chore: add repr for FrameLocator (microsoft#1018)

Author: kumaraditya303

playwright/_impl/_locator.py

@@ -503,3 +503,6 @@ def last(self) -> "FrameLocator":
 
     def nth(self, index: int) -> "FrameLocator":
         return FrameLocator(self._frame, f"{self._frame_selector} >> nth={index}")
+
+    def __repr__(self) -> str:
+        return f"<FrameLocator frame={self._frame!r} selector={self._frame_selector!r}>"

tests/sync/test_locators.py

@@ -496,6 +496,10 @@ def test_locators_frame_should_work_with_iframe(page: Page, server: Server) -> N
     button.wait_for()
     assert button.inner_text() == "Hello iframe"
     button.click()
+    assert (
+        repr(page.frame_locator("iframe"))
+        == f"<FrameLocator frame=<Frame name= url='{server.PREFIX}/empty.html'> selector='iframe'>"
+    )
 
 
 def test_locators_frame_should_work_for_nested_iframe(