perf: extract regex patterns

packages/kit/src/components.ts

@@ -19,6 +19,7 @@ export type AddComponentOptions = { name: string, filePath: string } & Partial<E
 'shortPath' | 'async' | 'level' | 'import' | 'asyncImport'
 >>
 
+const COMPONENT_MODE_RE = /\.(server|client)(\.\w+)*$/
 /**
  * Register a component by its name and filePath.
  */
@@ -28,7 +29,7 @@ export async function addComponent (opts: AddComponentOptions) {
   nuxt.options.components = nuxt.options.components || []
 
   if (!opts.mode) {
-    const [, mode = 'all'] = opts.filePath.match(/\.(server|client)(\.\w+)*$/) || []
+    const [, mode = 'all'] = opts.filePath.match(COMPONENT_MODE_RE) || []
     opts.mode = mode as 'all' | 'client' | 'server'
   }
 

packages/kit/src/layout.ts

@@ -5,10 +5,11 @@ import { useNuxt } from './context'
 import { logger } from './logger'
 import { addTemplate } from './template'
 
+const LAYOUT_RE = /["']/g
 export function addLayout (template: NuxtTemplate | string, name?: string) {
   const nuxt = useNuxt()
   const { filename, src } = addTemplate(template)
-  const layoutName = kebabCase(name || parse(filename).name).replace(/["']/g, '')
+  const layoutName = kebabCase(name || parse(filename).name).replace(LAYOUT_RE, '')
 
   // Nuxt 3 adds layouts on app
   nuxt.hook('app:templates', (app) => {

packages/kit/src/nitro.ts

@@ -4,13 +4,14 @@ import { normalize } from 'pathe'
 import { useNuxt } from './context'
 import { toArray } from './utils'
 
+const HANDLER_METHOD_RE = /\.(get|head|patch|post|put|delete|connect|options|trace)(\.\w+)*$/
 /**
  * normalize handler object
  *
  */
 function normalizeHandlerMethod (handler: NitroEventHandler) {
   // retrieve method from handler file name
-  const [, method = undefined] = handler.handler.match(/\.(get|head|patch|post|put|delete|connect|options|trace)(\.\w+)*$/) || []
+  const [, method = undefined] = handler.handler.match(HANDLER_METHOD_RE) || []
   return {
     method: method as 'get' | 'head' | 'patch' | 'post' | 'put' | 'delete' | 'connect' | 'options' | 'trace' | undefined,
     ...handler,

packages/kit/src/plugin.ts

@@ -4,6 +4,7 @@ import { useNuxt } from './context'
 import { addTemplate } from './template'
 import { resolveAlias } from './resolve'
 
+const PLUGIN_MODE_RE = /\.(server|client)(\.\w+)*$/
 /**
  * Normalize a nuxt plugin object
  */
@@ -27,7 +28,7 @@ export function normalizePlugin (plugin: NuxtPlugin | string): NuxtPlugin {
     plugin.mode = 'server'
   }
   if (!plugin.mode) {
-    const [, mode = 'all'] = plugin.src.match(/\.(server|client)(\.\w+)*$/) || []
+    const [, mode = 'all'] = plugin.src.match(PLUGIN_MODE_RE) || []
     plugin.mode = mode as 'all' | 'client' | 'server'
   }
 

packages/kit/src/template.ts

@@ -123,6 +123,9 @@ export async function updateTemplates (options?: { filter?: (template: ResolvedN
   return await tryUseNuxt()?.hooks.callHook('builder:generateApp', options)
 }
 
+const EXTENSION_RE = /\b\.\w+$/g
+// Exclude bridge alias types to support Volar
+const excludedAlias = [/^@vue\/.*$/, /^#internal\/nuxt/]
 export async function _generateTypes (nuxt: Nuxt) {
   const rootDirWithSlash = withTrailingSlash(nuxt.options.rootDir)
   const relativeRootDir = relativeWithDot(nuxt.options.buildDir, nuxt.options.rootDir)
@@ -225,9 +228,6 @@ export async function _generateTypes (nuxt: Nuxt) {
 
   const aliases: Record<string, string> = nuxt.options.alias
 
-  // Exclude bridge alias types to support Volar
-  const excludedAlias = [/^@vue\/.*$/, /^#internal\/nuxt/]
-
   const basePath = tsConfig.compilerOptions!.baseUrl
     ? resolve(nuxt.options.buildDir, tsConfig.compilerOptions!.baseUrl)
     : nuxt.options.buildDir
@@ -260,7 +260,7 @@ export async function _generateTypes (nuxt: Nuxt) {
     } else {
       const path = stats?.isFile()
         // remove extension
-        ? relativePath.replace(/\b\.\w+$/g, '')
+        ? relativePath.replace(EXTENSION_RE, '')
         // non-existent file probably shouldn't be resolved
         : aliases[alias]!
 
@@ -289,7 +289,7 @@ export async function _generateTypes (nuxt: Nuxt) {
     tsConfig.compilerOptions!.paths[alias] = await Promise.all(paths.map(async (path: string) => {
       if (!isAbsolute(path)) { return path }
       const stats = await fsp.stat(path).catch(() => null /* file does not exist */)
-      return relativeWithDot(nuxt.options.buildDir, stats?.isFile() ? path.replace(/\b\.\w+$/g, '') /* remove extension */ : path)
+      return relativeWithDot(nuxt.options.buildDir, stats?.isFile() ? path.replace(EXTENSION_RE, '') /* remove extension */ : path)
     }))
   }
 
@@ -344,6 +344,7 @@ function renderAttr (key: string, value?: string) {
   return value ? `${key}="${value}"` : ''
 }
 
+const RELATIVE_WITH_DOT_RE = /^([^.])/
 function relativeWithDot (from: string, to: string) {
-  return relative(from, to).replace(/^([^.])/, './$1') || '.'
+  return relative(from, to).replace(RELATIVE_WITH_DOT_RE, './$1') || '.'
 }

packages/nuxt/src/app/components/nuxt-island.ts

@@ -22,6 +22,7 @@ const SSR_UID_RE = /data-island-uid="([^"]*)"/
 const DATA_ISLAND_UID_RE = /data-island-uid(="")?(?!="[^"])/g
 const SLOTNAME_RE = /data-island-slot="([^"]*)"/g
 const SLOT_FALLBACK_RE = / data-island-slot="([^"]*)"[^>]*>/g
+const ISLAND_SCOPE_ID_RE = /^<[^> ]*/
 
 let id = 1
 const getId = import.meta.client ? () => (id++).toString() : randomUUID
@@ -142,7 +143,7 @@ export default defineComponent({
       let html = ssrHTML.value
 
       if (props.scopeId) {
-        html = html.replace(/^<[^> ]*/, full => full + ' ' + props.scopeId)
+        html = html.replace(ISLAND_SCOPE_ID_RE, full => full + ' ' + props.scopeId)
       }
 
       if (import.meta.client && !canLoadClientComponent.value) {

packages/nuxt/src/app/components/nuxt-link.ts

@@ -521,11 +521,12 @@ function useObserver (): { observe: ObserveFn } | undefined {
   return _observer
 }
 
+const IS_2G_RE = /2g/
 function isSlowConnection () {
   if (import.meta.server) { return }
 
   // https://developer.mozilla.org/en-US/docs/Web/API/Navigator/connection
   const cn = (navigator as any).connection as { saveData: boolean, effectiveType: string } | null
-  if (cn && (cn.saveData || /2g/.test(cn.effectiveType))) { return true }
+  if (cn && (cn.saveData || IS_2G_RE.test(cn.effectiveType))) { return true }
   return false
 }

packages/nuxt/src/app/components/utils.ts

@@ -15,13 +15,16 @@ export const _wrapIf = (component: Component, props: any, slots: any) => {
   return { default: () => props ? h(component, props, slots) : slots.default?.() }
 }
 
+const ROUTE_KEY_PARENTHESES_RE = /(:\w+)\([^)]+\)/g
+const ROUTE_KEY_SYMBOLS_RE = /(:\w+)[?+*]/g
+const ROUTE_KEY_NORMAL_RE = /:\w+/g
 // TODO: consider refactoring into single utility
 // See https://github.com/nuxt/nuxt/tree/main/packages/nuxt/src/pages/runtime/utils.ts#L8-L19
 function generateRouteKey (route: RouteLocationNormalized) {
   const source = route?.meta.key ?? route.path
-    .replace(/(:\w+)\([^)]+\)/g, '$1')
+    .replace(ROUTE_KEY_PARENTHESES_RE, '$1')
-    .replace(/(:\w+)[?+*]/g, '$1')
+    .replace(ROUTE_KEY_SYMBOLS_RE, '$1')
-    .replace(/:\w+/g, r => route.params[r.slice(1)]?.toString() || '')
+    .replace(ROUTE_KEY_NORMAL_RE, r => route.params[r.slice(1)]?.toString() || '')
   return typeof source === 'function' ? source(route) : source
 }
 

packages/nuxt/src/app/composables/router.ts

@@ -114,6 +114,7 @@ export interface NavigateToOptions {
   open?: OpenOptions
 }
 
+const QUOTE_RE = /"/g
 /** @since 3.0.0 */
 export const navigateTo = (to: RouteLocationRaw | undefined | null, options?: NavigateToOptions): Promise<void | NavigationFailure | false> | false | void | RouteLocationRaw => {
   if (!to) {
@@ -166,7 +167,7 @@ export const navigateTo = (to: RouteLocationRaw | undefined | null, options?: Na
       const redirect = async function (response: any) {
         // TODO: consider deprecating in favour of `app:rendered` and removing
         await nuxtApp.callHook('app:redirected')
-        const encodedLoc = location.replace(/"/g, '%22')
+        const encodedLoc = location.replace(QUOTE_RE, '%22')
         const encodedHeader = encodeURL(location, isExternalHost)
 
         nuxtApp.ssrContext!._renderResponse = {

packages/nuxt/src/components/module.ts

@@ -16,11 +16,13 @@ import { ComponentNamePlugin } from './plugins/component-names'
 
 const isPureObjectOrString = (val: any) => (!Array.isArray(val) && typeof val === 'object') || typeof val === 'string'
 const isDirectory = (p: string) => { try { return statSync(p).isDirectory() } catch { return false } }
+const SLASH_SEPARATOR_RE = /[\\/]/
 function compareDirByPathLength ({ path: pathA }: { path: string }, { path: pathB }: { path: string }) {
-  return pathB.split(/[\\/]/).filter(Boolean).length - pathA.split(/[\\/]/).filter(Boolean).length
+  return pathB.split(SLASH_SEPARATOR_RE).filter(Boolean).length - pathA.split(SLASH_SEPARATOR_RE).filter(Boolean).length
 }
 
 const DEFAULT_COMPONENTS_DIRS_RE = /\/components(?:\/(?:global|islands))?$/
+const STARTER_DOT_RE = /^\./g
 
 export type getComponentsT = (mode?: 'client' | 'server' | 'all') => Component[]
 
@@ -89,7 +91,7 @@ export default defineNuxtModule<ComponentsOptions>({
         const dirOptions: ComponentsDir = typeof dir === 'object' ? dir : { path: dir }
         const dirPath = resolveAlias(dirOptions.path)
         const transpile = typeof dirOptions.transpile === 'boolean' ? dirOptions.transpile : 'auto'
-        const extensions = (dirOptions.extensions || nuxt.options.extensions).map(e => e.replace(/^\./g, ''))
+        const extensions = (dirOptions.extensions || nuxt.options.extensions).map(e => e.replace(STARTER_DOT_RE, ''))
 
         const present = isDirectory(dirPath)
         if (!present && !DEFAULT_COMPONENTS_DIRS_RE.test(dirOptions.path)) {

packages/nuxt/src/components/plugins/client-fallback-auto-id.ts

@@ -12,6 +12,7 @@ interface LoaderOptions {
 }
 const CLIENT_FALLBACK_RE = /<(?:NuxtClientFallback|nuxt-client-fallback)(?: [^>]*)?>/
 const CLIENT_FALLBACK_GLOBAL_RE = /<(NuxtClientFallback|nuxt-client-fallback)( [^>]*)?>/g
+const UID_RE = / :?uid=/
 export const ClientFallbackAutoIdPlugin = (options: LoaderOptions) => createUnplugin(() => {
   const exclude = options.transform?.exclude || []
   const include = options.transform?.include || []
@@ -37,7 +38,7 @@ export const ClientFallbackAutoIdPlugin = (options: LoaderOptions) => createUnpl
 
       s.replace(CLIENT_FALLBACK_GLOBAL_RE, (full, name, attrs) => {
         count++
-        if (/ :?uid=/.test(attrs)) { return full }
+        if (UID_RE.test(attrs)) { return full }
         return `<${name} :uid="'${hash(relativeID)}' + JSON.stringify($props) + '${count}'"  ${attrs ?? ''}>`
       })
 

packages/nuxt/src/components/plugins/component-names.ts

@@ -7,6 +7,8 @@ interface NameDevPluginOptions {
   sourcemap: boolean
   getComponents: () => Component[]
 }
+const NOT_SX_RE = /\.[tj]sx$/
+const FILENAME_RE = /([^/\\]+)\.\w+$/
 /**
  * Set the default name of components to their PascalCase name
  */
@@ -15,10 +17,10 @@ export const ComponentNamePlugin = (options: NameDevPluginOptions) => createUnpl
     name: 'nuxt:component-name-plugin',
     enforce: 'post',
     transformInclude (id) {
-      return isVue(id) || !!id.match(/\.[tj]sx$/)
+      return isVue(id) || !!id.match(NOT_SX_RE)
     },
     transform (code, id) {
-      const filename = id.match(/([^/\\]+)\.\w+$/)?.[1]
+      const filename = id.match(FILENAME_RE)?.[1]
       if (!filename) {
         return
       }

packages/nuxt/src/components/plugins/islands-transform.ts

@@ -30,6 +30,7 @@ const TEMPLATE_RE = /<template>([\s\S]*)<\/template>/
 const NUXTCLIENT_ATTR_RE = /\s:?nuxt-client(="[^"]*")?/g
 const IMPORT_CODE = '\nimport { mergeProps as __mergeProps } from \'vue\'' + '\nimport { vforToArray as __vforToArray } from \'#app/components/utils\'' + '\nimport NuxtTeleportIslandComponent from \'#app/components/nuxt-teleport-island-component\'' + '\nimport NuxtTeleportSsrSlot from \'#app/components/nuxt-teleport-island-slot\''
 const EXTRACTED_ATTRS_RE = /v-(?:if|else-if|else)(="[^"]*")?/g
+const KEY_RE = /:?key="[^"]"/g
 
 function wrapWithVForDiv (code: string, vfor: string): string {
   return `<div v-for="${vfor}" style="display: contents;">${code}</div>`
@@ -90,7 +91,7 @@ export const IslandsTransformPlugin = (options: ServerOnlyComponentTransformPlug
           if (children.length) {
             // pass slot fallback to NuxtTeleportSsrSlot fallback
             const attrString = attributeToString(attributes)
-            const slice = code.slice(startingIndex + loc[0].end, startingIndex + loc[1].start).replaceAll(/:?key="[^"]"/g, '')
+            const slice = code.slice(startingIndex + loc[0].end, startingIndex + loc[1].start).replaceAll(KEY_RE, '')
             s.overwrite(startingIndex + loc[0].start, startingIndex + loc[1].end, `<slot${attrString.replaceAll(EXTRACTED_ATTRS_RE, '')}/><template #fallback>${attributes['v-for'] ? wrapWithVForDiv(slice, attributes['v-for']) : slice}</template>`)
           } else {
             s.overwrite(startingIndex + loc[0].start, startingIndex + loc[0].end, code.slice(startingIndex + loc[0].start, startingIndex + loc[0].end).replaceAll(EXTRACTED_ATTRS_RE, ''))

packages/nuxt/src/components/plugins/loader.ts

@@ -17,6 +17,8 @@ interface LoaderOptions {
   experimentalComponentIslands?: boolean
 }
 
+const REPLACE_COMPONENT_TO_DIRECT_IMPORT_RE = /(?<=[ (])_?resolveComponent\(\s*["'](lazy-|Lazy(?=[A-Z]))?([^'"]*)["'][^)]*\)/g
+const NOT_SX_RE = /\.[tj]sx$/
 export const LoaderPlugin = (options: LoaderOptions) => createUnplugin(() => {
   const exclude = options.transform?.exclude || []
   const include = options.transform?.include || []
@@ -32,7 +34,7 @@ export const LoaderPlugin = (options: LoaderOptions) => createUnplugin(() => {
       if (include.some(pattern => pattern.test(id))) {
         return true
       }
-      return isVue(id, { type: ['template', 'script'] }) || !!id.match(/\.[tj]sx$/)
+      return isVue(id, { type: ['template', 'script'] }) || !!id.match(IS_VUE_RE)
     },
     transform (code, id) {
       const components = options.getComponents()
@@ -43,7 +45,7 @@ export const LoaderPlugin = (options: LoaderOptions) => createUnplugin(() => {
       const s = new MagicString(code)
 
       // replace `_resolveComponent("...")` to direct import
-      s.replace(/(?<=[ (])_?resolveComponent\(\s*["'](lazy-|Lazy(?=[A-Z]))?([^'"]*)["'][^)]*\)/g, (full: string, lazy: string, name: string) => {
+      s.replace(REPLACE_COMPONENT_TO_DIRECT_IMPORT_RE, (full: string, lazy: string, name: string) => {
         const component = findComponent(components, name, options.mode)
         if (component) {
           // TODO: refactor to nuxi
@@ -110,8 +112,9 @@ export const LoaderPlugin = (options: LoaderOptions) => createUnplugin(() => {
   }
 })
 
+const QUOTE_RE = /["']/g
 function findComponent (components: Component[], name: string, mode: LoaderOptions['mode']) {
-  const id = pascalCase(name).replace(/["']/g, '')
+  const id = pascalCase(name).replace(QUOTE_RE, '')
   // Prefer exact match
   const component = components.find(component => id === component.pascalName && ['all', mode, undefined].includes(component.mode))
   if (component) { return component }

packages/nuxt/src/components/scan.ts

@@ -8,6 +8,11 @@ import type { Component, ComponentsDir } from 'nuxt/schema'
 
 import { resolveComponentNameSegments } from '../core/utils'
 
+const ISLAND_RE = /\.island(?:\.global)?$/
+const GLOBAL_RE = /\.global(?:\.island)?$/
+const COMPONENT_MODE_RE = /(?<=\.)(client|server)(\.global|\.island)*$/
+const MODE_REPLACEMENT_RE = /(\.(client|server))?(\.global|\.island)*$/
+const QUOTE_RE = /["']/g
 /**
  * Scan the components inside different components folders
  * and return a unique list of components
@@ -83,17 +88,17 @@ export async function scanComponents (dirs: ComponentsDir[], srcDir: string): Pr
        */
       let fileName = basename(filePath, extname(filePath))
 
-      const island = /\.island(?:\.global)?$/.test(fileName) || dir.island
+      const island = ISLAND_RE.test(fileName) || dir.island
-      const global = /\.global(?:\.island)?$/.test(fileName) || dir.global
+      const global = GLOBAL_RE.test(fileName) || dir.global
-      const mode = island ? 'server' : (fileName.match(/(?<=\.)(client|server)(\.global|\.island)*$/)?.[1] || 'all') as 'client' | 'server' | 'all'
+      const mode = island ? 'server' : (fileName.match(COMPONENT_MODE_RE)?.[1] || 'all') as 'client' | 'server' | 'all'
-      fileName = fileName.replace(/(\.(client|server))?(\.global|\.island)*$/, '')
+      fileName = fileName.replace(MODE_REPLACEMENT_RE, '')
 
       if (fileName.toLowerCase() === 'index') {
         fileName = dir.pathPrefix === false ? basename(dirname(filePath)) : '' /* inherits from path */
       }
 
       const suffix = (mode !== 'all' ? `-${mode}` : '')
-      const componentNameSegments = resolveComponentNameSegments(fileName.replace(/["']/g, ''), prefixParts)
+      const componentNameSegments = resolveComponentNameSegments(fileName.replace(QUOTE_RE, ''), prefixParts)
       const pascalName = pascalCase(componentNameSegments)
 
       if (LAZY_COMPONENT_NAME_REGEX.test(pascalName)) {

packages/nuxt/src/components/templates.ts

@@ -102,14 +102,15 @@ export const componentsIslandsTemplate: NuxtTemplate = {
   },
 }
 
+const NON_VUE_RE = /\b\.(?!vue)\w+$/g
 export const componentsTypeTemplate = {
   filename: 'components.d.ts' as const,
   getContents: ({ app, nuxt }) => {
     const buildDir = nuxt.options.buildDir
     const componentTypes = app.components.filter(c => !c.island).map((c) => {
       const type = `typeof ${genDynamicImport(isAbsolute(c.filePath)
-        ? relative(buildDir, c.filePath).replace(/\b\.(?!vue)\w+$/g, '')
+        ? relative(buildDir, c.filePath).replace(NON_VUE_RE, '')
-        : c.filePath.replace(/\b\.(?!vue)\w+$/g, ''), { wrapper: false })}['${c.export}']`
+        : c.filePath.replace(NON_VUE_RE, ''), { wrapper: false })}['${c.export}']`
       return [
         c.pascalName,
         c.island || c.mode === 'server' ? `IslandComponent<${type}>` : type,

packages/nuxt/src/core/app.ts

@@ -57,7 +57,7 @@ export async function generateApp (nuxt: Nuxt, app: NuxtApp, options: { filter?:
 
   const writes: Array<() => void> = []
   const changedTemplates: Array<ResolvedNuxtTemplate<any>> = []
-
+  const FORWARD_SLASH_RE = /\//g
   async function processTemplate (template: ResolvedNuxtTemplate) {
     const fullPath = template.dst || resolve(nuxt.options.buildDir, template.filename!)
     const start = performance.now()
@@ -77,7 +77,7 @@ export async function generateApp (nuxt: Nuxt, app: NuxtApp, options: { filter?:
 
       // In case a non-normalized absolute path is called for on Windows
       if (process.platform === 'win32') {
-        nuxt.vfs[fullPath.replace(/\//g, '\\')] = contents
+        nuxt.vfs[fullPath.replace(FORWARD_SLASH_RE, '\\')] = contents
       }
 
       changedTemplates.push(template)

packages/nuxt/src/core/builder.ts

@@ -10,6 +10,7 @@ import { generateApp as _generateApp, createApp } from './app'
 import { checkForExternalConfigurationFiles } from './external-config-files'
 import { cleanupCaches, getVueHash } from './cache'
 
+const IS_RESTART_PATH_RE = /^(?:app\.|error\.|plugins\/|middleware\/|layouts\/)/i
 export async function build (nuxt: Nuxt) {
   const app = createApp(nuxt)
   nuxt.apps.default = app
@@ -23,7 +24,7 @@ export async function build (nuxt: Nuxt) {
       if (event === 'change') { return }
       const path = resolve(nuxt.options.srcDir, relativePath)
       const relativePaths = nuxt.options._layers.map(l => relative(l.config.srcDir || l.cwd, path))
-      const restartPath = relativePaths.find(relativePath => /^(?:app\.|error\.|plugins\/|middleware\/|layouts\/)/i.test(relativePath))
+      const restartPath = relativePaths.find(relativePath => IS_RESTART_PATH_RE.test(relativePath))
       if (restartPath) {
         if (restartPath.startsWith('app')) {
           app.mainComponent = undefined

packages/nuxt/src/core/nitro.ts

@@ -25,12 +25,14 @@ const logLevelMapReverse = {
   verbose: 3,
 } satisfies Record<NuxtOptions['logLevel'], NitroConfig['logLevel']>
 
+const NODE_MODULES_RE = /(?<=\/)node_modules\/(.+)$/
+const PNPM_NODE_MODULES_RE = /\.pnpm\/.+\/node_modules\/(.+)$/
 export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
   // Resolve config
   const excludePaths = nuxt.options._layers
     .flatMap(l => [
-      l.cwd.match(/(?<=\/)node_modules\/(.+)$/)?.[1],
+      l.cwd.match(NODE_MODULES_RE)?.[1],
-      l.cwd.match(/\.pnpm\/.+\/node_modules\/(.+)$/)?.[1],
+      l.cwd.match(PNPM_NODE_MODULES_RE)?.[1],
     ])
     .filter((dir): dir is string => Boolean(dir))
     .map(dir => escapeRE(dir))
@@ -339,11 +341,12 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
   }
 
   // Add fallback server for `ssr: false`
+  const FORWARD_SLASH_RE = /\//g
   if (!nuxt.options.ssr) {
     nitroConfig.virtual!['#build/dist/server/server.mjs'] = 'export default () => {}'
     // In case a non-normalized absolute path is called for on Windows
     if (process.platform === 'win32') {
-      nitroConfig.virtual!['#build/dist/server/server.mjs'.replace(/\//g, '\\')] = 'export default () => {}'
+      nitroConfig.virtual!['#build/dist/server/server.mjs'.replace(FORWARD_SLASH_RE, '\\')] = 'export default () => {}'
     }
   }
 
@@ -351,7 +354,7 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
     nitroConfig.virtual!['#build/dist/server/styles.mjs'] = 'export default {}'
     // In case a non-normalized absolute path is called for on Windows
     if (process.platform === 'win32') {
-      nitroConfig.virtual!['#build/dist/server/styles.mjs'.replace(/\//g, '\\')] = 'export default {}'
+      nitroConfig.virtual!['#build/dist/server/styles.mjs'.replace(FORWARD_SLASH_RE, '\\')] = 'export default {}'
     }
   }
 
@@ -371,6 +374,7 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
 
   // TODO: extract to shared utility?
   const excludedAlias = [/^@vue\/.*$/, '#imports', 'vue-demi', /^#app/]
+  const EXTENSION_RE = /\b\.\w+$/g
   const basePath = nitroConfig.typescript!.tsConfig!.compilerOptions?.baseUrl ? resolve(nuxt.options.buildDir, nitroConfig.typescript!.tsConfig!.compilerOptions?.baseUrl) : nuxt.options.buildDir
   const aliases = nitroConfig.alias!
   const tsConfig = nitroConfig.typescript!.tsConfig!
@@ -389,7 +393,7 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
       tsConfig.compilerOptions.paths[alias] = [absolutePath]
       tsConfig.compilerOptions.paths[`${alias}/*`] = [`${absolutePath}/*`]
     } else {
-      tsConfig.compilerOptions.paths[alias] = [absolutePath.replace(/\b\.\w+$/g, '')] /* remove extension */
+      tsConfig.compilerOptions.paths[alias] = [absolutePath.replace(EXTENSION_RE, '')] /* remove extension */
     }
   }
 
@@ -566,8 +570,9 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
   }
 }
 
+const RELATIVE_RE = /^([^.])/
 function relativeWithDot (from: string, to: string) {
-  return relative(from, to).replace(/^([^.])/, './$1') || '.'
+  return relative(from, to).replace(RELATIVE_RE, './$1') || '.'
 }
 
 async function spaLoadingTemplatePath (nuxt: Nuxt) {

packages/nuxt/src/core/nuxt.ts

@@ -178,9 +178,10 @@ async function initNuxt (nuxt: Nuxt) {
 
   const coreTypePackages = nuxt.options.typescript.hoist || []
   const packageJSON = await readPackageJSON(nuxt.options.rootDir).catch(() => ({}) as PackageJson)
+  const NESTED_PKG_RE = /^[^@]+\//
   nuxt._dependencies = new Set([...Object.keys(packageJSON.dependencies || {}), ...Object.keys(packageJSON.devDependencies || {})])
   const paths = Object.fromEntries(await Promise.all(coreTypePackages.map(async (pkg) => {
-    const [_pkg = pkg, _subpath] = /^[^@]+\//.test(pkg) ? pkg.split('/') : [pkg]
+    const [_pkg = pkg, _subpath] = NESTED_PKG_RE.test(pkg) ? pkg.split('/') : [pkg]
     const subpath = _subpath ? '/' + _subpath : ''
 
     // ignore packages that exist in `package.json` as these can be resolved by TypeScript

packages/nuxt/src/core/plugins/virtual.ts

@@ -10,6 +10,7 @@ interface VirtualFSPluginOptions {
   alias?: Record<string, string>
 }
 
+const RELATIVE_ID_RE = /^\.{1,2}[\\/]/
 export const VirtualFSPlugin = (nuxt: Nuxt, options: VirtualFSPluginOptions) => createUnplugin(() => {
   const extensions = ['', ...nuxt.options.extensions]
   const alias = { ...nuxt.options.alias, ...options.alias }
@@ -40,7 +41,7 @@ export const VirtualFSPlugin = (nuxt: Nuxt, options: VirtualFSPluginOptions) =>
         return PREFIX + resolvedId
       }
 
-      if (importer && /^\.{1,2}[\\/]/.test(id)) {
+      if (importer && RELATIVE_ID_RE.test(id)) {
         const path = resolve(dirname(withoutPrefix(importer)), id)
         const resolved = resolveWithExt(path)
         if (resolved) {

packages/nuxt/src/core/templates.ts

@@ -57,6 +57,7 @@ export const cssTemplate: NuxtTemplate = {
   getContents: ctx => ctx.nuxt.options.css.map(i => genImport(i)).join('\n'),
 }
 
+const PLUGIN_TEMPLATE_RE = /_(45|46|47)/g
 export const clientPluginTemplate: NuxtTemplate = {
   filename: 'plugins.client.mjs',
   async getContents (ctx) {
@@ -66,7 +67,7 @@ export const clientPluginTemplate: NuxtTemplate = {
     const imports: string[] = []
     for (const plugin of clientPlugins) {
       const path = relative(ctx.nuxt.options.rootDir, plugin.src)
-      const variable = genSafeVariableName(filename(plugin.src)).replace(/_(45|46|47)/g, '_') + '_' + hash(path)
+      const variable = genSafeVariableName(filename(plugin.src)).replace(PLUGIN_TEMPLATE_RE, '_') + '_' + hash(path)
       exports.push(variable)
       imports.push(genImport(plugin.src, variable))
     }
@@ -86,7 +87,7 @@ export const serverPluginTemplate: NuxtTemplate = {
     const imports: string[] = []
     for (const plugin of serverPlugins) {
       const path = relative(ctx.nuxt.options.rootDir, plugin.src)
-      const variable = genSafeVariableName(filename(path)).replace(/_(45|46|47)/g, '_') + '_' + hash(path)
+      const variable = genSafeVariableName(filename(path)).replace(PLUGIN_TEMPLATE_RE, '_') + '_' + hash(path)
       exports.push(variable)
       imports.push(genImport(plugin.src, variable))
     }
@@ -98,7 +99,9 @@ export const serverPluginTemplate: NuxtTemplate = {
 }
 
 const TS_RE = /\.[cm]?tsx?$/
-
+const JS_LETTER_RE = /\.(?<letter>[cm])?jsx?$/
+const JS_RE = /\.[cm]jsx?$/
+const JS_CAPTURE_RE = /\.[cm](jsx?)$/
 export const pluginsDeclaration: NuxtTemplate = {
   filename: 'types/plugins.d.ts',
   getContents: async ({ nuxt, app }) => {
@@ -120,18 +123,18 @@ export const pluginsDeclaration: NuxtTemplate = {
       const pluginPath = resolve(typesDir, plugin.src)
       const relativePath = relative(typesDir, pluginPath)
 
-      const correspondingDeclaration = pluginPath.replace(/\.(?<letter>[cm])?jsx?$/, '.d.$<letter>ts')
+      const correspondingDeclaration = pluginPath.replace(JS_LETTER_RE, '.d.$<letter>ts')
       // if `.d.ts` file exists alongside a `.js` plugin, or if `.d.mts` file exists alongside a `.mjs` plugin, we can use the entire path
       if (correspondingDeclaration !== pluginPath && exists(correspondingDeclaration)) {
         tsImports.push(relativePath)
         continue
       }
 
-      const incorrectDeclaration = pluginPath.replace(/\.[cm]jsx?$/, '.d.ts')
+      const incorrectDeclaration = pluginPath.replace(JS_RE, '.d.ts')
       // if `.d.ts` file exists, but plugin is `.mjs`, add `.js` extension to the import
       // to hotfix issue until ecosystem updates to `@nuxt/module-builder@>=0.8.0`
       if (incorrectDeclaration !== pluginPath && exists(incorrectDeclaration)) {
-        tsImports.push(relativePath.replace(/\.[cm](jsx?)$/, '.$1'))
+        tsImports.push(relativePath.replace(JS_CAPTURE_RE, '.$1'))
         continue
       }
 
@@ -174,11 +177,13 @@ export { }
 }
 
 const adHocModules = ['router', 'pages', 'imports', 'meta', 'components', 'nuxt-config-schema']
+const IMPORT_NAME_RE = /\.\w+$/
+const GIT_RE = /^git\+/
 export const schemaTemplate: NuxtTemplate = {
   filename: 'types/schema.d.ts',
   getContents: async ({ nuxt }) => {
     const relativeRoot = relative(resolve(nuxt.options.buildDir, 'types'), nuxt.options.rootDir)
-    const getImportName = (name: string) => (name[0] === '.' ? './' + join(relativeRoot, name) : name).replace(/\.\w+$/, '')
+    const getImportName = (name: string) => (name[0] === '.' ? './' + join(relativeRoot, name) : name).replace(IMPORT_NAME_RE, '')
 
     const modules = nuxt.options._installedModules
       .filter(m => m.meta && m.meta.configKey && m.meta.name && !adHocModules.includes(m.meta.name))
@@ -210,7 +215,7 @@ export const schemaTemplate: NuxtTemplate = {
           }
           if (link) {
             if (link.startsWith('git+')) {
-              link = link.replace(/^git\+/, '')
+              link = link.replace(GIT_RE, '')
             }
             if (!link.startsWith('http')) {
               link = 'https://github.com/' + link
@@ -373,11 +378,12 @@ export const clientConfigTemplate: NuxtTemplate = {
   },
 }
 
+const FILENAME_EXTENSION_RE = /\b\.\w+$/g
 export const appConfigDeclarationTemplate: NuxtTemplate = {
   filename: 'types/app.config.d.ts',
   getContents ({ app, nuxt }) {
     const typesDir = join(nuxt.options.buildDir, 'types')
-    const configPaths = app.configs.map(path => relative(typesDir, path).replace(/\b\.\w+$/g, ''))
+    const configPaths = app.configs.map(path => relative(typesDir, path).replace(FILENAME_EXTENSION_RE, ''))
 
     return `
 import type { CustomAppConfig } from 'nuxt/schema'

packages/nuxt/src/core/utils/names.ts

@@ -2,6 +2,7 @@ import { basename, dirname, extname, normalize } from 'pathe'
 import { kebabCase, splitByCase } from 'scule'
 import { withTrailingSlash } from 'ufo'
 
+const QUOTE_RE = /["']/g
 export function getNameFromPath (path: string, relativeTo?: string) {
   const relativePath = relativeTo
     ? normalize(path).replace(withTrailingSlash(normalize(relativeTo)), '')
@@ -9,7 +10,7 @@ export function getNameFromPath (path: string, relativeTo?: string) {
   const prefixParts = splitByCase(dirname(relativePath))
   const fileName = basename(relativePath, extname(relativePath))
   const segments = resolveComponentNameSegments(fileName.toLowerCase() === 'index' ? '' : fileName, prefixParts).filter(Boolean)
-  return kebabCase(segments).replace(/["']/g, '')
+  return kebabCase(segments).replace(QUOTE_RE, '')
 }
 
 export function hasSuffix (path: string, suffix: string) {

packages/nuxt/src/pages/plugins/page-meta.ts

@@ -176,8 +176,9 @@ export const PageMetaPlugin = (options: PageMetaPluginOptions) => createUnplugin
 
 // https://github.com/vuejs/vue-loader/pull/1911
 // https://github.com/vitejs/vite/issues/8473
+const QUERY_START_RE = /^\?/
 function rewriteQuery (id: string) {
-  return id.replace(/\?.+$/, r => '?macro=true&' + r.replace(/^\?/, '').replace(/&macro=true/, ''))
+  return id.replace(/\?.+$/, r => '?macro=true&' + r.replace(QUERY_START_RE, '').replace(/&macro=true/, ''))
 }
 
 function parseMacroQuery (id: string) {
@@ -189,6 +190,7 @@ function parseMacroQuery (id: string) {
   return query
 }
 
+const QUOTED_SPECIFIER_RE = /(["']).*\1/
 function getQuotedSpecifier (id: string) {
-  return id.match(/(["']).*\1/)?.[0]
+  return id.match(QUOTED_SPECIFIER_RE)?.[0]
 }

packages/nuxt/src/pages/runtime/utils.ts

@@ -5,11 +5,14 @@ type InstanceOf<T> = T extends new (...args: any[]) => infer R ? R : never
 type RouterViewSlot = Exclude<InstanceOf<typeof RouterView>['$slots']['default'], undefined>
 export type RouterViewSlotProps = Parameters<RouterViewSlot>[0]
 
+const ROUTE_KEY_PARENTHESES_RE = /(:\w+)\([^)]+\)/g
+const ROUTE_KEY_SYMBOLS_RE = /(:\w+)[?+*]/g
+const ROUTE_KEY_NORMAL_RE = /:\w+/g
 const interpolatePath = (route: RouteLocationNormalizedLoaded, match: RouteLocationMatched) => {
   return match.path
-    .replace(/(:\w+)\([^)]+\)/g, '$1')
+    .replace(ROUTE_KEY_PARENTHESES_RE, '$1')
-    .replace(/(:\w+)[?+*]/g, '$1')
+    .replace(ROUTE_KEY_SYMBOLS_RE, '$1')
-    .replace(/:\w+/g, r => route.params[r.slice(1)]?.toString() || '')
+    .replace(ROUTE_KEY_NORMAL_RE, r => route.params[r.slice(1)]?.toString() || '')
 }
 
 export const generateRouteKey = (routeProps: RouterViewSlotProps, override?: string | ((route: RouteLocationNormalizedLoaded) => string)) => {

packages/nuxt/src/pages/utils.ts

@@ -83,6 +83,7 @@ type GenerateRoutesFromFilesOptions = {
   shouldUseServerComponents?: boolean
 }
 
+const INDEX_PAGE_RE = /\/index$/
 export function generateRoutesFromFiles (files: ScannedFile[], options: GenerateRoutesFromFilesOptions = {}): NuxtPage[] {
   const routes: NuxtPage[] = []
 
@@ -128,7 +129,7 @@ export function generateRoutesFromFiles (files: ScannedFile[], options: Generate
       route.name += (route.name && '/') + segmentName
 
       // ex: parent.vue + parent/child.vue
-      const path = withLeadingSlash(joinURL(route.path, getRoutePath(tokens).replace(/\/index$/, '/')))
+      const path = withLeadingSlash(joinURL(route.path, getRoutePath(tokens).replace(INDEX_PAGE_RE, '/')))
       const child = parent.find(parentRoute => parentRoute.name === route.name && parentRoute.path === path)
 
       if (child && child.children) {
@@ -300,6 +301,7 @@ export async function getRouteMeta (contents: string, absolutePath: string): Pro
   return extractedMeta
 }
 
+const COLON_RE = /:/g
 function getRoutePath (tokens: SegmentToken[]): string {
   return tokens.reduce((path, token) => {
     return (
@@ -312,7 +314,7 @@ function getRoutePath (tokens: SegmentToken[]): string {
             ? `:${token.value}(.*)*`
             : token.type === SegmentTokenType.group
               ? ''
-              : encodePath(token.value).replace(/:/g, '\\:'))
+              : encodePath(token.value).replace(COLON_RE, '\\:'))
     )
   }, '/')
 }
@@ -432,13 +434,14 @@ function findRouteByName (name: string, routes: NuxtPage[]): NuxtPage | undefine
   return findRouteByName(name, routes)
 }
 
+const NESTED_PAGE_RE = /\//g
 function prepareRoutes (routes: NuxtPage[], parent?: NuxtPage, names = new Set<string>()) {
   for (const route of routes) {
     // Remove -index
     if (route.name) {
       route.name = route.name
-        .replace(/\/index$/, '')
+        .replace(INDEX_PAGE_RE, '')
-        .replace(/\//g, '-')
+        .replace(NESTED_PAGE_RE, '-')
 
       if (names.has(route.name)) {
         const existingRoute = findRouteByName(route.name, routes)
@@ -600,6 +603,7 @@ async function createClientPage(loader) {
   }
 }
 
+const PATH_TO_NITRO_GLOB_RE = /\/[^:/]*:\w.*$/
 export function pathToNitroGlob (path: string) {
   if (!path) {
     return null
@@ -609,7 +613,7 @@ export function pathToNitroGlob (path: string) {
     return null
   }
 
-  return path.replace(/\/[^:/]*:\w.*$/, '/**')
+  return path.replace(PATH_TO_NITRO_GLOB_RE, '/**')
 }
 
 export function resolveRoutePaths (page: NuxtPage, parent = '/'): string[] {

packages/vite/src/plugins/composable-keys.ts

@@ -20,6 +20,7 @@ interface ComposableKeysOptions {
 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)/
+const SCRIPT_RE = /(?<=<script[^>]*>)[\s\S]*?(?=<\/script>)/i
 
 export const composableKeysPlugin = createUnplugin((options: ComposableKeysOptions) => {
   const composableMeta: Record<string, any> = {}
@@ -43,7 +44,7 @@ export const composableKeysPlugin = createUnplugin((options: ComposableKeysOptio
     },
     transform (code, id) {
       if (!KEYED_FUNCTIONS_RE.test(code)) { return }
-      const { 0: script = code, index: codeIndex = 0 } = code.match(/(?<=<script[^>]*>)[\s\S]*?(?=<\/script>)/i) || { index: 0, 0: code }
+      const { 0: script = code, index: codeIndex = 0 } = code.match(SCRIPT_RE) || { index: 0, 0: code }
       const s = new MagicString(code)
       // https://github.com/unjs/unplugin/issues/90
       let imports: Set<string> | undefined

packages/vite/src/plugins/public-dirs.ts

@@ -10,6 +10,7 @@ import { isCSSRequest } from 'vite'
 const PREFIX = 'virtual:public?'
 const CSS_URL_RE = /url\((\/[^)]+)\)/g
 const CSS_URL_SINGLE_RE = /url\(\/[^)]+\)/
+const RENDER_CHUNK_RE = /(?<= = )['"`]/
 
 interface VitePublicDirsPluginOptions {
   dev?: boolean
@@ -70,7 +71,7 @@ export const VitePublicDirsPlugin = createUnplugin((options: VitePublicDirsPlugi
           if (!chunk.facadeModuleId?.includes('?inline&used')) { return }
 
           const s = new MagicString(code)
-          const q = code.match(/(?<= = )['"`]/)?.[0] || '"'
+          const q = code.match(RENDER_CHUNK_RE)?.[0] || '"'
           for (const [full, url] of code.matchAll(CSS_URL_RE)) {
             if (url && resolveFromPublicAssets(url)) {
               s.replace(full, `url(${q} + publicAssetsURL(${q}${url}${q}) + ${q})`)
@@ -108,13 +109,14 @@ export const VitePublicDirsPlugin = createUnplugin((options: VitePublicDirsPlugi
   ]
 })
 
+const PUBLIC_ASSETS_RE = /[?#].*$/
 export function useResolveFromPublicAssets () {
   const nitro = useNitro()
 
   function resolveFromPublicAssets (id: string) {
     for (const dir of nitro.options.publicAssets) {
       if (!id.startsWith(withTrailingSlash(dir.baseURL || '/'))) { continue }
-      const path = id.replace(/[?#].*$/, '').replace(withTrailingSlash(dir.baseURL || '/'), withTrailingSlash(dir.dir))
+      const path = id.replace(PUBLIC_ASSETS_RE, '').replace(withTrailingSlash(dir.baseURL || '/'), withTrailingSlash(dir.dir))
       if (existsSync(path)) {
         return id
       }

packages/vite/src/utils/logger.ts

@@ -23,6 +23,7 @@ const logLevelMapReverse: Record<NonNullable<vite.UserConfig['logLevel']>, numbe
   info: 3,
 }
 
+const RUNTIME_RESOLVE_REF_RE = /^([^ ]+) referenced in/m
 export function createViteLogger (config: vite.InlineConfig): vite.Logger {
   const loggedErrors = new WeakSet<any>()
   const canClearScreen = hasTTY && !isCI && config.clearScreen
@@ -37,7 +38,7 @@ export function createViteLogger (config: vite.InlineConfig): vite.Logger {
       if (msg.startsWith('Sourcemap') && msg.includes('node_modules')) { return }
       // Hide warnings about externals produced by https://github.com/vitejs/vite/blob/v5.2.11/packages/vite/src/node/plugins/css.ts#L350-L355
       if (msg.includes('didn\'t resolve at build time, it will remain unchanged to be resolved at runtime')) {
-        const id = msg.trim().match(/^([^ ]+) referenced in/m)?.[1]
+        const id = msg.trim().match(RUNTIME_RESOLVE_REF_RE)?.[1]
         if (id && resolveFromPublicAssets(id)) { return }
       }
     }

packages/webpack/src/nitro/plugins/dynamic-require.ts

@@ -7,6 +7,7 @@ import { importModule } from '@nuxt/kit'
 const PLUGIN_NAME = 'dynamic-require'
 const HELPER_DYNAMIC = `\0${PLUGIN_NAME}.mjs`
 const DYNAMIC_REQUIRE_RE = /import\("\.\/" ?\+(.*)\).then/g
+const BACKWARD_SLASH_RE = /\\/g
 
 interface Options {
   dir: string
@@ -75,7 +76,7 @@ export function dynamicRequire ({ dir, ignore, inline }: Options): Plugin {
         await Promise.all(
           files.map(async id => ({
             id,
-            src: resolve(dir, id).replace(/\\/g, '/'),
+            src: resolve(dir, id).replace(BACKWARD_SLASH_RE, '/'),
             name: genSafeVariableName(id),
             meta: await getWebpackChunkMeta(resolve(dir, id)),
           })),

packages/webpack/src/plugins/vue/util.ts

@@ -24,6 +24,8 @@ export const isJS = (file: string) => isJSRegExp.test(file)
 
 export const extractQueryPartJS = (file: string) => isJSRegExp.exec(file)?.[1]
 
-export const isCSS = (file: string) => /\.css(?:\?[^.]+)?$/.test(file)
+const isCSSRegExp = /\.css(?:\?[^.]+)?$/
+
+export const isCSS = (file: string) => isCSSRegExp.test(file)
 
 export const isHotUpdate = (file: string) => file.includes('hot-update')