To audit what each UI test actually exercises, every step now snapshots the
live window to <TestFixtureName>/<TestName>_<NN>_<ShortDescription>.png: a
booted frame (emitted automatically by TestHarness.BootAsync), one after each
state-changing action, and one before each assertion. Flip ILSPY_TESTS_VISIBLE=1
to render the filmstrip; it lands under %TEMP%/ilspy-test-captures (overridable
via ILSPY_TEST_CAPTURES).
The step number and fixture/test name are derived automatically so inserting a
breakpoint never renumbers the rest. The identity is recorded up front from the
real ITest in an ITestAction hook rather than read live: NUnit's
TestContext.CurrentContext does not flow onto async continuations, so a capture
after an await would otherwise collide under the ad-hoc context. And when
rendering is off the whole call is a true no-op -- not even a dispatcher pump --
so instrumenting a test can never perturb the navigation/tab timing it asserts
on. Full headless suite stays green.
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.
Siegfried Pammer