Get log.capnp from target branch

selfdrive/test/process_replay/test_log_compat.py

@@ -1,21 +1,38 @@
 import os
 import capnp
+import pytest
+import shutil
 import hypothesis.strategies as st
 from hypothesis import given, settings, HealthCheck
 
+from cereal import CEREAL_PATH
 from openpilot.selfdrive.test.fuzzy_generation import FuzzyGenerator
 from openpilot.tools.lib.logreader import LogReader
+from openpilot.common.run import run_cmd
 
 MAX_EXAMPLES = int(os.environ.get("MAX_EXAMPLES", "10"))
+TARGET_REMOTE = os.environ.get("TARGET_REMOTE", "origin")
+TARGET_BRANCH = os.environ.get("TARGET_BRANCH", "master")
+
+
+@pytest.fixture(scope="module")
+def parent_schema_file(tmp_path_factory):
+  commit = run_cmd(["git", "merge-base", f"{TARGET_REMOTE}/{TARGET_BRANCH}", "HEAD"])
+  log_capnp_url = f"https://raw.githubusercontent.com/commaai/openpilot/{commit}/cereal/log.capnp"
+  tmp_dir = tmp_path_factory.mktemp("capnp")
+  tmp_log_capnp_path = tmp_dir / f"{commit}-log.capnp"
+  if not tmp_log_capnp_path.exists():
+    run_cmd(["curl", "-o", str(tmp_log_capnp_path), log_capnp_url])
+
+  return str(tmp_log_capnp_path)
 
 
 @given(st.data())
 @settings(max_examples=MAX_EXAMPLES, suppress_health_check=[HealthCheck.large_base_example])
-def test_log_backwards_compatibility(schema_path, data):
+def test_log_backwards_compatibility(parent_schema_file, data):
   # capnp global parser needs to be cleaned up to avoid schema/struct ID conflicts
-  capnp.cleanup_global_schema_parser()
-  old_log = capnp.load(schema_path)
-  capnp.cleanup_global_schema_parser()
+  capnp_parser = capnp.SchemaParser()
+  old_log = capnp_parser.load(parent_schema_file, imports=[CEREAL_PATH])
 
   msgs_dicts = FuzzyGenerator.get_random_event_msg(data.draw, log_schema=old_log, events=old_log.Event.schema.union_fields, real_floats=True)
   msgs = [old_log.Event.new_message(**m).as_reader() for m in msgs_dicts]