test: check if destination exists

.editorconfig

@@ -9,3 +9,6 @@ charset = utf-8
 [*.py]
 indent_style = space
 indent_size = 2
+
+[Makefile]
+indent_size = tab

.gitignore

@@ -1,3 +1,5 @@
 .vscode
 dist
 src/*.egg-info
+__pycache__
+.pytest_cache

Makefile

@@ -0,0 +1,7 @@
+init:
+	pip install -r requirements.txt
+
+test:
+	py.test tests
+
+.PHONY: init test

manga_up/__main__.py

@@ -3,6 +3,7 @@ Manga checker and downloader
 """
 
 import argparse
+import os
 
 if __name__ == '__main__':
   parser = argparse.ArgumentParser(
@@ -18,4 +19,11 @@ if __name__ == '__main__':
     '-n', '--notify', type=str, default=None, help="Apprise notification string."
   )
 
-args = parser.parse_args()
+  args = parser.parse_args()
+
+  destination = os.path.abspath(args.destination)
+
+  if not os.path.exists(destination):
+    print(f'Destination {destination} does not exist.')
+  if not os.path.isdir(destination):
+    print(f'Destination {destination} is not a directory.')

tests/test_arguments.py

@@ -0,0 +1,29 @@
+from subprocess import CalledProcessError
+import unittest
+import subprocess
+import os
+
+
+class ArgumentTestClass(unittest.TestCase):
+
+  def setUp(self):
+    import tempfile
+    self.existing_dir = tempfile.mkdtemp()
+
+  def test_argument_required(self):
+    with self.assertRaises(CalledProcessError):
+      subprocess.check_output(['python', 'manga_up'])
+
+  def test_destination_exists(self):
+    result = subprocess.check_output(['python', 'manga_up', '--destination', 'nonexistent'])
+    self.assertIn('does not exist', str(result))
+
+  def test_destination_is_not_directory(self):
+    result = subprocess.check_output(['python', 'manga_up', '--destination', self.existing_file])
+    self.assertIn('not a directory', str(result))
+
+  def tearDown(self) -> None:
+      os.rmdir(self.existing_dir)
+
+if __name__ == '__main__':
+  unittest.main()