feat(dynamic-links, ios): performDiagnostics API for troubleshooting

docs/dynamic-links/usage/index.md

@@ -135,6 +135,8 @@ The iOS Notes app is a good place to paste your dynamic link and test it opens y
 
 6. Make sure your [deep link parameter](https://firebase.google.com/docs/dynamic-links/create-manually?authuser=0#parameters) is properly URL-encoded, especially if it contains a query string.
 
+7. Try the `performDiagnostics` API on the Dynamic Links module, while running the app on a real device and watching output from either Xcode or Console app. You may search for "Links" and you will see the diagnostic output.
+
 ## Android Setup
 
 1. Create a SHA-256 fingerprint using these [instructions](https://developers.google.com/android/guides/client-auth) for your app, and add to your app in your Firebase console.

packages/dynamic-links/e2e/dynamicLinks.e2e.js

@@ -237,4 +237,10 @@ describe('dynamicLinks()', function () {
       }
     });
   });
+
+  describe('performDiagnostics()', function () {
+    it('should perform diagnostics without error', async function () {
+      firebase.dynamicLinks().performDiagnostics();
+    });
+  });
 });

packages/dynamic-links/ios/RNFBDynamicLinks/RNFBDynamicLinksModule.m

@@ -228,6 +228,8 @@ - (id)init {
   }
 }
 
+RCT_EXPORT_METHOD(performDiagnostics) { [FIRDynamicLinks performDiagnosticsWithCompletion:nil]; }
+
 RCT_EXPORT_METHOD(resolveLink
                   : (NSString *)link
                   : (RCTPromiseResolveBlock)resolve

packages/dynamic-links/lib/index.d.ts

@@ -549,6 +549,15 @@ export namespace FirebaseDynamicLinksTypes {
      */
     onLink(listener: (link: DynamicLink) => void): () => void;
 
+    /**
+     * Perform built-in diagnostics on iOS. This is best performed on a real device running
+     * a build from Xcode so you may see the output easily. Alternatively it should be visible
+     * in Console.app with an iPhone plugged into a macOS computer
+     *
+     * NOTE: iOS only
+     */
+    performDiagnostics(): void;
+
     /**
      * Resolve a given dynamic link (short or long) directly.
      *

packages/dynamic-links/lib/index.js

@@ -20,6 +20,7 @@ import {
   FirebaseModule,
   getFirebaseRoot,
 } from '@react-native-firebase/app/lib/internal';
+import { isIOS } from '@react-native-firebase/app/lib/common';
 import builder from './builder';
 import version from './version';
 
@@ -86,6 +87,14 @@ class FirebaseLinksModule extends FirebaseModule {
     };
   }
 
+  performDiagnostics() {
+    if (isIOS) {
+      return this.native.performDiagnostics();
+    }
+
+    Promise.resolve();
+  }
+
   resolveLink(link) {
     if (!link) {
       throw new Error('firebase.dynamicLinks().resolve(*) Invalid link parameter');