diff --git a/python/servo/devtools_tests.py b/python/servo/devtools_tests.py
index 8b3ebf0dbb9..3cab7a45991 100644
--- a/python/servo/devtools_tests.py
+++ b/python/servo/devtools_tests.py
@@ -141,6 +141,23 @@ class DevtoolsTests(unittest.IsolatedAsyncioTestCase):
expected_content = open(self.get_test_path("sources_content_with_responsexml/test.html")).read()
self.assert_source_content(f"{self.base_url}/test.html", expected_content)
+ def test_source_breakable_lines_and_positions(self):
+ self.start_web_server(test_dir=self.get_test_path("sources_breakable_lines_and_positions"))
+ self.run_servoshell()
+ self.assert_source_breakable_lines_and_positions(
+ f"{self.base_url}/test.html",
+ list(range(1, 8)),
+ {
+ "1": list(range(15)),
+ "2": list(range(22)),
+ "3": list(range(8)),
+ "4": list(range(35)),
+ "5": list(range(46)), # includes 3 surrogate pairs
+ "6": list(range(46)), # includes 1 surrogate pair
+ "7": list(range(9)),
+ },
+ )
+
# Sets `base_url` and `web_server` and `web_server_thread`.
def start_web_server(self, *, test_dir=None):
if test_dir is None:
@@ -305,6 +322,49 @@ class DevtoolsTests(unittest.IsolatedAsyncioTestCase):
client.disconnect()
+ def assert_source_breakable_lines_and_positions(
+ self, source_url: str, expected_breakable_lines: list[int], expected_positions: dict[int, list[int]]
+ ):
+ client, watcher, targets = self._setup_devtools_client()
+
+ done = Future()
+ source_actors = {}
+
+ def on_source_resource(data):
+ for [resource_type, sources] in data["array"]:
+ try:
+ self.assertEqual(resource_type, "source")
+ for source in sources:
+ if source["url"] == source_url:
+ source_actors[source_url] = source["actor"]
+ done.set_result(None)
+ except Exception as e:
+ done.set_result(e)
+
+ for target in targets:
+ client.add_event_listener(
+ target["actor"],
+ Events.Watcher.RESOURCES_AVAILABLE_ARRAY,
+ on_source_resource,
+ )
+ watcher.watch_resources([Resources.SOURCE])
+
+ result: Optional[Exception] = done.result(1)
+ if result:
+ raise result
+
+ # We found at least one source with the given url.
+ self.assertIn(source_url, source_actors)
+ source_actor = source_actors[source_url]
+
+ response = client.send_receive({"to": source_actor, "type": "getBreakableLines"})
+ self.assertEqual(response["lines"], expected_breakable_lines)
+
+ response = client.send_receive({"to": source_actor, "type": "getBreakpointPositionsCompressed"})
+ self.assertEqual(response["positions"], expected_positions)
+
+ client.disconnect()
+
def get_test_path(self, path: str) -> str:
return os.path.join(DevtoolsTests.script_path, os.path.join("devtools_tests", path))
diff --git a/python/servo/devtools_tests/sources_breakable_lines_and_positions/test.html b/python/servo/devtools_tests/sources_breakable_lines_and_positions/test.html
new file mode 100644
index 00000000000..810fbafa368
--- /dev/null
+++ b/python/servo/devtools_tests/sources_breakable_lines_and_positions/test.html
@@ -0,0 +1,7 @@
+
+
+