fix circular reference in utils and testcase module

tests/test_testcase.py

@@ -3,11 +3,86 @@ import time
 import unittest
 
 from ate import testcase
-from ate.exception import ParamsError, ApiNotFound
+from ate.exception import ApiNotFound, FileFormatError, ParamsError
 
 
 class TestcaseParserUnittest(unittest.TestCase):
 
+    def test_load_testcases_bad_filepath(self):
+        testcase_file_path = os.path.join(os.getcwd(), 'tests/data/demo')
+        self.assertEqual(testcase.load_tests(testcase_file_path), [])
+
+    def test_load_json_testcases(self):
+        testcase_file_path = os.path.join(
+            os.getcwd(), 'tests/data/demo_testset_hardcode.json')
+        testcases = testcase.load_tests(testcase_file_path)
+        self.assertEqual(len(testcases), 3)
+        test = testcases[0]["test"]
+        self.assertIn('name', test)
+        self.assertIn('request', test)
+        self.assertIn('url', test['request'])
+        self.assertIn('method', test['request'])
+
+    def test_load_yaml_testcases(self):
+        testcase_file_path = os.path.join(
+            os.getcwd(), 'tests/data/demo_testset_hardcode.yml')
+        testcases = testcase.load_tests(testcase_file_path)
+        self.assertEqual(len(testcases), 3)
+        test = testcases[0]["test"]
+        self.assertIn('name', test)
+        self.assertIn('request', test)
+        self.assertIn('url', test['request'])
+        self.assertIn('method', test['request'])
+
+    def test_load_yaml_file_file_format_error(self):
+        yaml_tmp_file = "tests/data/tmp.yml"
+        # create empty yaml file
+        with open(yaml_tmp_file, 'w') as f:
+            f.write("")
+
+        with self.assertRaises(FileFormatError):
+            testcase.load_yaml_file(yaml_tmp_file)
+
+        os.remove(yaml_tmp_file)
+
+        # create invalid format yaml file
+        with open(yaml_tmp_file, 'w') as f:
+            f.write("abc")
+
+        with self.assertRaises(FileFormatError):
+            testcase.load_yaml_file(yaml_tmp_file)
+
+        os.remove(yaml_tmp_file)
+
+    def test_load_json_file_file_format_error(self):
+        json_tmp_file = "tests/data/tmp.json"
+        # create empty file
+        with open(json_tmp_file, 'w') as f:
+            f.write("")
+
+        with self.assertRaises(FileFormatError):
+            testcase.load_json_file(json_tmp_file)
+
+        os.remove(json_tmp_file)
+
+        # create empty json file
+        with open(json_tmp_file, 'w') as f:
+            f.write("{}")
+
+        with self.assertRaises(FileFormatError):
+            testcase.load_json_file(json_tmp_file)
+
+        os.remove(json_tmp_file)
+
+        # create invalid format json file
+        with open(json_tmp_file, 'w') as f:
+            f.write("abc")
+
+        with self.assertRaises(FileFormatError):
+            testcase.load_json_file(json_tmp_file)
+
+        os.remove(json_tmp_file)
+
     def test_extract_variables(self):
         self.assertEqual(
             testcase.extract_variables("$var"),