Add sanity checks for passed in options and initializers to GIDVerifyAccountDetail.

GoogleSignIn/Sources/GIDVerifyAccountDetail/Implementations/GIDVerifyAccountDetail.m

@@ -27,6 +27,30 @@
 
 @implementation GIDVerifyAccountDetail
 
+- (instancetype)initWithConfig:(GIDConfiguration *)configuration {
+  self = [super init];
+  if (self) {
+    _configuration = configuration;
+  }
+  return self;
+}
+
+- (instancetype)init {
+  GIDConfiguration *configuration;
+  NSBundle *bundle = NSBundle.mainBundle;
+  if (bundle) {
+    configuration = [GIDConfiguration configurationFromBundle:bundle];
+  }
+
+  if (!configuration) {
+    return nil;
+  }
+
+  return [self initWithConfig:configuration];
+}
+
+#pragma mark - Public methods
+
 - (void)verifyAccountDetails:(NSArray<GIDVerifiableAccountDetail *> *)accountDetails
     presentingViewController:(UIViewController *)presentingViewController
                   completion:(nullable void (^)(GIDVerifiedAccountDetailResult *_Nullable verifyResult,
@@ -42,11 +66,6 @@ - (void)verifyAccountDetails:(NSArray<GIDVerifiableAccountDetail *> *)accountDet
                         hint:(nullable NSString *)hint
                   completion:(nullable void (^)(GIDVerifiedAccountDetailResult *_Nullable verifyResult,
                                                 NSError *_Nullable error))completion {
-  NSBundle *bundle = NSBundle.mainBundle;
-  if (bundle) {
-    _configuration = [GIDConfiguration configurationFromBundle:bundle];
-  }
-
   GIDSignInInternalOptions *options =
   [GIDSignInInternalOptions defaultOptionsWithConfiguration:_configuration
                                    presentingViewController:presentingViewController
@@ -58,8 +77,69 @@ - (void)verifyAccountDetails:(NSArray<GIDVerifiableAccountDetail *> *)accountDet
   [self verifyAccountDetailsInteractivelyWithOptions:options];
 }
 
+#pragma mark - Authentication flow
+
 - (void)verifyAccountDetailsInteractivelyWithOptions:(GIDSignInInternalOptions *)options {
-  // TODO(#397): Sanity checks and start the incremental authorization flow.
+  if (!options.interactive) {
+    return;
+  }
+
+  // Ensure that a configuration is set.
+  if (!_configuration) {
+    // NOLINTNEXTLINE(google-objc-avoid-throwing-exception)
+    [NSException raise:NSInvalidArgumentException
+                format:@"No active configuration. Make sure GIDClientID is set in Info.plist."];
+    return;
+  }
+
+  [self assertValidCurrentUser];
+
+  // Explicitly throw exception for missing client ID here. This must come before
+  // scheme check because schemes rely on reverse client IDs.
+  [self assertValidParameters:options];
+
+  [self assertValidPresentingViewController:options];
+
+  // If the application does not support the required URL schemes tell the developer so.
+  GIDSignInCallbackSchemes *schemes =
+  [[GIDSignInCallbackSchemes alloc] initWithClientIdentifier:options.configuration.clientID];
+  NSArray<NSString *> *unsupportedSchemes = [schemes unsupportedSchemes];
+  if (unsupportedSchemes.count != 0) {
+    // NOLINTNEXTLINE(google-objc-avoid-throwing-exception)
+    [NSException raise:NSInvalidArgumentException
+                format:@"Your app is missing support for the following URL schemes: %@",
+     [unsupportedSchemes componentsJoinedByString:@", "]];
+  }
+  // TODO(#397): Start the incremental authorization flow.
+}
+
+#pragma mark - Helpers
+
+// Assert that a current user exists.
+- (void)assertValidCurrentUser {
+  if (!GIDSignIn.sharedInstance.currentUser) {
+    // NOLINTNEXTLINE(google-objc-avoid-throwing-exception)
+    [NSException raise:NSInvalidArgumentException
+                format:@"|currentUser| must be set to verify."];
+  }
+}
+
+// Asserts the parameters being valid.
+- (void)assertValidParameters:(GIDSignInInternalOptions *)options {
+  if (![options.configuration.clientID length]) {
+    // NOLINTNEXTLINE(google-objc-avoid-throwing-exception)
+    [NSException raise:NSInvalidArgumentException
+                format:@"You must specify |clientID| in |GIDConfiguration|"];
+  }
+}
+
+// Assert that the presenting view controller has been set.
+- (void)assertValidPresentingViewController:(GIDSignInInternalOptions *)options {
+  if (!options.presentingViewController) {
+    // NOLINTNEXTLINE(google-objc-avoid-throwing-exception)
+    [NSException raise:NSInvalidArgumentException
+                format:@"|presentingViewController| must be set."];
+  }
 }
 
 @end

GoogleSignIn/Sources/Public/GoogleSignIn/GIDVerifyAccountDetail.h

@@ -43,6 +43,21 @@ typedef void (^GIDVerifyCompletion)(GIDVerifiedAccountDetailResult *_Nullable ve
 /// The active configuration for this instance of `GIDVerifyAccountDetail`.
 @property(nonatomic, nullable) GIDConfiguration *configuration;
 
+/// Initialize a `GIDVerifyAccountDetail` object by specifying all available properties.
+///
+/// @param config The configuration to be used.
+/// @return An initialized `GIDVerifyAccountDetail` instance.
+- (instancetype)initWithConfig:(GIDConfiguration *)config
+    NS_DESIGNATED_INITIALIZER;
+
+
+/// Initialize a `GIDVerifyAccountDetail` object by calling the designated initializer 
+/// with the default configuration from the bundle's Info.plist.
+///
+/// @return An initialized `GIDVerifyAccountDetail` instance.
+///     Otherwise, `nil` if the configuration cannot be automatically generated from your app's Info.plist.
+- (instancetype)init;
+
 /// Starts an interactive verification flow.
 ///
 /// The completion will be called at the end of this process.  Any saved verification

GoogleSignIn/Tests/Unit/GIDFakeMainBundle.h

@@ -16,18 +16,45 @@
 
 #import <Foundation/Foundation.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 /**
  * @class GIDFakeMainBundle
  * @brief Helps fake [NSBundle mainBundle]
  */
 @interface GIDFakeMainBundle : NSObject
 
+/**
+ * @fn initWithClientID:serverClientID:hostedDomain:openIDRealm:
+ * @brief Initializes a GIDFakeMainBundle object.
+ * @param clientID The fake client idenfitier for the app.
+ * @param serverClientID The fake server client idenfitier for the app.
+ * @param hostedDomain The fake hosted domain for the app.
+ * @param openIDRealm The fake OpenID realm for the app.
+ */
+- (instancetype)initWithClientID:(nullable id)clientID
+                  serverClientID:(nullable id)serverClientID
+                    hostedDomain:(nullable id)hostedDomain
+                     openIDRealm:(nullable id)openIDRealm
+    NS_DESIGNATED_INITIALIZER;
+
+/**
+ * @fn init:
+ * @brief Initializes a GIDFakeMainBundle object with `nil` to all of the designated initializer's parameters.
+ */
+- (instancetype)init;
+/**
+ * @fn startFaking:
+ * @brief Starts faking [NSBundle mainBundle]
+ */
+- (void)startFaking;
+
 /**
  * @fn startFakingWithClientID:
  * @brief Starts faking [NSBundle mainBundle]
  * @param clientID The fake client idenfitier for the app.
  */
-- (void)startFakingWithClientID:(NSString *)clientID;
+- (void)startFakingWithClientID:(nullable NSString *)clientID;
 
 /**
  * @fn stopFaking
@@ -87,9 +114,11 @@
  * @param hostedDomain The fake hosted domain for the app.
  * @param openIDRealm The fake OpenID realm for the app.
  */
-- (void)fakeWithClientID:(id)clientID
-          serverClientID:(id)serverClientID
-            hostedDomain:(id)hostedDomain
-             openIDRealm:(id)openIDRealm;
+- (void)fakeWithClientID:(nullable id)clientID
+          serverClientID:(nullable id)serverClientID
+            hostedDomain:(nullable id)hostedDomain
+             openIDRealm:(nullable id)openIDRealm;
 
 @end
+
+NS_ASSUME_NONNULL_END

GoogleSignIn/Tests/Unit/GIDFakeMainBundle.m

@@ -37,16 +37,38 @@ @implementation GIDFakeMainBundle {
   NSMutableDictionary *_fakeConfig;
 }
 
-- (void)startFakingWithClientID:(NSString *)clientId {
-  _clientId = clientId;
+- (instancetype)initWithClientID:(nullable id)clientID
+                  serverClientID:(nullable id)serverClientID
+                    hostedDomain:(nullable id)hostedDomain
+                     openIDRealm:(nullable id)openIDRealm {
+  self = [super init];
+
+  if (self) {
+    _clientId = clientID;
 
+    _fakeConfig = clientID ? [@{ @"GIDClientID" : clientID } mutableCopy] : [@{} mutableCopy];
+
+    [self fakeWithClientID:clientID
+            serverClientID:serverClientID
+              hostedDomain:hostedDomain
+               openIDRealm:openIDRealm];
+  }
+  return self;
+}
+
+- (instancetype)init {
+  return [self initWithClientID:nil
+                 serverClientID:nil
+                   hostedDomain:nil
+                    openIDRealm:nil];
+}
+
+- (void)startFaking {
   _fakedKeys = @[ kCFBundleURLTypesKey,
                   kConfigClientIDKey,
                   kConfigServerClientIDKey,
                   kConfigHostedDomainKey,
                   kConfigOpenIDRealmKey ];
-
-  _fakeConfig = [@{ @"GIDClientID" : clientId } mutableCopy];
 
   [GULSwizzler swizzleClass:[NSBundle class]
                    selector:@selector(objectForInfoDictionaryKey:)
@@ -62,6 +84,14 @@ - (void)startFakingWithClientID:(NSString *)clientId {
   }];
 }
 
+- (void)startFakingWithClientID:(nullable NSString *)clientId {
+  _clientId = clientId;
+
+  _fakeConfig = clientId ? [@{ @"GIDClientID" : clientId } mutableCopy] : [@{} mutableCopy];
+
+  [self startFaking];
+}
+
 - (void)stopFaking {
   [GULSwizzler unswizzleClass:[NSBundle class]
                      selector:@selector(objectForInfoDictionaryKey:)

GoogleSignIn/Tests/Unit/GIDSignInTest.m

@@ -286,12 +286,14 @@ - (void)setUp {
 #elif TARGET_OS_OSX
   _presentingWindow = OCMStrictClassMock([NSWindow class]);
 #endif // TARGET_OS_IOS || TARGET_OS_MACCATALYST
-  _authState = OCMStrictClassMock([OIDAuthState class]);
+
+  // TODO: Fix strict mocks from carrying forward to subsequent tests. (#410)
+  _authState = OCMClassMock([OIDAuthState class]);
   OCMStub([_authState alloc]).andReturn(_authState);
   OCMStub([_authState initWithAuthorizationResponse:OCMOCK_ANY]).andReturn(_authState);
   _tokenResponse = OCMStrictClassMock([OIDTokenResponse class]);
   _tokenRequest = OCMStrictClassMock([OIDTokenRequest class]);
-  _authorization = OCMStrictClassMock([GTMAuthSession class]);
+  _authorization = OCMClassMock([GTMAuthSession class]);
   _keychainStore = OCMStrictClassMock([GTMKeychainStore class]);
   OCMStub(
     [_keychainStore retrieveAuthSessionWithItemName:OCMOCK_ANY error:OCMArg.anyObjectRef]