Update readme

Author: linkdotnet

src/bunit.generators/README.md

@@ -1,4 +1,57 @@
-# Tips for developing with the generator
+# bUnit Generators
+
+This package contains source generators for bUnit, to make it easier and more convenient to write tests. 
+
+## `AddGeneratedStub` Generator
+This generator adds the ability to automatically generate stubs for a given type. This comes in handy, when dealing
+with 3rd party components that might need an extensive setup. Here a small example:
+
+Given the following component
+```razor
+<ThirdPartyText Text="@count" />
+<button @onclick="IncrementCount">Increase by one</button>
+@code {
+ private int count;
+ 
+ private void IncrementCount()
+ {
+	 count++;
+ }
+}
+```
+
+If `ThirdPartyText` is a 3rd party component, that needs a lot of setup, it might be easier to just stub it out:
+
+```csharp
+[Fact]
+public void Text_button_gets_initial_count()
+{
+    // This call will automatically generate a stub for the ThirdPartyButton component
+    // with the name "ThirdPartyButtonStub"
+    ComponentFactories.AddGeneratedStub<ThirdPartyText>();
+    var cut = Render<Counter>(@<Counter />);
+    
+    cut.Find("button").Click();
+    
+    // Retrieves the stub from the render tree and checks if the text is "1"
+    cut.FindComponent<ThirdPartyTextStub>().Instance.Text.Should().Be("1");
+}
+```
+
+### Setup
+To use the generator, the **Interceptor** feature has to be used inside the csproj file:
+
+```xml
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFramework>net8.0</TargetFramework>
+		<!-- This line is required to enable the generator and interceptor -->
+		<InterceptorsPreviewNamespaces>$(InterceptorsPreviewNamespaces);Bunit</InterceptorsPreviewNamespaces>
+```
+
+## Developer notes
+
+### Tips for developing with the generator
 
 When changing the source generator, to see the effect, clearing the build cache may be necessary: