feat: expose getRouteRulesForPath from nitro runtime (#2238)

src/runtime/cache.ts

@@ -199,7 +199,7 @@ export interface CachedEventHandlerOptions<T = any>
   shouldBypassCache?: (event: H3Event) => boolean | Promise<boolean>;
   getKey?: (event: H3Event) => string | Promise<string>;
   headersOnly?: boolean;
-  varies?: string[];
+  varies?: string[] | readonly string[];
 }
 
 function escapeKey(key: string | string[]) {

src/runtime/index.ts

@@ -4,7 +4,7 @@ export { useNitroApp } from "./app";
 export * from "./plugin";
 export * from "./task";
 export * from "./renderer";
-export { getRouteRules } from "./route-rules";
+export { getRouteRules, getRouteRulesForPath } from "./route-rules";
 export { useStorage } from "./storage";
 export { useEvent } from "./context";
 export { defineNitroErrorHandler } from "./error";

src/runtime/route-rules.ts

@@ -74,6 +74,15 @@ export function getRouteRules(event: H3Event): NitroRouteRules {
   return event.context._nitro.routeRules;
 }
 
-export function getRouteRulesForPath(path: string): NitroRouteRules {
+type DeepReadonly<T> =
+  T extends Record<string, any>
+    ? { readonly [K in keyof T]: DeepReadonly<T[K]> }
+    : T extends Array<infer U>
+      ? ReadonlyArray<DeepReadonly<U>>
+      : T;
+
+export function getRouteRulesForPath(
+  path: string
+): DeepReadonly<NitroRouteRules> {
   return defu({}, ..._routeRulesMatcher.matchAll(path).reverse());
 }