Fix credential provider enum (#2988)

Author: nirinchev

CHANGELOG.md

@@ -4,7 +4,9 @@
 * None
 
 ### Fixed
-* None
+* Fixed an issue introduced in 10.15.0 that would prevent non-anonoymous user authentication against Atlas App Services. (Issue [#2987](https://github.com/realm/realm-dotnet/issues/2987))
+* Added override to `User.ToString()` that outputs the user id and provider. (PR [#2988](https://github.com/realm/realm-dotnet/pull/2988))
+* Added == and != operator overloads to `User` that matches the behavior of `User.Equals`. (PR [#2988](https://github.com/realm/realm-dotnet/pull/2988))
 
 ### Compatibility
 * Realm Studio: 12.0.0 or later.

Realm/Realm/Sync/Credentials.cs

@@ -40,43 +40,43 @@ public enum AuthProvider
             /// <summary>
             /// OAuth2-based mechanism for logging in with an existing Facebook account.
             /// </summary>
-            Facebook = 1,
+            Facebook = 2,
 
             /// <summary>
             /// Mechanism for logging in with an existing Google account using an auth code or Id token.
             /// </summary>
-            Google = 2,
+            Google = 3,
 
             /// <summary>
             /// OAuth2-based mechanism for logging in with an Apple ID.
             /// </summary>
-            Apple = 3,
+            Apple = 4,
 
             /// <summary>
             /// Allow users to log in with JWT-based credentials generated by a service external to Realm.
             /// </summary>
-            JWT = 4,
+            JWT = 5,
 
             /// <summary>
             /// Mechanism for authenticating with an email and a password.
             /// </summary>
-            EmailPassword = 5,
+            EmailPassword = 6,
 
             /// <summary>
             /// Allow users to log in with arbitrary credentials according to custom authentication logic that you define
             /// on the server.
             /// </summary>
-            Function = 6,
+            Function = 7,
 
             /// <summary>
             /// Mechanism for logging in with API keys generated by the client SDK.
             /// </summary>
-            ApiKey = 7,
+            ApiKey = 8,
 
             /// <summary>
             /// Mechanism for logging in with API keys generated in the server UI.
             /// </summary>
-            ServerApiKey = 8,
+            ServerApiKey = 9,
 
             /// <summary>
             /// A provider that is not among the well known provider types. This is most likely the result of the server
@@ -88,9 +88,15 @@ public enum AuthProvider
         /// <summary>
         /// Creates credentials representing an anonymous user.
         /// </summary>
+        /// <param name="reuseExisting">
+        /// A value indicating whether anonymous users should be reused. Passing <c>true</c> means that multiple calls to
+        /// <c>app.LoginAsync(Credentials.Anonymous())</c> will return the same anonymous user as long as that user hasn't
+        /// logged out. If <paramref name="reuseExisting"/> is <c>false</c>, every time you call <see cref="App.LogInAsync(Credentials)"/>,
+        /// a new user will be created on the server.
+        /// </param>
         /// <returns>A Credentials that can be used to authenticate an anonymous user.</returns>
         /// <seealso href="https://docs.mongodb.com/realm/authentication/anonymous/">Anonymous Authentication Docs</seealso>
-        public static Credentials Anonymous() => new Credentials(AuthProvider.Anonymous);
+        public static Credentials Anonymous(bool reuseExisting = true) => new(AuthProvider.Anonymous, additionalInfo: reuseExisting.ToString().ToLower());
 
         /// <summary>
         /// Creates credentials representing a login using a Facebook access token.

Realm/Realm/Sync/User.cs

@@ -274,25 +274,25 @@ public async Task<User> LinkCredentialsAsync(Credentials credentials)
         }
 
         /// <inheritdoc />
-        public override bool Equals(object obj)
-        {
-            return Equals(obj as User);
-        }
+        public override bool Equals(object obj) => Equals(obj as User);
 
         /// <summary>
         /// Determines whether this instance and another <see cref="User"/> instance are equal by comparing their identities.
         /// </summary>
         /// <param name="other">The <see cref="User"/> instance to compare with.</param>
         /// <returns>true if the two instances are equal; false otherwise.</returns>
-        public bool Equals(User other)
-        {
-            return Id.Equals(other?.Id);
-        }
+        public bool Equals(User other) => Id.Equals(other?.Id);
 
         /// <inheritdoc />
-        public override int GetHashCode()
+        public override int GetHashCode() => Id.GetHashCode();
+
+        public static bool operator ==(User user1, User user2) => user1?.Id == user2?.Id;
+
+        public static bool operator !=(User user1, User user2) => !(user1 == user2);
+
+        public override string ToString()
         {
-            return Id.GetHashCode();
+            return $"User {Id}, State: {State}, Provider: {Provider}";
         }
 
         /// <summary>

Tests/Realm.Tests/Sync/UserManagementTests.cs

@@ -951,6 +951,80 @@ public void UserCustomData_Generic()
             });
         }
 
+        [Test]
+        public void UserAnonymous([Values(true, false)] bool firstReuse, [Values(true, false)] bool secondReuse)
+        {
+            SyncTestHelpers.RunBaasTestAsync(async () =>
+            {
+                var user = await DefaultApp.LogInAsync(Credentials.Anonymous(reuseExisting: firstReuse));
+                Assert.That(user, Is.Not.Null);
+                Assert.That(user.Id, Is.Not.Null);
+
+                var anotherUser = await DefaultApp.LogInAsync(Credentials.Anonymous(reuseExisting: secondReuse));
+                Assert.That(anotherUser, Is.Not.Null);
+                Assert.That(anotherUser.Id, Is.Not.Null);
+
+                // We only expect both users to be the same if they both reused their credentials
+                Assert.That(user.Id == anotherUser.Id, Is.EqualTo(secondReuse), $"Expected Ids to {(secondReuse ? string.Empty : "not ")}match");
+                Assert.That(user == anotherUser, Is.EqualTo(secondReuse), $"Expected Users to {(secondReuse ? string.Empty : "not ")}match");
+            });
+        }
+
+        [Test]
+        public void UserAnonymous_CombiningReuseAndNotReuse()
+        {
+            SyncTestHelpers.RunBaasTestAsync(async () =>
+            {
+                var anonA = await DefaultApp.LogInAsync(Credentials.Anonymous(reuseExisting: false));
+                var reusedA1 = await DefaultApp.LogInAsync(Credentials.Anonymous());
+                var reusedA2 = await DefaultApp.LogInAsync(Credentials.Anonymous());
+                var anonB = await DefaultApp.LogInAsync(Credentials.Anonymous(reuseExisting: false));
+                var reusedB = await DefaultApp.LogInAsync(Credentials.Anonymous());
+
+                Assert.That(anonA, Is.EqualTo(reusedA1));
+                Assert.That(anonA, Is.EqualTo(reusedA2));
+
+                Assert.That(anonB, Is.Not.EqualTo(anonA));
+                Assert.That(anonB, Is.EqualTo(reusedB));
+
+                await anonB.LogOutAsync();
+
+                Assert.That(anonB.State, Is.EqualTo(UserState.Removed));
+                Assert.That(reusedB.State, Is.EqualTo(UserState.Removed));
+
+                var reusedA3 = await DefaultApp.LogInAsync(Credentials.Anonymous());
+
+                Assert.That(reusedA3, Is.EqualTo(anonA));
+            });
+        }
+
+        [Test]
+        public void UserEqualsOverrides()
+        {
+            SyncTestHelpers.RunBaasTestAsync(async () =>
+            {
+                var user = await DefaultApp.LogInAsync(Credentials.Anonymous(reuseExisting: false));
+                var currentUser = DefaultApp.CurrentUser;
+
+                Assert.That(user.Id, Is.EqualTo(currentUser.Id));
+                Assert.That(user.Equals(currentUser));
+                Assert.That(user == currentUser);
+
+                var anotherUser = await DefaultApp.LogInAsync(Credentials.Anonymous(reuseExisting: false));
+                Assert.That(user.Id, Is.Not.EqualTo(anotherUser.Id));
+                Assert.That(user.Equals(anotherUser), Is.False);
+                Assert.That(user != anotherUser);
+            });
+        }
+
+        [Test]
+        public void UserToStringOverride()
+        {
+            var user = GetFakeUser();
+            Assert.That(user.ToString(), Does.Contain(user.Id));
+            Assert.That(user.ToString(), Does.Contain(user.Provider.ToString()));
+        }
+
         private class CustomDataDocument
         {
             [Preserve]

wrappers/src/app_cs.hpp

@@ -69,8 +69,10 @@ namespace binding {
         AppCredentials to_app_credentials() {
             switch (provider)
             {
-            case AuthProvider::ANONYMOUS:
-                return AppCredentials::anonymous();
+            case AuthProvider::ANONYMOUS: {
+                Utf16StringAccessor reuse_existing(additional_info, additional_info_len);
+                return AppCredentials::anonymous(reuse_existing == "true");
+            }
 
             case AuthProvider::FACEBOOK:
                 return AppCredentials::facebook(Utf16StringAccessor(token, token_len));