Fix url encoded credentials in netloc

Prior to this commit, it was impossible to use a module like dnf with a
URL that contains a username with an @ such as an email address
username, because:

  dnf:
    name: https://foo@example.com:bar@example.com/some.rpm

Would cause netloc parsing to fail. However, the following:

  dnf:
    name: https://foo%40example.com:bar@example.com/some.rpm

Would also fail because ansible would *not* URL-decode the credentials,
causing the following to be base64 encoded in the Authorization header:

  Zm9vJTQwZXhhbXBsZS5jb206YmFyCg==

Which decodes to:

  foo%40example.com:foo

Which is *not* the authorized username, and as such, *won't* pass basic
auth.

With this commit, Ansible's url lib behaves like curl, chromium, wget,
etc, and encodes the above to:

  Zm9vQGV4YW1wbGUuY29tOmJhcgo=

Which decodes to:

  foo@example.com:bar

Which will actually pass the HTTP Basic Auth, and is the same behaviour
that you will find ie. with:

  curl -vvI https://foo%40bar:test@example.com 2>&1 |grep Auth | awk '{ print $4 }'

changelogs/fragments/url_credentials_decode.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - support url-encoded credentials in URLs like http://x%40:%40@example.com (https://github.com/ansible/ansible/pull/82552)

lib/ansible/module_utils/urls.py

@@ -786,6 +786,8 @@ def open(self, method, url, data=None, headers=None, use_proxy=None,
                 else:
                     username = credentials
                     password = ''
+                username = unquote(username)
+                password = unquote(password)
 
                 # reconstruct url without credentials
                 url = urlunparse(parsed._replace(netloc=netloc))

test/units/module_utils/urls/test_Request.py

@@ -195,8 +195,13 @@ def test_Request_open_username(urlopen_mock, install_opener_mock):
     assert found_handlers[0].passwd.passwd[None] == {(('ansible.com', '/'),): ('user', None)}
 
 
-def test_Request_open_username_in_url(urlopen_mock, install_opener_mock):
-    r = Request().open('GET', 'http://user2@ansible.com/')
+@pytest.mark.parametrize('url, expected', (
+    ('user2@ansible.com', ('user2', '')),
+    ('user2%40@ansible.com', ('user2@', '')),
+    ('user2%40:%40@ansible.com', ('user2@', '@')),
+))
+def test_Request_open_username_in_url(url, expected, urlopen_mock, install_opener_mock):
+    r = Request().open('GET', f'http://{url}/')
 
     opener = install_opener_mock.call_args[0][0]
     handlers = opener.handlers
@@ -210,7 +215,7 @@ def test_Request_open_username_in_url(urlopen_mock, install_opener_mock):
     for handler in handlers:
         if isinstance(handler, expected_handlers):
             found_handlers.append(handler)
-    assert found_handlers[0].passwd.passwd[None] == {(('ansible.com', '/'),): ('user2', '')}
+    assert found_handlers[0].passwd.passwd[None] == {(('ansible.com', '/'),): expected}
 
 
 def test_Request_open_username_force_basic(urlopen_mock, install_opener_mock):