Strip '[Embedded]' when types are public

Author: Sergio0694

src/PolySharp.SourceGenerators/PolyfillsGenerator.Polyfills.cs

@@ -61,6 +61,11 @@ where resourceName.StartsWith("PolySharp.SourceGenerators.EmbeddedResources.Runt
     /// </summary>
     private static readonly Regex ExcludeFromCodeCoverageRegex = new(@" *\[global::System\.Diagnostics\.CodeAnalysis\.ExcludeFromCodeCoverage\]\r?\n", RegexOptions.Compiled);
 
+    /// <summary>
+    /// The <see cref="Regex"/> to find all <see cref="EmbeddedAttribute"/> uses.
+    /// </summary>
+    private static readonly Regex EmbeddedAttributeRegex = new(@" *\[global::Microsoft\.CodeAnalysis\.Embedded\]\r?\n", RegexOptions.Compiled);
+
     /// <summary>
     /// The dictionary of cached sources to produce.
     /// </summary>
@@ -282,6 +287,9 @@ private void EmitGeneratedType(SourceProductionContext context, GeneratedType ty
                     // rewriter, or just by retrieving the type declaration syntax and updating the modifier tokens, but since the
                     // change is so minimal, it can very well just be done this way to keep things simple, that's fine in this case.
                     adjustedSource = adjustedSource.Replace(" internal ", " public ");
+
+                    // If types are public, we also need to strip the '[Embedded]' attributes, as it's only allowed on public types
+                    adjustedSource = EmbeddedAttributeRegex.Replace(adjustedSource, "");
                 }
 
                 if ((type.FixupType & SyntaxFixupType.RemoveMethodImplAttributes) != 0)

src/PolySharp.SourceGenerators/PrivatePolyfills/EmbeddedAttribute.cs

@@ -0,0 +1,12 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+
+namespace Microsoft.CodeAnalysis;
+
+/// <summary>
+/// Marks a type as "embedded", meaning it won't ever be visible from other assemblies.
+/// </summary>
+[AttributeUsage(AttributeTargets.All)]
+internal sealed class EmbeddedAttribute : Attribute;