Nearly every headless UI test opened with the same four-line prologue
(resolve the shared MainWindow, show it, cast its DataContext, wait for the
assembly list), then repeated the corelib lookup, the EnsureLazyChildren +
Children.OfType<T>().Single() drill, the registry single-by-header lookups,
and the open-an-assembly-and-wait dance. The duplication made the intent of
each test hard to see and every signature tweak a suite-wide edit.
Collapse those into TestHarness (BootAsync, OpenAssemblyAsync, GetCommand,
GetEntry) and TreeNavigation extensions (FindCoreLib, GetChild<T>, Expand<T>),
then apply them across the suite. Net ~865 lines of boilerplate removed with
no change in behaviour; the full headless suite stays green.
Every_ExportToolbarCommand_Resolves_An_Icon used GetField against
ILSpy.Avalonia.Images.Images to verify every [ExportToolbarCommand]'s
ToolbarIcon resolves to a live IImage. Images.Images currently
declares its icons as static readonly fields, but a future refactor
could lazify them into properties (we explored that path earlier in
this session before reverting). Accept either FieldInfo or
PropertyInfo so the test keeps holding under that refactor.
Assisted-by: Claude:claude-opus-4-7:Claude Code
Imports the three SVG assets that were missing from `ILSpy.Avalonia/Assets/Icons/`
and registers them in `Images/Images.cs`, so the MEF-injected toolbar buttons
for "Reload all assemblies", "Sort assembly list by name", and "Collapse all
tree nodes" now render their icons instead of falling back to the tooltip text
(`MainToolBar.axaml.cs:226` `ResolveIcon` returned null for these). Adds a
regression test asserting every `[ExportToolbarCommand]`'s `ToolbarIcon`
resolves to a real `IImage` field on the registry.
Two missing toolbar buttons (Manage Assembly Lists, Show Search) and an
incorrect button order; the layout now mirrors WPF MainToolBar.xaml +
InitToolbar exactly. Also fixes an InitializeButtons no-op under
Avalonia.Headless (Loaded never fired; switched to AttachedToVisualTree).
Assisted-by: Claude:claude-opus-4-7:Claude Code
Siegfried Pammer