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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: Darshan808

tests/test_tpl.py

@@ -101,13 +101,13 @@ def assert_watch_rebuilds(extension_folder):
         # Wait until the watch process is running and its initial build has
         # landed in the static directory, so that the comment below is only
         # added after watching has started.
-        wait_for(
+        assert wait_for(
             lambda: (
                 watch_process.poll() is not None
                 or list_files_in_static(static_dir) != initial_files
             ),
             timeout=WATCH_INITIAL_BUILD_TIMEOUT,
-        )
+        ), "Timed out waiting for the initial watch build to complete!"
         assert watch_process.poll() is None, "Watch process exited before the initial build!"
         files_after_initial_build = list_files_in_static(static_dir)
 
@@ -125,6 +125,11 @@ def assert_watch_rebuilds(extension_folder):
         # List filenames in static directory after change
         final_files = list_files_in_static(static_dir)
 
+        assert files_after_initial_build != final_files, (
+            "No changes detected in the static directory after modifying the source."
+            " Watch process may not have triggered correctly!"
+        )
+
         # Compare the initial and final file lists
         assert initial_files != final_files, (
             " No changes detected in the static directory."