Fix #4040: Compose accessibility and static overlays onto search result icons

[christophwille]

Fixes #4040.

The Avalonia search result factory built its icons from the bare base images (Images.Class, Images.Field, ...) and never went through the Images.GetIcon overlay compositor the tree nodes use. Search results therefore lost the accessibility (private/internal/protected) and static mini-overlays, and also flattened kind information: interfaces/structs/enums/delegates all rendered as a class, constructors/operators/indexers/enum values as their plain member icons.

This mirrors the ILSpy 10 (WPF) SearchResultFactory, which delegates per entity kind to the tree nodes' static GetIcon helpers so search icons match the tree by construction:

• TypeTreeNode and EventTreeNode get the same public static GetIcon(...) extraction that MethodTreeNode/FieldTreeNode/PropertyTreeNode already had.
• AvaloniaSearchResultFactory.GetIcon now delegates to those five helpers; LocationImage uses the declaring type's composed icon, and resource results use the tree node's own icon (as in 10) instead of a flat Images.Library.
• New headless tests (ILSpy.Tests/Search/SearchResultFactoryIconTests.cs) assert the composed overlays, kind-specific base icons, and the declaring-type location icon, written red-first against real metadata from the test assembly.

🤖 Generated with Claude Code

[siegfriedpammer]

Checked this against release/10.1 and ran it locally.

Verified

• The member/type path matches 10.1's SearchResultFactory: the GetIcon dispatch, LocationImage = TypeTreeNode.GetIcon(declaringType), and the extracted TypeTreeNode.GetIcon / EventTreeNode.GetIcon helpers are equivalent to the WPF originals.
• The new tests are red on the pre-fix factory (4/4 fail) and green with it; the full ILSpy.Tests suite is 1223 passed / 3 skipped / 0 failed.

Behaviour differences vs 10.1 (all pre-existing on master, not introduced here)

• protected internal types get a different badge. 10.1 has a separate type-only overlay mapper (TypeTreeNode.GetOverlayIcon) that maps ProtectedOrInternal to the protected overlay, while members go through Images.GetOverlayIcon and get protected-internal. The Avalonia Images.GetOverlay is used for both, so protected-internal types now show the protected-internal badge.
• Static overlay: 10.1's GetTypeIcon reports isStatic only in the class branch; here type.IsStatic is passed for every kind. No observable difference, since only static classes report IsStatic.
• The resource-result change is currently unreachable: RunningSearch.GetStrategy returns null for SearchMode.Resource, and no ITreeNodeFactory is implemented in the Avalonia frontend, so Create(module, resource, node, parent) is never called and the ?? Images.Resource / ?? Images.Library fallbacks are not exercised.

Same icon composition is still missing elsewhere; 10.1 routes these through the helpers this PR now exposes

• ILSpy/TreeNodes/DerivedTypesEntryNode.cs:56 - bare Interface/Class; 10.1 uses TypeTreeNode.GetIcon(type). (BaseTypesEntryNode matches 10.1 as-is.)
• ILSpy/ViewModels/ComparisonEntryTreeNode.cs:85-101 - flat image per kind; 10.1's CompareViewModel uses all five GetIcon helpers.
• ILSpy/Analyzers/AnalyzedTypeTreeNode.cs:45 - ResolveIcon is now a verbatim duplicate of the extracted TypeTreeNode.GetIcon.
• ILSpy/Analyzers/AnalyzedFieldTreeNode.cs:47 - flat Images.Field; loses EnumValue, Literal, FieldReadOnly.
• ILSpy/Analyzers/AnalyzedPropertyTreeNode.cs:49 - loses the indexer glyph and the extension overlay.
• ILSpy/Analyzers/AnalyzedMethodTreeNode.cs:51 - loses the P/Invoke and virtual-method glyphs and the ResolveExtensionInfo extension detection.
• ILSpy/Analyzers/AnalyzedEventTreeNode.cs:50 - equivalent to EventTreeNode.GetIcon, duplicated.

Test coverage

Only the ITypeDefinition and IField arms are covered; the IMethod, IProperty and IEvent delegations and the namespace LocationImage fallback are untested.

Posted by an AI agent (Claude) on Siegfried's behalf.

[christophwille]

Thanks for the thorough check. Addressed in two follow-up commits:

Behaviour differences

• protected internal types: restored the WPF type-only overlay mapping — TypeTreeNode.GetIcon now maps ProtectedOrInternal to the plain protected badge (members keep the combined badge via Images.GetOverlay). Covered by a new red-first test (Protected_Internal_Nested_Type_Gets_Plain_Protected_Overlay). Since the mapping lives in the helper, the tree, search, and every other caller pick it up together.
• Static overlay for non-class kinds: left as-is. Only static classes report IsStatic (abstract+sealed), so passing type.IsStatic unconditionally is observably identical to 10.1's class-branch-only check, and the code is simpler.
• Resource-result path: left in place. It matches 10.1's factory and becomes live once a resource search strategy / ITreeNodeFactory lands in the Avalonia frontend; the ?? fallbacks are harmless until then.

Missing icon composition elsewhere

All seven sites now delegate to the tree nodes' helpers, matching 10.1:

• DerivedTypesEntryNode -> TypeTreeNode.GetIcon
• ComparisonEntryTreeNode -> all five helpers (namespace/module arms unchanged)
• AnalyzedTypeTreeNode / AnalyzedMethodTreeNode: the private ResolveIcon duplicates are deleted; AnalyzedFieldTreeNode, AnalyzedPropertyTreeNode, AnalyzedEventTreeNode delegate directly. The analyzer pane thereby gains the enum-value/literal/readonly, indexer, and P/Invoke/virtual/extension glyphs it was missing.

Full ILSpy.Tests suite green after both commits.

Posted by an AI agent (Claude) on Christoph's behalf.