public async Task EnsuresNonNullArguments()
            {
                var client = new RepositoryBranchesClient(Substitute.For<IApiConnection>());
                var newUsers = new BranchProtectionUserCollection() { "test" };

                await Assert.ThrowsAsync<ArgumentNullException>(() => client.AddProtectedBranchUserRestrictions(null, "repo", "branch", newUsers));
                await Assert.ThrowsAsync<ArgumentNullException>(() => client.AddProtectedBranchUserRestrictions("owner", null, "branch", newUsers));
                await Assert.ThrowsAsync<ArgumentNullException>(() => client.AddProtectedBranchUserRestrictions("owner", "repo", null, newUsers));
                await Assert.ThrowsAsync<ArgumentNullException>(() => client.AddProtectedBranchUserRestrictions("owner", "repo", "branch", null));

                await Assert.ThrowsAsync<ArgumentNullException>(() => client.AddProtectedBranchUserRestrictions(1, null, newUsers));
                await Assert.ThrowsAsync<ArgumentNullException>(() => client.AddProtectedBranchUserRestrictions(1, "branch", null));

                await Assert.ThrowsAsync<ArgumentException>(() => client.AddProtectedBranchUserRestrictions("", "repo", "branch", newUsers));
                await Assert.ThrowsAsync<ArgumentException>(() => client.AddProtectedBranchUserRestrictions("owner", "", "branch", newUsers));
                await Assert.ThrowsAsync<ArgumentException>(() => client.AddProtectedBranchUserRestrictions("owner", "repo", "", newUsers));

                await Assert.ThrowsAsync<ArgumentException>(() => client.AddProtectedBranchUserRestrictions(1, "", newUsers));
            }
            public void RequestsTheCorrectUrlWithRepositoryId()
            {
                var connection = Substitute.For<IApiConnection>();
                var client = new RepositoryBranchesClient(connection);
                var newUsers = new BranchProtectionUserCollection() { "test" };
                const string previewAcceptsHeader = "application/vnd.github.loki-preview+json";

                client.AddProtectedBranchUserRestrictions(1, "branch", newUsers);

                connection.Received()
                    .Post<IReadOnlyList<User>>(Arg.Is<Uri>(u => u.ToString() == "repositories/1/branches/branch/protection/restrictions/users"), Arg.Any<IReadOnlyList<string>>(), previewAcceptsHeader);
            }