@Test
	public void testSetText() {

		setText("d");

		JWindow matchingWindow = textField.getActiveMatchingWindow();

		// make sure our set text call did not trigger the window to be created
		assertNull(
			"The completion window has been created before any completion work " + "has began.",
			matchingWindow);

		clearText();
		typeText("d", true);

		// one more time
		clearText();
		setText("c");

		// make sure our set text call did not trigger the window to be created
		matchingWindow = textField.getActiveMatchingWindow();
		assertNull("The completion window has been created before any completion work has started",
			matchingWindow);
	}
This test achieves partial coverage of {@link DropDownTextField}.  Further coverage is
provided by {@link DropDownSelectionTextFieldTest}, as that test enables item selection 
in the widget being tested.
Ghidra/Framework/Docking/src/test/java/docking/widgets/DropDownTextFieldTest.java