Source generator not working?

<Project Sdk="Microsoft.NET.Sdk">

    <PropertyGroup>
        <TargetFramework>netstandard2.0</TargetFramework>
        <LangVersion>10.0</LangVersion>
        <Nullable>enable</Nullable>
        <ImplicitUsings>enable</ImplicitUsings>
    </PropertyGroup>

    <ItemGroup>
        <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Workspaces"
                          Version="4.0.1"
                          PrivateAssets="all" />
    </ItemGroup>
</Project>

<ProjectReference Include="..\SourceGen\SouceGen.csproj" 
                          OutputItemType="Analyzer"
                          ReferenceOutputAssembly="false"/>

[Generator]
public class TestingGenerator : IIncrementalGenerator
{
    public void Initialize(IncrementalGeneratorInitializationContext context)
    {
        throw new Exception("Test Exception!");
    }
}