/// <summary>
/// Validates the specified <paramref name="username"/>, returning
/// any charcters that are not valid according to the rules set out
/// in the specified <paramref name="options"/>.
/// </summary>
/// <param name="username">The username to validate.</param>
/// <param name="options">The configuraton options to use during validation.</param>
/// <returns>Enumerable collection of invalid characters.</returns>
public static IEnumerable <char> GetInvalidCharacters(string username, UsernameOptions options)
{
if (username == null)
{
throw new ArgumentNullException(nameof(username));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
if (options.AllowAnyCharacter)
{
return(Array.Empty <char>());
}
var badCharacters = username.Distinct();
if (options.AllowAnyDigit)
{
badCharacters = badCharacters.Where(c => !Char.IsDigit(c));
}
if (options.AllowAnyLetter)
{
badCharacters = badCharacters.Where(c => !Char.IsLetter(c));
}
if (!string.IsNullOrEmpty(options.AdditionalAllowedCharacters))
{
badCharacters = badCharacters.Where(c => !options.AdditionalAllowedCharacters.Contains(c));
}
return(badCharacters);
}
public void UsingDefaultRules_IrregularEmailsNotAllowed(string email)
{
var options = new UsernameOptions()
{
AllowAnyCharacter = false
};
var result = UsernameCharacterValidator.GetInvalidCharacters(email, options);
result.Should().HaveCountGreaterOrEqualTo(1);
}
public void UsingDefaultRules_AcceptsValidUsernames(string email)
{
var options = new UsernameOptions()
{
AllowAnyCharacter = false
};
var result = UsernameCharacterValidator.GetInvalidCharacters(email, options);
result.Should().BeEmpty();
}
public void AllowAny_AcceptsAnything(string email)
{
var options = new UsernameOptions()
{
AllowAnyCharacter = true
};
var result = UsernameCharacterValidator.GetInvalidCharacters(email, options);
result.Should().BeEmpty();
}
public void WhenAllowsSpecificChars_ReturnInvalid(string email, string expected)
{
var options = new UsernameOptions()
{
AdditionalAllowedCharacters = "dog",
AllowAnyCharacter = false,
AllowAnyLetter = false,
AllowAnyDigit = false
};
var result = UsernameCharacterValidator.GetInvalidCharacters(email, options);
result.Should().BeEquivalentTo(expected);
}
public void WhenAllowsOnlyDigit_ReturnsNonDigits(string email, string expected)
{
var options = new UsernameOptions()
{
AdditionalAllowedCharacters = null,
AllowAnyCharacter = false,
AllowAnyLetter = false,
AllowAnyDigit = true
};
var result = UsernameCharacterValidator.GetInvalidCharacters(email, options);
result.Should().BeEquivalentTo(expected);
}
