added first unittests

tests/test_scrape.py

@@ -0,0 +1,32 @@
+from unittest import TestCase
+from unittest.mock import patch, MagicMock, call
+
+from bs4 import BeautifulSoup
+
+from stocksymbolscraper import scrape
+
+
+class ScrapeTestCase(TestCase):
+
+    @patch.object(scrape, 'get_single_tr_data')
+    def test_extract_row_data(self, mock_get_single_tr_data: MagicMock):
+        foo = 'foo'
+        mock_get_single_tr_data.return_value = foo
+        input1, input2, input3 = MagicMock(), MagicMock(), MagicMock()
+        # Although the function expects BS4 Tag objects as arguments, we substitute with Mocks here
+        # because those arguments are immediately passed into another function, which we mock out anyway.
+        output = scrape.extract_row_data(input1, input2, input3)
+        expected_output = [foo, foo, foo]
+        self.assertListEqual(expected_output, output)
+        mock_get_single_tr_data.assert_has_calls([call(input1), call(input2), call(input3)])
+
+    def test_get_str_from_td(self):
+        expected_output = 'foo bar'
+        test_td = BeautifulSoup(f'<td>   {expected_output} </td>', 'html.parser').td
+        output = scrape.get_str_from_td(test_td)
+        self.assertEqual(expected_output, output)
+
+        expected_output = ''
+        test_td = BeautifulSoup('<td></td>', 'html.parser').td
+        output = scrape.get_str_from_td(test_td)
+        self.assertEqual(expected_output, output)