feat: handle HEAD requests

tests/test_handlers.py

@@ -36,6 +36,7 @@ class BaseHandlerTestCase(BaseTestCase, abc.ABC):
         code: int,
         message: str | None = None,
         headers: dict[str, str] | None = None,
+        content_length: int = 0,
     ) -> typing.Iterator[None]:
         if headers is None:
             headers = {}
@@ -46,7 +47,7 @@ class BaseHandlerTestCase(BaseTestCase, abc.ABC):
         send_response_mock.assert_called_once_with(code, message)
         send_header_mock.assert_has_calls(
             [
-                unittest.mock.call("Content-Length", "0"),
+                unittest.mock.call("Content-Length", str(content_length)),
             ]
             + [unittest.mock.call(header, value) for header, value in headers.items()],
             any_order=True,
@@ -192,9 +193,21 @@ class TestRequestHandler(BaseHandlerTestCase):
                 token_manager=self.token_manager,
             )
 
-    def test_do_head_forward(self) -> None:
+    def test_do_head_index(self) -> None:
         handler = self._get_handler()
         with (
+            self.expects_status_only(
+                handler, 200, content_length=len(handler.server_signature())
+            ),
+            self.patch("http.server.SimpleHTTPRequestHandler.do_HEAD", count=0),
+            self.seal_mocks(),
+        ):
+            handler.do_HEAD()
+
+    def test_do_head_forward(self) -> None:
+        handler = self._get_handler("/file")
+        with (
+            self.mock_call(self.registry.get_from_path, ["file"], Page("file")),
             self.patch("http.server.SimpleHTTPRequestHandler.do_HEAD"),
             self.seal_mocks(),
         ):