test: Expand test coverage to 100% on evergreen.py

Signed-off-by: Zack Koppert <[email protected]>

evergreen.py

@@ -196,7 +196,16 @@ def check_existing_config(repo, filename, update_existing):
     """
     Check if the dependabot file already exists in the
     repository and return the existing config if it does
+
+    Args:
+        repo (github3.repos.repo.Repository): The repository to check
+        filename (str): The dependabot configuration filename to check
+        update_existing (bool): Whether to update existing dependabot configuration files
+
+    Returns:
+        github3.repos.contents.Contents | None: The existing config if it exists, otherwise None
     """
+    existing_config = None
     try:
         existing_config = repo.file_contents(filename)
         if existing_config.size > 0:

test_dependabot_file.py

@@ -4,7 +4,8 @@
 from unittest.mock import MagicMock
 
 import github3
-from dependabot_file import build_dependabot_file
+import yaml
+from dependabot_file import add_existing_ecosystem_to_exempt_list, build_dependabot_file
 
 
 class TestDependabotFile(unittest.TestCase):
@@ -261,6 +262,28 @@ def test_build_dependabot_file_with_exempt_ecosystems(self):
         result = build_dependabot_file(repo, False, ["docker"], None)
         self.assertEqual(result, None)
 
+    def test_add_existing_ecosystem_to_exempt_list(self):
+        """Test that existing ecosystems are added to the exempt list"""
+        exempt_ecosystems = ["npm", "pip", "github-actions"]
+        existing_config = MagicMock()
+        existing_config.decoded = yaml.dump(
+            {
+                "updates": [
+                    {"package-ecosystem": "npm"},
+                    {"package-ecosystem": "pip"},
+                    {"package-ecosystem": "bundler"},
+                ]
+            }
+        ).encode()
+
+        add_existing_ecosystem_to_exempt_list(exempt_ecosystems, existing_config)
+
+        # Check new ecosystem is added to exempt list
+        self.assertIn("bundler", exempt_ecosystems)
+        # Keep existing ecosystems in exempt list
+        for ecosystem in exempt_ecosystems:
+            self.assertIn(ecosystem, exempt_ecosystems)
+
 
 if __name__ == "__main__":
     unittest.main()

test_evergreen.py

@@ -4,8 +4,10 @@
 import uuid
 from unittest.mock import MagicMock, patch
 
+import github3
 import requests
 from evergreen import (
+    check_existing_config,
     check_pending_issues_for_duplicates,
     check_pending_pulls_for_duplicates,
     commit_changes,
@@ -639,5 +641,51 @@ def test_is_repo_created_date_and_created_after_date_is_not_a_date(self):
             is_repo_created_date_before(repo_created_at, created_after_date)
 
 
+class TestCheckExistingConfig(unittest.TestCase):
+    """
+    Test cases for the check_existing_config function
+    """
+
+    def test_check_existing_config_with_existing_config(self):
+        """
+        Test the case where there is an existing configuration
+        """
+        mock_repo = MagicMock()
+        filename = "dependabot.yaml"
+        mock_repo.file_contents.return_value.size = 5
+
+        result = check_existing_config(mock_repo, filename, True)
+
+        self.assertIsNotNone(result)
+
+    def test_check_existing_config_without_existing_config(self):
+        """
+        Test the case where there is no existing configuration
+        """
+        mock_repo = MagicMock()
+        mock_response = MagicMock()
+        mock_repo.file_contents.side_effect = github3.exceptions.NotFoundError(
+            mock_response
+        )
+
+        result = check_existing_config(mock_repo, "dependabot.yml", True)
+
+        self.assertIsNone(result)
+
+    def test_check_existing_config_with_existing_config_without_update_existing_set(
+        self,
+    ):
+        """
+        Test the case where there is an existing configuration but UPDATE_EXISTING is False
+        """
+        mock_repo = MagicMock()
+        filename = "dependabot.yaml"
+        mock_repo.file_contents.return_value.size = 5
+
+        result = check_existing_config(mock_repo, filename, False)
+
+        self.assertIsNone(result)
+
+
 if __name__ == "__main__":
     unittest.main()