it: test focus moving

src/it/test_utils/test_expected_event.rs

@@ -1,5 +1,6 @@
 use {
     crate::{it::test_error::TestResult, utils::clonecell::CloneCell},
+    isnt::std_1::collections::IsntVecDequeExt,
     std::{cell::RefCell, collections::VecDeque, rc::Rc},
 };
 
@@ -22,6 +23,13 @@ impl<T> TestExpectedEvent<T> {
             _ => bail!("No event occurred"),
         }
     }
+
+    pub fn none(&self) -> TestResult {
+        if self.data.events.borrow_mut().is_not_empty() {
+            bail!("There are unexpected events");
+        }
+        Ok(())
+    }
 }
 
 pub struct TestExpectedEventHolder<T> {