Remove InternalsVisibleTo attributes for .NET MAUI Community Toolkit

[jfversluis]

Note

Are you waiting for the changes in this PR to be merged?
It would be very helpful if you could test the resulting artifacts from this PR and let us know in a comment if this change resolves your issue. Thank you!

Description of Change

Removes all InternalsVisibleTo attributes that grant the .NET MAUI Community Toolkit access to internal APIs. This is the same change as #33442 (which was reverted in #34047 for .NET 10 SR4), now targeting net11.0 to give the toolkit team time to migrate.

Previous attempts:

• Remove InternalsVisibleTo for Toolkit #28994 — First removal (reverted in Revert "Remove InternalsVisibleTo for Toolkit" #29321 because toolkit wasn't updated)
• Make internal types used by MAUI Toolkit public #29443 — Made some types public (ITextElement, ICornerElement, etc.)
• Remove InternalsVisibleTo attributes for .NET MAUI Community Toolkit #33442 — Second removal in SR4 (reverted in Revert "Remove InternalsVisibleTo attributes for .NET MAUI Community … #34047 because toolkit still wasn't updated)

Files Modified

File	Entries Removed
src/Controls/src/Core/Properties/AssemblyInfo.cs	6 + 1 duplicate Controls.TestCases.HostApp
src/Controls/src/Xaml/Properties/AssemblyInfo.cs	6
src/Essentials/src/AssemblyInfo/AssemblyInfo.shared.cs	5
src/Core/src/Properties/AssemblyInfo.cs	5

Total: 22 InternalsVisibleTo declarations removed for CommunityToolkit.Maui, .Core, .Embedding, .UnitTests, .Markup, .Markup.UnitTests.

Internal APIs Still Used by the Toolkit

Can be fixed on the toolkit side (public alternatives exist):

API	Toolkit Usage	Public Alternative
InvalidateMeasureInternal(InvalidationTrigger)	AvatarView	Use public InvalidateMeasure()
XamlParseException(string, IServiceProvider)	AppThemeResourceExtension	Use public ctor with IXmlLineInfo
GetDefaultFontSize()	AvatarView	Resolve IFontManager.DefaultFontSize from services
RequireFontManager()	Snackbar, UIFontExtensions	Resolve IFontManager from MauiContext.Services
AppThemeBinding	AppThemeObject	Already public on net11.0
GetTargetOrDefault()	Snackbar	Toolkit already has its own copy

Requires MAUI to provide public alternatives:

API	Toolkit Usage	Suggested Action
FontElement (static class)	AvatarView — 4 BindableProperty defs	Make public
TextElement (static class)	AvatarView — 3 BindableProperty defs	Make public
ImageElement (static class)	AvatarView, TouchBehavior, ImageTouchBehavior	Make public
IResourcesProvider (interface)	AppThemeResourceExtension	Make public
ImageSource.CancellationTokenSource	GravatarImageSource	Change to protected
StreamWrapper	HttpClientExtensions	Make public or provide alternative

Issues Fixed

Context: #29444, #34048

cc @TheCodeTraveler

[Copilot]

Pull request overview

This PR removes all InternalsVisibleTo attributes that grant the .NET MAUI Community Toolkit access to internal APIs. This is the third attempt to make this change, now targeting the net11.0 branch to provide the toolkit team sufficient time to migrate away from internal API dependencies.

Changes:

• Removed 22 InternalsVisibleTo declarations across 4 AssemblyInfo files for CommunityToolkit assemblies
• Removed duplicate Controls.TestCases.HostApp entry from Controls/Core AssemblyInfo
• Preserved all other InternalsVisibleTo entries for MAUI's own test and compatibility assemblies

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
src/Essentials/src/AssemblyInfo/AssemblyInfo.shared.cs	Removed 5 CommunityToolkit InternalsVisibleTo entries
src/Core/src/Properties/AssemblyInfo.cs	Removed 5 CommunityToolkit InternalsVisibleTo entries
src/Controls/src/Xaml/Properties/AssemblyInfo.cs	Removed 6 CommunityToolkit InternalsVisibleTo entries
src/Controls/src/Core/Properties/AssemblyInfo.cs	Removed 6 CommunityToolkit entries + 1 duplicate Controls.TestCases.HostApp entry

[Copilot]

According to issue #29444, the file src/Controls/src/Core/ILineHeightElementInternal.cs should be deleted as part of removing InternalsVisibleTo attributes. This file was only kept to provide a transition path for the toolkit and is now obsolete. The interface has been replaced by Microsoft.Maui.Controls.ILineHeightElement and is no longer used within the MAUI codebase.

[jfversluis]

Moving this to draft, the Toolkit team can get the resulting artifacts from this for testing to make sure that all APIs are replaced.