Add shared AST helper usage architecture guard

Co-authored-by: Shri Sukhani <shrisukhani@users.noreply.github.com>

Author: cursoragent

CONTRIBUTING.md

@@ -87,6 +87,7 @@ This runs lint, format checks, compile checks, tests, and package build.
   - `tests/test_agent_task_read_helper_usage.py` (shared agent task read-helper usage enforcement),
   - `tests/test_agent_terminal_status_helper_usage.py` (shared agent terminal-status helper usage enforcement),
   - `tests/test_architecture_marker_usage.py` (architecture marker coverage across guard modules),
+  - `tests/test_ast_function_source_helper_usage.py` (shared AST function-source helper usage enforcement across architecture guard suites),
   - `tests/test_binary_file_open_helper_usage.py` (shared binary file open helper usage enforcement),
   - `tests/test_browser_use_payload_helper_usage.py` (browser-use payload helper usage enforcement),
   - `tests/test_ci_workflow_quality_gates.py` (CI guard-stage + make-target enforcement),

tests/test_architecture_marker_usage.py

@@ -16,6 +16,7 @@
     "tests/test_agent_task_read_helper_usage.py",
     "tests/test_agent_stop_helper_usage.py",
     "tests/test_agent_terminal_status_helper_usage.py",
+    "tests/test_ast_function_source_helper_usage.py",
     "tests/test_guardrail_ast_utils.py",
     "tests/test_helper_transport_usage_boundary.py",
     "tests/test_manager_model_dump_usage.py",

tests/test_ast_function_source_helper_usage.py

@@ -0,0 +1,30 @@
+from pathlib import Path
+
+import pytest
+
+pytestmark = pytest.mark.architecture
+
+
+AST_FUNCTION_SOURCE_GUARD_MODULES = (
+    "tests/test_job_request_route_builder_internal_reuse.py",
+    "tests/test_job_request_wrapper_internal_reuse.py",
+    "tests/test_model_request_function_transport_boundary.py",
+    "tests/test_model_request_wrapper_internal_reuse.py",
+    "tests/test_request_wrapper_internal_reuse.py",
+    "tests/test_session_recordings_follow_redirects_boundary.py",
+    "tests/test_session_request_wrapper_internal_reuse.py",
+    "tests/test_session_resource_wrapper_internal_reuse.py",
+)
+
+
+def test_ast_guard_modules_reuse_shared_collect_function_sources_helper():
+    violating_modules: list[str] = []
+    for module_path in AST_FUNCTION_SOURCE_GUARD_MODULES:
+        module_text = Path(module_path).read_text(encoding="utf-8")
+        if "ast_function_source_utils import collect_function_sources" not in module_text:
+            violating_modules.append(module_path)
+            continue
+        if "def _collect_function_sources" in module_text:
+            violating_modules.append(module_path)
+
+    assert violating_modules == []