Refactor for cross platform port (#3641)

[lextm]

Typical changes needed by the cross platform port are,

1. A trivial namespace rename (TextView was both a control name and a namespace).
2. A few types were moved to their own source files, either easy to be replaced in the cross platform project folder, or add as link.
3. Split a few key classes into multiple source files, so that their WPF specific parts can be easily replaced in the cross platform project.

Still a work-in-progress, but should be ready to review and merge as it doesn't change anything fundamental on the WPF side.

[christophwille]

Why that moving around? namespace ICSharpCode.ILSpy.TextView => namespace ICSharpCode.ILSpy.TextViewControl

[lextm]

Project Rover uses two compiler tricks to enable source file reuse without heavy modifications,

• Global using statements
• Empty namespaces

However, such tricks fail easily when a type has the same name as an existing namespace. The term TextView happens to be hitting this problem.

I will see how much effort it takes to avoid this namespace change though. Will provide an update once I have some results.

[lextm]

Reverted the namespace changes, but one more extra file to maintain in the cross platform port.

[Copilot]

Pull request overview

This pull request refactors the ILSpy codebase to support cross-platform porting by separating WPF-specific code from platform-independent logic. The refactoring maintains existing functionality while restructuring code to enable easier platform abstraction.

Key Changes

• Split multiple classes into platform-specific (.wpf.cs) and shared (.cs) files to isolate WPF dependencies
• Extracted nested classes and extension methods into separate files for better modularity and platform-specific replacement
• Added IList interface implementation to SharpTreeNodeCollection for cross-platform binding compatibility

Reviewed changes

Copilot reviewed 35 out of 35 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
ILSpy/Views/OpenFromGacDialog.xaml.cs	Removed nested GacEntry class (extracted to separate file) and unused using statement
ILSpy/Views/GacEntry.cs	New file containing extracted GacEntry class nested within OpenFromGacDialog partial class
ILSpy/ViewModels/TabPageModelExtensions.wpf.cs	New file with WPF-specific Focus extension method for TabPageModel
ILSpy/ViewModels/TabPageModelExtensions.cs	New file with platform-independent TabPageModel extension methods
ILSpy/ViewModels/TabPageModel.cs	Removed TabPageModelExtensions static class (extracted to separate files) and unused using statements
ILSpy/ViewModels/PaneModel.cs	Removed Pane static class with WPF dependency properties (extracted to separate file) and unused using statement
ILSpy/ViewModels/Pane.cs	New file containing extracted Pane static class with WPF dependency properties
ILSpy/ViewModels/LegacyToolPaneModel.cs	Removed unused System.Windows using statement
ILSpy/ViewModels/DebugStepsPaneModel.cs	Removed unused System.Windows using statement
ILSpy/TreeNodes/AssemblyListTreeNode.wpf.cs	New file with WPF-specific drag-drop implementation for AssemblyListTreeNode
ILSpy/TreeNodes/AssemblyListTreeNode.cs	Made class partial, removed drag-drop methods (moved to .wpf.cs file) and unused using statements
ILSpy/TextView/VisualLineReferenceText.wpf.cs	New file with WPF-specific cursor handling for VisualLineReferenceText
ILSpy/TextView/VisualLineReferenceText.cs	New file with platform-independent VisualLineReferenceText implementation
ILSpy/TextView/ViewState.cs	New file containing extracted ViewState class from DecompilerTextView
ILSpy/TextView/ReferenceElementGenerator.cs	Removed nested VisualLineReferenceText class (extracted to separate files)
ILSpy/TextView/IBracketSearcher.cs	New file containing extracted IBracketSearcher interface
ILSpy/TextView/DefaultBracketSearcher.cs	New file containing extracted DefaultBracketSearcher class
ILSpy/TextView/DecompilerTextView.cs	Removed ViewState class (extracted to separate file)
ILSpy/TextView/BracketSearchResult.cs	New file containing extracted BracketSearchResult class
ILSpy/TextView/BracketHighlightRenderer.cs	Removed bracket-related classes (extracted to separate files) and added null-safety for resource loading
ILSpy/SmartTextOutputExtensions.cs	New file containing extracted SmartTextOutputExtensions static class
ILSpy/Search/ShowSearchCommand.cs	New file containing extracted ShowSearchCommand class with debug logging
ILSpy/Search/SearchPaneModel.cs	Added [Export] attribute and made class partial
ILSpy/Search/SearchPane.xaml.cs	Removed ShowSearchCommand class (extracted to separate file) and unused using statement
ILSpy/Options/DisplaySettings.cs	Added CROSS_PLATFORM conditional compilation for font handling
ILSpy/Languages/CSharpLanguage.wpf.cs	New file with WPF-specific AddWarningMessage implementation
ILSpy/Languages/CSharpLanguage.cs	Made class partial and removed AddWarningMessage method (moved to .wpf.cs file)
ILSpy/ISmartTextOutput.cs	Removed SmartTextOutputExtensions class (extracted to separate file) and unused using statements
ILSpy/Docking/DockWorkspace.wpf.cs	New file with WPF-specific docking and layout management implementation
ILSpy/Docking/DockWorkspace.cs	Made class partial, changed Export attribute to explicit type, removed WPF-specific methods and using statements
ILSpy/AssemblyTree/AssemblyTreeModel.wpf.cs	New file with WPF-specific constructor and initialization logic
ILSpy/AssemblyTree/AssemblyTreeModel.cs	Made class partial, removed constructor and LoadInitialAssemblies method, added TODO comments
ILSpy/AboutPage.cs	Added CROSS_PLATFORM conditional compilation for binding and image loading
ICSharpCode.ILSpyX/TreeView/SharpTreeNodeCollection.cs	Added IList interface implementation with collection manipulation methods
ICSharpCode.ILSpyX/TreeView/SharpTreeNode.cs	Added ViewChildren property and LoadingTreeNode class for cross-platform tree view binding

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[christophwille]

Fyi, we run Copilot reviews on almost all PRs these days to see how it changes over time (quality-wise), so expect nuggets and duds.

[lextm]

@christophwille It actually provides some useful insights. I am still working on the repo reconfiguration, so will take care of them later.

[christophwille]

No need to rush anything. A well-thought-out & tested approach is appreciated.

[Copilot]

Pull request overview

Copilot reviewed 55 out of 55 changed files in this pull request and generated 6 comments.

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