public async Task ReactInstanceManager_ArgumentChecks()
{
ReactInstanceManager manager = null;
await DispatcherHelpers.CallOnDispatcherAsync(() => manager = CreateReactInstanceManager());
await AssertEx.ThrowsAsync <ArgumentNullException>(
async() => await DispatcherHelpers.CallOnDispatcherAsync(() =>
manager.AttachMeasuredRootViewAsync(null)),
ex => Assert.AreEqual("rootView", ex.ParamName));
await AssertEx.ThrowsAsync <ArgumentNullException>(
async() => await DispatcherHelpers.CallOnDispatcherAsync(() =>
manager.CreateAllViewManagers(null)),
ex => Assert.AreEqual("reactContext", ex.ParamName));
await AssertEx.ThrowsAsync <ArgumentNullException>(
async() => await DispatcherHelpers.CallOnDispatcherAsync(() =>
manager.DetachRootViewAsync(null)),
ex => Assert.AreEqual("rootView", ex.ParamName));
await DispatcherHelpers.CallOnDispatcherAsync(async() => await DisposeInstanceManager(manager));
}