Fix flake8 errors

sphinx/cmd/quickstart.py

@@ -95,6 +95,12 @@ def is_path(x: str) -> str:
     return x
 
 
+def is_path_or_empty(x: str) -> str:
+    if x == '':
+        return x
+    return is_path(x)
+
+
 def allow_empty(x: str) -> str:
     return x
 
@@ -222,7 +228,10 @@ def ask_user(d: Dict) -> None:
                       'selected root path.')))
         print(__('sphinx-quickstart will not overwrite existing Sphinx projects.'))
         print()
-        sys.exit(1)
+        d['path'] = do_prompt(__('Please enter a new root path (or just Enter to exit)'),
+                              '', is_path_or_empty)
+        if not d['path']:
+            sys.exit(1)
 
     if 'sep' not in d:
         print()

tests/test_quickstart.py

@@ -123,6 +123,7 @@ def test_quickstart_defaults(tempdir):
     assert (tempdir / 'Makefile').isfile()
     assert (tempdir / 'make.bat').isfile()
 
+
 def test_quickstart_all_answers(tempdir):
     answers = {
         'Root path': tempdir,
@@ -251,12 +252,13 @@ def test_extensions(tempdir):
     exec(conffile.read_text(), ns)
     assert ns['extensions'] == ['foo', 'bar', 'baz']
 
+
 def test_exits_upon_existing_confpy(monkeypatch):
     # The code detects existing conf.py with isfile() so we mock it
     def mock_isfile(path):
         return True
     monkeypatch.setattr(path, 'isfile', mock_isfile)
-    
+
     qs.term_input = mock_input({})
     d = {}
     with pytest.raises(SystemExit):