TypedPaths.Generator 1.1.0

TypedPaths.Generator

A Roslyn source generator that turns configured folder trees into strongly typed path constants at compile time. Each configured folder becomes a nested static class (for example Src, Template) so you can avoid magic strings.

What you get

Given a structure like:

/src
  Template1.anyext
  folderA/
    Template2.anyext
  folderB/
    Template3.anyext
    Template4.anyext
/template
  email/
    welcome.txt
  sms/
    otp.txt

the generator emits one file per root folder (TypedPaths.Src.g.cs, TypedPaths.Template.g.cs, ...), each contributing to the same partial root class:

// TypedPaths.Src.g.cs
namespace TypedPaths;

public static partial class TypedPaths
{
    public static class Src
    {
        public const string Template1 = "src/Template1.anyext";
        public static class FolderA
        {
            public const string Template2 = "src/folderA/Template2.anyext";
        }
        public static class FolderB
        {
            public const string Template3 = "src/folderB/Template3.anyext";
            public const string Template4 = "src/folderB/Template4.anyext";
        }
    }
}

// TypedPaths.Template.g.cs
namespace TypedPaths;

public static partial class TypedPaths
{
    public static class Template
    {
        public static class Email
        {
            public const string Welcome = "template/email/welcome.txt";
        }
        public static class Sms
        {
            public const string Otp = "template/sms/otp.txt";
        }
    }
}

So you can use TypedPaths.Src.FolderA.Template2 and TypedPaths.Template.Email.Welcome instead of raw string paths.

Requirements

• .NET 8 (or the TFM your project uses; the generator targets .NET Standard 2.0)
• MSBuild / SDK-style projects

Setup

Option A: consume from NuGet (recommended)

<ItemGroup>
  <PackageReference Include="TypedPaths.Generator" Version="1.0.0" />
</ItemGroup>

<ItemGroup>
  <TypedPathsFolder Include="/src" ClassName="Src" />
  <TypedPathsFolder Include="/template" />
</ItemGroup>

TypedPaths.Generator.targets (from the package buildTransitive assets) maps these folders to AdditionalFiles and Content items for generation.

Option B: local project reference (repository development)

<ItemGroup>
  <ProjectReference Include="..\TypedPaths.Generator\TypedPaths.Generator.csproj"
                    OutputItemType="Analyzer"
                    ReferenceOutputAssembly="false" />
</ItemGroup>

<ItemGroup>
  <TypedPathsFolder Include="/src" ClassName="Src" />
  <TypedPathsFolder Include="/template" />
</ItemGroup>

<Import Project="..\TypedPaths.Generator\buildTransitive\TypedPaths.Generator.targets"
        Condition="Exists('..\TypedPaths.Generator\buildTransitive\TypedPaths.Generator.targets')" />

The explicit <Import /> is important for local project reference scenarios so folder declarations are translated into AdditionalFiles consistently during local builds.

Build the project; the generator runs and adds TypedPaths.*.g.cs files to the compilation.

Usage in code

The generated type is in namespace TypedPaths, and the root class is also named TypedPaths. To avoid name clashes, use an alias:

using TypedPathsRoot = TypedPaths.TypedPaths;

// Use as const strings
string path = TypedPathsRoot.Src.FolderA.Template2;  // "src/folderA/Template2.anyext"
string emailTemplate = TypedPathsRoot.Template.Email.Welcome; // "template/email/welcome.txt"

// e.g. resolve to full path
var fullPath = Path.Combine(projectRoot, TypedPathsRoot.Src.FolderA.Template2);

Naming rules

• Folder and file names become PascalCase identifiers.
• Invalid identifier characters are dropped or split; leading digits get a _ prefix.
• Duplicate names in the same scope get suffixes: _2, _3, etc.
• Extensions are stripped from member names but kept in the path string.

Repository layout

Build and test

dotnet restore
dotnet build
dotnet test

Run the sample:

dotnet run --project TypedPaths.Generator.Sample

License

See the repository for license information.