chore: import upstream snapshot with attribution

python/ray/serve/tests/test_config_files/flaky_build.py

@@ -0,0 +1,29 @@
+"""Test fixture: raises on first FLAKY_BUILD_FAIL_COUNT imports, then succeeds.
+
+A counter file persists state across the fresh worker processes that
+``build_serve_application``'s ``max_calls=1`` decorator spawns on each retry.
+"""
+
+import os
+
+from ray import serve
+
+_COUNTER_FILE = os.environ["FLAKY_BUILD_COUNTER_FILE"]
+_FAIL_COUNT = int(os.environ.get("FLAKY_BUILD_FAIL_COUNT", "3"))
+
+with open(_COUNTER_FILE, "r") as f:
+    _attempts = int(f.read().strip() or "0")
+with open(_COUNTER_FILE, "w") as f:
+    f.write(str(_attempts + 1))
+
+if _attempts < _FAIL_COUNT:
+    raise RuntimeError(f"flaky build failure on attempt {_attempts + 1}")
+
+
+@serve.deployment
+class FlakyApp:
+    def __call__(self):
+        return "ok"
+
+
+node = FlakyApp.bind()