Getting Started

To use this source generator include it as a source only dependency in your project.

<ItemGroup>
    <PackageReference Include="Tuxedo.SourceGenerator" Version="x.x.x">
        <PrivateAssets>all</PrivateAssets>
        <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
</ItemGroup>

Now we can build our first refined type.

Let's create a password string that must comply with some simple rules.

It must,

• Be at least 8 characters long
• Contain at least 1 uppercase letter
• Contain at least 1 number
• Contain at least 1 special character

To do this create a simple predicate method, It helps to do this on the partial struct that will eventually be the refined type.

So in this case that type will be called a PasswordString, it looks like this,

/// <summary>
/// A valid password string
/// </summary>
public readonly partial struct PasswordString
{
    // this is the definition of what makes a password string valid.
    // the name of the method combined with the type it operates on make up the name of the refined type
    // in this case PasswordString
    [Tuxedo.Refinement(
        "The string must be at least 8 characters long, contain at most 1 uppercase letter, number and special character. You provided '{value}'.",
        Name = nameof(PasswordString)
    )]
    private static bool IsValidPassword(string value)
    {
        if (value.Length < 8)
        {
            return false;
        }

        var hasUppercaseLetter = false;
        var hasNumber = false;
        var hasSpecialCharacter = false;
        foreach (var @char in value)
        {
            hasUppercaseLetter |= char.IsUpper(@char);
            hasNumber |= char.IsDigit(@char);
            hasSpecialCharacter |= !char.IsLetterOrDigit(@char) && !char.IsWhiteSpace(@char);
        }

        return hasUppercaseLetter && hasNumber && hasSpecialCharacter;
    }
}

Which can be used like this,

bool isValid = PasswordString.TryParse("12Da3%sd", out var password, out _);
Assert.True(isValid);
Assert.Equal("12Da3%sd", password.Value);