Improve watir patch tests

spec/by_spec.rb

@@ -251,4 +251,13 @@ def by_methods
     none       = []
     expect(difference).to eq(none)
   end
+
+  it 'repeater inner errors on invalid repeaters' do
+    # Repeater constructors and setters correctly validate all input
+    # so the only way to create an invalid repeater is by direct modification
+    # of the instance variable.
+    repeater = by.repeater('ok')
+    repeater.instance_variable_set(:@repeat_descriptor, nil)
+    expect_error { repeater.process }
+  end
 end

spec/watir_patch_spec.rb

@@ -9,4 +9,31 @@
 
     expect_equal element(by.binding('slowHttpStatus')).exists?, true
   end
+
+  it 'validate_element' do
+    selector      = browser.input(id: 'testing').locator
+    locator_class = ::Watir::ElementLocator
+
+    locator = locator_class.new(browser, selector, ::Watir::Element.attribute_list)
+
+    mock_element = Class.new do
+      def tag_name
+        'input'
+      end
+
+      def attribute type
+        'random'
+      end
+    end.new
+
+    locator.validate_element mock_element
+  end
+
+  it 'watir::browser' do
+    browser.instance_variable_set(:@closed, true)
+    expect_error { browser.assert_exists }
+
+    browser.instance_variable_set(:@closed, false)
+    expect_no_error { browser.assert_exists }
+  end
 end