Add console warning

Author: brophdawg11

packages/react-router/__tests__/resolvePath-test.tsx

@@ -66,12 +66,17 @@ describe("resolvePath", () => {
   });
 
   it("normalizes any mid-path double-slashes", () => {
+    let spy = jest.spyOn(console, "warn").mockImplementation(() => {});
+
     expect(resolvePath("/search/../..//foo")).toMatchObject({
       pathname: "/foo",
     });
+
     expect(resolvePath("search/../..//foo", "/inbox")).toMatchObject({
       pathname: "/foo",
     });
+
+    spy.mockRestore();
   });
 
   it('ignores trailing slashes on the "from" pathname when resolving relative paths', () => {

packages/react-router/lib/router/router.ts

@@ -58,6 +58,7 @@ import {
   convertRoutesToDataRoutes,
   getPathContributingMatches,
   getResolveToMatches,
+  isAbsoluteUrl,
   isUnsupportedLazyRouteObjectKey,
   isUnsupportedLazyRouteFunctionKey,
   isRouteErrorResponse,
@@ -838,9 +839,6 @@ export const IDLE_BLOCKER: BlockerUnblocked = {
   location: undefined,
 };
 
-const ABSOLUTE_URL_REGEX = /^(?:[a-z][a-z0-9+.-]*:|\/\/)/i;
-export const isAbsoluteUrl = (url: string) => ABSOLUTE_URL_REGEX.test(url);
-
 const defaultMapRouteProperties: MapRoutePropertiesFunction = (route) => ({
   hasErrorBoundary: Boolean(route.hasErrorBoundary),
 });

packages/react-router/lib/router/utils.ts

@@ -1571,6 +1571,9 @@ export function prependBasename({
   return pathname === "/" ? basename : joinPaths([basename, pathname]);
 }
 
+const ABSOLUTE_URL_REGEX = /^(?:[a-z][a-z0-9+.-]*:|\/\/)/i;
+export const isAbsoluteUrl = (url: string) => ABSOLUTE_URL_REGEX.test(url);
+
 /**
  * Returns a resolved {@link Path} object relative to the given pathname.
  *
@@ -1590,11 +1593,18 @@ export function resolvePath(to: To, fromPathname = "/"): Path {
 
   let pathname: string;
   if (toPathname) {
-    if (toPathname.startsWith("//")) {
+    if (isAbsoluteUrl(toPathname)) {
       pathname = toPathname;
     } else {
-      // Normalize double-slashes
-      toPathname = toPathname.replace(/\/\/+/g, "/");
+      if (toPathname.includes("//")) {
+        let oldPathname = toPathname;
+        toPathname = toPathname.replace(/\/\/+/g, "/");
+        warning(
+          false,
+          `Pathnames cannot have embedded double slashes - normalizing ` +
+            `${oldPathname} -> ${toPathname}`,
+        );
+      }
       if (toPathname.startsWith("/")) {
         pathname = resolvePathname(toPathname.substring(1), "/");
       } else {

packages/react-router/lib/rsc/server.rsc.ts

@@ -12,7 +12,6 @@ import type {
 import { type Location } from "../router/history";
 import {
   createStaticHandler,
-  isAbsoluteUrl,
   isMutationMethod,
   isResponse,
   isRedirectResponse,
@@ -26,6 +25,7 @@ import {
   type ShouldRevalidateFunction,
   type RouterContextProvider,
   type TrackedPromise,
+  isAbsoluteUrl,
   isRouteErrorResponse,
   matchRoutes,
   prependBasename,