fix(core): undefined providerId (#12947)

* Fix undefined providerId

Client-side auth with no `providerId` param results in error.

* dev: Add test for 'undefined' provider url-parsing.test.ts

* simplify tests

* formatting

---------

Co-authored-by: Thang Vu <[email protected]>

Author: Regloom

packages/core/src/lib/utils/web.ts

@@ -144,5 +144,8 @@ export function parseActionAndProviderId(
   )
     throw new UnknownAction(`Cannot parse action at ${pathname}`)
 
-  return { action, providerId }
+  return {
+    action,
+    providerId: providerId == "undefined" ? undefined : providerId,
+  }
 }

packages/core/test/url-parsing.test.ts

@@ -70,6 +70,12 @@ describe("parse the action and provider id", () => {
       providerId: "auth0",
       basePath: "/auth",
     },
+    {
+      path: "/auth/signin/undefined",
+      action: "signin",
+      providerId: undefined,
+      basePath: "/auth",
+    },
   ])("$path", ({ path, error, basePath, action, providerId }) => {
     if (action || providerId) {
       const parsed = parseActionAndProviderId(path, basePath)