
             }
           }
           continue
@@ -134,7 +135,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
 
         const relativePath = relativeToSrcDir(moduleId)
         if (relativePath in cssMap) {
-          cssMap[relativePath].inBundle = cssMap[relativePath].inBundle ?? ((isVue(moduleId) && relativeToSrcDir(moduleId)) || isEntry)
+          cssMap[relativePath]!.inBundle = cssMap[relativePath]!.inBundle ?? ((isVue(moduleId) && !!relativeToSrcDir(moduleId)) || isEntry)
         }
       }
 
@@ -146,7 +147,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
         // or include it here in the client build so it is emitted in the CSS.
         if (id === options.entry && (options.shouldInline === true || (typeof options.shouldInline === 'function' && options.shouldInline(id)))) {
           const s = new MagicString(code)
-          options.clientCSSMap[id] ||= new Set()
+          const idClientCSSMap = options.clientCSSMap[id] ||= new Set()
           if (!options.globalCSS.length) { return }
 
           for (const file of options.globalCSS) {
@@ -160,7 +161,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
               s.prepend(`${genImport(file)}\n`)
               continue
             }
-            options.clientCSSMap[id].add(resolved.id)
+            idClientCSSMap.add(resolved.id)
           }
           if (s.hasChanged()) {
             return {
@@ -184,7 +185,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
       }
 
       const relativeId = relativeToSrcDir(id)
-      cssMap[relativeId] = cssMap[relativeId] || { files: [] }
+      const idMap = cssMap[relativeId] ||= { files: [] }
 
       const emittedIds = new Set<string>()
 
@@ -208,7 +209,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
         })
 
         idRefMap[relativeToSrcDir(file)] = ref
-        cssMap[relativeId].files.push(ref)
+        idMap.files.push(ref)
       }
 
       if (!SUPPORTED_FILES_RE.test(pathname)) { return }
@@ -235,7 +236,7 @@ export function ssrStylesPlugin (options: SSRStylePluginOptions): Plugin {
         })
 
         idRefMap[relativeToSrcDir(resolved.id)] = ref
-        cssMap[relativeId].files.push(ref)
+        idMap.files.push(ref)
       }
     },
   }
diff --git a/packages/vite/src/plugins/type-check.ts b/packages/vite/src/plugins/type-check.ts
index 0ca1d4df85..f875187fc4 100644
--- a/packages/vite/src/plugins/type-check.ts
+++ b/packages/vite/src/plugins/type-check.ts
@@ -9,7 +9,7 @@ export function typeCheckPlugin (options: { sourcemap?: boolean } = {}): Plugin
     name: 'nuxt:type-check',
     configResolved (config) {
       const input = config.build.rollupOptions.input
-      if (input && typeof input !== 'string' && !Array.isArray(input)) {
+      if (input && typeof input !== 'string' && !Array.isArray(input) && input.entry) {
         entry = input.entry
       }
     },
diff --git a/packages/vite/src/plugins/virtual.ts b/packages/vite/src/plugins/virtual.ts
index c1887a7873..723958a6e7 100644
--- a/packages/vite/src/plugins/virtual.ts
+++ b/packages/vite/src/plugins/virtual.ts
@@ -39,7 +39,7 @@ export default function virtual (vfs: Record<string, string>): Plugin {
       const idNoPrefix = id.slice(PREFIX.length)
       if (idNoPrefix in vfs) {
         return {
-          code: vfs[idNoPrefix],
+          code: vfs[idNoPrefix] || '',
           map: null,
         }
       }
diff --git a/packages/vite/src/utils/transpile.ts b/packages/vite/src/utils/transpile.ts
index 8c60c1776a..8e9e2eb9da 100644
--- a/packages/vite/src/utils/transpile.ts
+++ b/packages/vite/src/utils/transpile.ts
@@ -10,7 +10,7 @@ interface Envs {
 
 export function transpile (envs: Envs): Array<string | RegExp> {
   const nuxt = useNuxt()
-  const transpile: Array<string | RegExp> = []
+  const transpile: RegExp[] = []
 
   for (let pattern of nuxt.options.build.transpile) {
     if (typeof pattern === 'function') {
diff --git a/packages/vite/src/vite.ts b/packages/vite/src/vite.ts
index b19b29ba0f..14526e828e 100644
--- a/packages/vite/src/vite.ts
+++ b/packages/vite/src/vite.ts
@@ -42,8 +42,8 @@ export const bundle: NuxtBuilder['bundle'] = async (nuxt) => {
       ...app.plugins.map(p => dirname(p.src)),
       ...app.middleware.map(m => dirname(m.path)),
       ...Object.values(app.layouts || {}).map(l => dirname(l.file)),
-      dirname(nuxt.apps.default.rootComponent!),
-      dirname(nuxt.apps.default.errorComponent!),
+      dirname(nuxt.apps.default!.rootComponent!),
+      dirname(nuxt.apps.default!.errorComponent!),
     ]),
   ].filter(d => d && existsSync(d))
 
@@ -184,7 +184,7 @@ export const bundle: NuxtBuilder['bundle'] = async (nuxt) => {
         clientCSSMap,
         chunksWithInlinedCSS,
         shouldInline: ctx.nuxt.options.features.inlineStyles,
-        components: ctx.nuxt.apps.default.components,
+        components: ctx.nuxt.apps.default!.components || [],
         globalCSS: ctx.nuxt.options.css,
         mode: isServer ? 'server' : 'client',
         entry: ctx.entry,
@@ -194,7 +194,7 @@ export const bundle: NuxtBuilder['bundle'] = async (nuxt) => {
     // Remove CSS entries for files that will have inlined styles
     ctx.nuxt.hook('build:manifest', (manifest) => {
       for (const key in manifest) {
-        const entry = manifest[key]
+        const entry = manifest[key]!
         const shouldRemoveCSS = chunksWithInlinedCSS.has(key) && !entry.isEntry
         if (entry.isEntry && chunksWithInlinedCSS.has(key)) {
           // @ts-expect-error internal key
diff --git a/test/basic.test.ts b/test/basic.test.ts
index b28f7a893a..b1369805f1 100644
--- a/test/basic.test.ts
+++ b/test/basic.test.ts
@@ -714,7 +714,7 @@ describe('nuxt links', () => {
     for (const selector of ['nuxt-link', 'router-link', 'link-with-trailing-slash', 'link-without-trailing-slash']) {
       data[selector] = []
       for (const match of html.matchAll(new RegExp(`href="([^"]*)"[^>]*class="[^"]*\\b${selector}\\b`, 'g'))) {
-        data[selector].push(match[1])
+        data[selector]!.push(match[1]!)
       }
     }
     expect(data).toMatchInlineSnapshot(`
@@ -1413,7 +1413,7 @@ describe('extends support', () => {
   describe('app', () => {
     it('extends foo/app/router.options & bar/app/router.options', async () => {
       const html: string = await $fetch<string>('/')
-      const routerLinkClasses = html.match(/href="\/" class="([^"]*)"/)?.[1].split(' ')
+      const routerLinkClasses = html.match(/href="\/" class="([^"]*)"/)![1]!.split(' ')
       expect(routerLinkClasses).toContain('foo-active-class')
       expect(routerLinkClasses).toContain('bar-exact-active-class')
     })
@@ -1456,7 +1456,7 @@ describe('nested suspense', () => {
     ['/suspense/sync-1/sync-1/', '/suspense/sync-2/async-1/'],
     ['/suspense/async-1/async-1/', '/suspense/async-2/async-1/'],
     ['/suspense/async-1/sync-1/', '/suspense/async-2/async-1/'],
-  ]).flatMap(([start, end]) => [
+  ] as const).flatMap(([start, end]) => [
     [start, end],
     [start, end + '?layout=custom'],
     [start + '?layout=custom', end],
@@ -1722,7 +1722,7 @@ describe.skipIf(isDev() || isWebpack)('inlining component styles', () => {
 
   it('should not include inlined CSS in generated CSS file', async () => {
     const html: string = await $fetch<string>('/styles')
-    const cssFiles = new Set([...html.matchAll(/<link [^>]*href="([^"]*\.css)">/g)].map(m => m[1]))
+    const cssFiles = new Set([...html.matchAll(/<link [^>]*href="([^"]*\.css)">/g)].map(m => m[1]!))
     let css = ''
     for (const file of cssFiles || []) {
       css += await $fetch<string>(file)
@@ -1973,7 +1973,7 @@ describe.skipIf(isDev())('dynamic paths', () => {
   it('should work with no overrides', async () => {
     const html: string = await $fetch<string>('/assets')
     for (const match of html.matchAll(/(href|src)="(.*?)"|url\(([^)]*)\)/g)) {
-      const url = match[2] || match[3]
+      const url = match[2] || match[3]!
       expect(url.startsWith('/_nuxt/') || isPublicFile('/', url)).toBeTruthy()
     }
   })
@@ -1982,10 +1982,10 @@ describe.skipIf(isDev())('dynamic paths', () => {
   it.skipIf(isWebpack)('adds relative paths to CSS', async () => {
     const html: string = await $fetch<string>('/assets')
     const urls = Array.from(html.matchAll(/(href|src)="(.*?)"|url\(([^)]*)\)/g)).map(m => m[2] || m[3])
-    const cssURL = urls.find(u => /_nuxt\/assets.*\.css$/.test(u))
+    const cssURL = urls.find(u => /_nuxt\/assets.*\.css$/.test(u!))
     expect(cssURL).toBeDefined()
     const css = await $fetch<string>(cssURL!)
-    const imageUrls = new Set(Array.from(css.matchAll(/url\(([^)]*)\)/g)).map(m => m[1].replace(/[-.]\w{8}\./g, '.')))
+    const imageUrls = new Set(Array.from(css.matchAll(/url\(([^)]*)\)/g)).map(m => m[1]!.replace(/[-.]\w{8}\./g, '.')))
     expect([...imageUrls]).toMatchInlineSnapshot(`
       [
         "./logo.svg",
@@ -2004,7 +2004,7 @@ describe.skipIf(isDev())('dynamic paths', () => {
 
     const html = await $fetch<string>('/foo/assets')
     for (const match of html.matchAll(/(href|src)="(.*?)"|url\(([^)]*)\)/g)) {
-      const url = match[2] || match[3]
+      const url = match[2] || match[3]!
       expect(url.startsWith('/foo/_other/') || isPublicFile('/foo/', url)).toBeTruthy()
     }
 
@@ -2020,7 +2020,7 @@ describe.skipIf(isDev())('dynamic paths', () => {
 
     const html = await $fetch<string>('/assets')
     for (const match of html.matchAll(/(href|src)="(.*?)"|url\(([^)]*)\)/g)) {
-      const url = match[2] || match[3]
+      const url = match[2] || match[3]!
       expect(url.startsWith('./_nuxt/') || isPublicFile('./', url)).toBeTruthy()
       expect(url.startsWith('./_nuxt/_nuxt')).toBeFalsy()
     }
@@ -2049,7 +2049,7 @@ describe.skipIf(isDev())('dynamic paths', () => {
 
     const html = await $fetch<string>('/foo/assets')
     for (const match of html.matchAll(/(href|src)="(.*?)"|url\(([^)]*)\)/g)) {
-      const url = match[2] || match[3]
+      const url = match[2] || match[3]!
       expect(url.startsWith('https://example.com/_cdn/') || isPublicFile('https://example.com/', url)).toBeTruthy()
     }
   })
@@ -2085,7 +2085,7 @@ describe('component islands', () => {
 
     result.html = result.html.replace(/ data-island-uid="[^"]*"/g, '')
     if (isDev()) {
-      result.head.link = result.head.link.filter(l => !l.href.includes('@nuxt+ui-templates') && (l.href.startsWith('_nuxt/components/islands/') && l.href.includes('_nuxt/components/islands/RouteComponent')))
+      result.head.link = result.head.link.filter(l => !l.href!.includes('@nuxt+ui-templates') && (l.href!.startsWith('_nuxt/components/islands/') && l.href!.includes('_nuxt/components/islands/RouteComponent')))
     }
 
     expect(result).toMatchInlineSnapshot(`
@@ -2107,7 +2107,7 @@ describe('component islands', () => {
       }),
     }))
     if (isDev()) {
-      result.head.link = result.head.link.filter(l => !l.href.includes('@nuxt+ui-templates') && (l.href.startsWith('_nuxt/components/islands/') && l.href.includes('_nuxt/components/islands/LongAsyncComponent')))
+      result.head.link = result.head.link.filter(l => !l.href!.includes('@nuxt+ui-templates') && (l.href!.startsWith('_nuxt/components/islands/') && l.href!.includes('_nuxt/components/islands/LongAsyncComponent')))
     }
     result.html = result.html.replaceAll(/ (data-island-uid|data-island-component)="([^"]*)"/g, '')
     expect(result).toMatchInlineSnapshot(`
@@ -2165,7 +2165,7 @@ describe('component islands', () => {
       }),
     }))
     if (isDev()) {
-      result.head.link = result.head.link.filter(l => !l.href.includes('@nuxt+ui-templates') && (l.href.startsWith('_nuxt/components/islands/') && l.href.includes('_nuxt/components/islands/AsyncServerComponent')))
+      result.head.link = result.head.link.filter(l => !l.href!.includes('@nuxt+ui-templates') && (l.href!.startsWith('_nuxt/components/islands/') && l.href!.includes('_nuxt/components/islands/AsyncServerComponent')))
     }
     result.props = {}
     result.components = {}
@@ -2190,7 +2190,7 @@ describe('component islands', () => {
     it('render server component with selective client hydration', async () => {
       const result = await $fetch<NuxtIslandResponse>('/__nuxt_island/ServerWithClient')
       if (isDev()) {
-        result.head.link = result.head.link.filter(l => !l.href.includes('@nuxt+ui-templates') && (l.href.startsWith('_nuxt/components/islands/') && l.href.includes('_nuxt/components/islands/AsyncServerComponent')))
+        result.head.link = result.head.link.filter(l => !l.href!.includes('@nuxt+ui-templates') && (l.href!.startsWith('_nuxt/components/islands/') && l.href!.includes('_nuxt/components/islands/AsyncServerComponent')))
       }
       const { components } = result
       result.components = {}
@@ -2211,13 +2211,13 @@ describe('component islands', () => {
         }
       `)
       expect(teleportsEntries).toHaveLength(1)
-      expect(teleportsEntries[0][0].startsWith('Counter-')).toBeTruthy()
-      expect(teleportsEntries[0][1].props).toMatchInlineSnapshot(`
+      expect(teleportsEntries[0]![0].startsWith('Counter-')).toBeTruthy()
+      expect(teleportsEntries[0]![1].props).toMatchInlineSnapshot(`
       {
         "multiplier": 1,
       }
     `)
-      expect(teleportsEntries[0][1].html).toMatchInlineSnapshot('"<div class="sugar-counter"> Sugar Counter 12 x 1 = 12 <button> Inc </button></div><!--teleport anchor-->"')
+      expect(teleportsEntries[0]![1].html).toMatchInlineSnapshot('"<div class="sugar-counter"> Sugar Counter 12 x 1 = 12 <button> Inc </button></div><!--teleport anchor-->"')
     })
   }
 
@@ -2235,10 +2235,10 @@ describe('component islands', () => {
     if (isDev()) {
       const fixtureDir = normalize(fileURLToPath(new URL('./fixtures/basic', import.meta.url)))
       for (const link of result.head.link) {
-        link.href = link.href.replace(fixtureDir, '/<rootDir>').replaceAll('//', '/')
-        link.key = link.key.replace(/-[a-z0-9]+$/i, '')
+        link.href = link.href!.replace(fixtureDir, '/<rootDir>').replaceAll('//', '/')
+        link.key = link.key!.replace(/-[a-z0-9]+$/i, '')
       }
-      result.head.link.sort((a, b) => b.href.localeCompare(a.href))
+      result.head.link.sort((a, b) => b.href!.localeCompare(a.href!))
     }
 
     // TODO: fix rendering of styles in webpack
@@ -2257,7 +2257,7 @@ describe('component islands', () => {
     } else if (isDev() && !isWebpack) {
       // TODO: resolve dev bug triggered by earlier fetch of /vueuse-head page
       // https://github.com/nuxt/nuxt/blob/main/packages/nuxt/src/core/runtime/nitro/renderer.ts#L139
-      result.head.link = result.head.link.filter(h => !h.href.includes('SharedComponent'))
+      result.head.link = result.head.link.filter(h => !h.href!.includes('SharedComponent'))
       expect(result.head).toMatchInlineSnapshot(`
         {
           "link": [
diff --git a/test/hmr.test.ts b/test/hmr.test.ts
index c1e8963cf9..7df468cfa1 100644
--- a/test/hmr.test.ts
+++ b/test/hmr.test.ts
@@ -108,7 +108,7 @@ if (process.env.TEST_ENV !== 'built' && !isWindows) {
       const resolveHmrId = async () => {
         const node = await page.$('#hmr-id')
         const text = await node?.innerText() || ''
-        return Number(text?.trim().split(':')[1].trim())
+        return Number(text.trim().split(':')[1]?.trim() || '')
       }
       const componentPath = join(fixturePath, 'components/islands/HmrComponent.vue')
       const triggerHmr = async () => fsp.writeFile(
diff --git a/test/utils.ts b/test/utils.ts
index 3ddbc487b4..d88d5fd063 100644
--- a/test/utils.ts
+++ b/test/utils.ts
@@ -107,17 +107,17 @@ export function parsePayload (payload: string) {
 }
 export function parseData (html: string) {
   if (!isRenderingJson) {
-    const { script } = html.match(/<script>(?<script>window.__NUXT__.*?)<\/script>/)?.groups || {}
+    const { script = '' } = html.match(/<script>(?<script>window.__NUXT__.*?)<\/script>/)?.groups || {}
     const _script = new Script(script)
     return {
       script: _script.runInContext(createContext({ window: {} })),
       attrs: {},
     }
   }
-  const { script, attrs } = html.match(/<script type="application\/json" id="__NUXT_DATA__"(?<attrs>[^>]+)>(?<script>.*?)<\/script>/)?.groups || {}
+  const { script, attrs = '' } = html.match(/<script type="application\/json" id="__NUXT_DATA__"(?<attrs>[^>]+)>(?<script>.*?)<\/script>/)?.groups || {}
   const _attrs: Record<string, string> = {}
   for (const attr of attrs.matchAll(/( |^)(?<key>[\w-]+)="(?<value>[^"]+)"/g)) {
-    _attrs[attr!.groups!.key] = attr!.groups!.value
+    _attrs[attr!.groups!.key!] = attr!.groups!.value!
   }
   return {
     script: parsePayload(script || ''),