Test that we can output a valid test directory.

tests/data/nest/less/why.md

@@ -0,0 +1,11 @@
+# why?
+
+Tests need to work even when the same filename is in multiple directories.
+
+```py
+import unittest
+
+class TestLess(unittest.TestCase):
+    def test_less(self):
+        self.assertTrue(True)
+```

tests/data/nest/more/why.md

@@ -3,7 +3,11 @@
 We want to make sure that in more complext documentation structures, which may have multiple sub directories, we are still formatting name and paths correctly.
 
 ```py
-print("oh that makes sense")
+import unittest
+
+class TestMore(unittest.TestCase):
+    def test_more(self):
+        self.assertTrue(True)
 ```
 
 Good.

tests/test.py

@@ -2,6 +2,7 @@
 import shutil
 import textwrap
 import unittest
+import subprocess
 
 import click.testing
 
@@ -130,6 +131,14 @@ def test_prefixed_deep_blocks(self):
         self.assertTrue(self._output_path_exists('test_other.py'))
         self.assertTrue(self._output_path_exists('nest/test_deep.py'))
         self.assertTrue(self._output_path_exists('nest/more/test_why.py'))
+        self.assertTrue(self._output_path_exists('nest/less/test_why.py'))
+
+        # Check that mkcodes can actually output a valid test directory.
+        proc = subprocess.run(
+            ['python3', '-m', 'unittest', 'discover', 'tests/output'],
+            capture_output=True, text=True)
+        self.assertIn('Ran 2 tests', proc.stderr)
+        self.assertIn('OK', proc.stderr)
 
     @unittest.skip
     def test_glob(self):