Add check for unauthenticated error and sign out in fetchNewLatestRelease (#6648)

* Add check for unauthenticated error and sign out in fetchNewRelase method

* Update CHANGELOG

* Add check for Tester sign in before calling fetch

Author: schnecle

FirebaseAppDistribution/CHANGELOG.md

@@ -1,3 +1,6 @@
+# Unreleased
+- [changed] Sign out the Tester when the call to fetch releases fails with an unauthenticated error.
+
 # v0.9.3
 - [changed] Updated error log for non-200 API Service calls.
 

FirebaseAppDistribution/Sources/FIRAppDistribution.m

@@ -252,6 +252,12 @@ - (void)fetchNewLatestRelease:(void (^)(FIRAppDistributionRelease *_Nullable rel
   [FIRFADApiService
       fetchReleasesWithCompletion:^(NSArray *_Nullable releases, NSError *_Nullable error) {
         if (error) {
+          if ([error code] == FIRFADApiErrorUnauthenticated) {
+            FIRFADErrorLog(@"Tester authentication failed when fetching releases. Tester will need "
+                           @"to sign in again.");
+            [self signOutTester];
+          }
+
           dispatch_async(dispatch_get_main_queue(), ^{
             completion(nil, [self mapFetchReleasesError:error]);
           });

FirebaseAppDistribution/Tests/Unit/FIRAppDistributionTests.m

@@ -355,6 +355,33 @@ - (void)testFetchNewLatestReleaseFailure {
   OCMReject([_mockMachO codeHash]);
 }
 
+- (void)testFetchNewLatestReleaseUnauthenticatedFailure {
+  NSError *mockError =
+      [NSError errorWithDomain:kFIRFADApiErrorDomain
+                          code:FIRFADApiErrorUnauthenticated
+                      userInfo:@{NSLocalizedDescriptionKey : @"This is unfortunate."}];
+  [self mockFetchReleasesCompletion:nil error:mockError];
+  OCMStub([_mockMachO codeHash]).andReturn(@"this-is-old");
+  [[GULUserDefaults standardUserDefaults] setBool:YES forKey:@"FIRFADSignInState"];
+  XCTAssertTrue([[self appDistribution] isTesterSignedIn]);
+
+  XCTestExpectation *expectation = [self expectationWithDescription:@"Fetch latest release fails."];
+
+  [[self appDistribution] fetchNewLatestRelease:^(FIRAppDistributionRelease *_Nullable release,
+                                                  NSError *_Nullable error) {
+    XCTAssertNil(release);
+    XCTAssertNotNil(error);
+    XCTAssertEqual([error code], FIRAppDistributionErrorAuthenticationFailure);
+    XCTAssertEqual([error domain], FIRAppDistributionErrorDomain);
+    XCTAssertFalse([[self appDistribution] isTesterSignedIn]);
+    [expectation fulfill];
+  }];
+
+  [self waitForExpectations:@[ expectation ] timeout:5.0];
+  [self verifyFetchReleasesCompletion];
+  OCMReject([_mockMachO codeHash]);
+}
+
 - (void)testCheckForUpdateWithCompletionTesterSignedIn {
   [self mockInstallationIdCompletion:_mockInstallationId error:nil];
   [self mockUIServiceRegistrationCompletion:nil];