add test_plus_button.py

test/test_plus_button.py

@@ -0,0 +1,47 @@
+from test.test_selenium import TestSelenium
+from unittest import TestCase
+
+
+class TestPlusButton(TestSelenium, TestCase):
+    def setUp(self):
+        super(TestPlusButton, self).setUp()
+        self.plus_button = self.driver.find_element_by_id('plus-button')
+        self.minus_button = self.driver.find_element_by_id('minus-button')
+        self.selection_options_menu = self.driver.find_element_by_id(
+            'selection-options-menu')
+
+    def test_plus_button_props(self):
+        self.assertEqual(
+            self.plus_button.value_of_css_property('display'), 'block')
+        self.assertEqual(
+            self.plus_button.value_of_css_property('height'), '48px')
+        self.assertEqual(
+            self.plus_button.value_of_css_property('width'), '48px')
+        self.assertEqual(
+            self.plus_button.value_of_css_property(
+                'color'), 'rgba(68, 68, 68, 1)')
+        self.assertEqual(
+            self.plus_button.value_of_css_property(
+                'background-color'), 'rgba(204, 204, 204, 1)')
+        self.assertEqual(
+            self.selection_options_menu.value_of_css_property(
+                'display'), 'none')
+
+    def test_plus_button_before_click(self):
+        self.assertEqual(
+            self.selection_options_menu.value_of_css_property(
+                'display'), 'none')
+        self.assertEqual(
+            self.minus_button.value_of_css_property('display'), 'none')
+        self.assertEqual(
+            self.plus_button.value_of_css_property('display'), 'block')
+
+    def test_plus_button_click(self):
+        self.plus_button.click()
+        self.assertEqual(
+            self.plus_button.value_of_css_property('display'), 'none')
+        self.assertEqual(
+            self.minus_button.value_of_css_property('display'), 'block')
+        self.assertEqual(
+            self.selection_options_menu.value_of_css_property(
+                'display'), 'flex')