Don't include # when url fragment is empty

Author: lisajian

packages/auth/src/core/util/handler.ts

@@ -120,11 +120,12 @@ export async function _getRedirectUrl(
   const appCheckTokenFragment = appCheckToken
     ? `${FIREBASE_APP_CHECK_FRAGMENT_ID}=${encodeURIComponent(appCheckToken)}`
     : '';
+  const fragment = appCheckTokenFragment ? `#${appCheckTokenFragment}` : '';
 
   // Start at index 1 to skip the leading '&' in the query string
   return `${getHandlerBase(auth)}?${querystring(paramsDict).slice(
     1
-  )}#${appCheckTokenFragment}`;
+  )}${fragment}`;
 }
 
 function getHandlerBase({ config }: AuthInternal): string {

packages/auth/src/platform_browser/popup_redirect.test.ts

@@ -150,9 +150,9 @@ describe('platform_browser/popup_redirect', () => {
       await resolver._openPopup(auth, provider, event);
 
       const matches = (popupUrl as string).match(/.*?#(.*)/);
-      expect(matches).not.to.be.null;
-      const fragment = matches![1];
-      expect(fragment).to.be.empty;
+      // The '#' character will not be included when the url fragment is not attached,
+      // so the url will not match the pattern
+      expect(matches).to.be.null;
     });
 
     it('does not add the App Check token in the url fragment if controller unavailable', async () => {
@@ -164,9 +164,9 @@ describe('platform_browser/popup_redirect', () => {
       await resolver._openPopup(auth, provider, event);
 
       const matches = (popupUrl as string).match(/.*?#(.*)/);
-      expect(matches).not.to.be.null;
-      const fragment = matches![1];
-      expect(fragment).to.be.empty;
+      // The '#' character will not be included when the url fragment is not attached,
+      // so the url will not match the pattern
+      expect(matches).to.be.null;
     });
 
     it('throws an error if apiKey is unspecified', async () => {
@@ -259,9 +259,9 @@ describe('platform_browser/popup_redirect', () => {
       });
 
       const matches = newWindowLocation.match(/.*?#(.*)/);
-      expect(matches).not.to.be.null;
-      const fragment = matches![1];
-      expect(fragment).to.be.empty;
+      // The '#' character will not be included when the url fragment is not attached,
+      // so the url will not match the pattern
+      expect(matches).to.be.null;
     });
 
     it('does not add the App Check token in the url fragment if controller unavailable', async () => {
@@ -279,9 +279,9 @@ describe('platform_browser/popup_redirect', () => {
       });
 
       const matches = newWindowLocation.match(/.*?#(.*)/);
-      expect(matches).not.to.be.null;
-      const fragment = matches![1];
-      expect(fragment).to.be.empty;
+      // The '#' character will not be included when the url fragment is not attached,
+      // so the url will not match the pattern
+      expect(matches).to.be.null;
     });
 
     it('throws an error if authDomain is unspecified', async () => {