test(mistralai): stabilize integration tests with rate limiting and retries (#37588)

Mistral integration tests have been flaky against the live API. This
adds a shared, xdist-aware rate limiter and a global retry policy so
transient 429s no longer fail the suite.

libs/partners/mistralai/Makefile

@@ -21,7 +21,7 @@ test_watch:
 
 
 integration_test integration_tests:
-	uv run --group test --group test_integration pytest -v --tb=short -n auto $(TEST_FILE)
+	uv run --group test --group test_integration pytest -v --tb=short -n auto --retries 3 --retry-delay 2 $(TEST_FILE)
 
 
 ######################

libs/partners/mistralai/pyproject.toml

@@ -44,6 +44,7 @@ Reddit = "https://www.reddit.com/r/LangChain/"
 test = [
     "pytest>=9.0.3,<10.0.0",
     "pytest-asyncio>=1.3.0,<2.0.0",
+    "pytest-retry>=1.7.0,<1.8.0",
     "pytest-watcher>=0.3.4,<1.0.0",
     "pytest-xdist>=3.6.1,<4.0.0",
     "langchain-core>=1.4.0,<2.0.0",

libs/partners/mistralai/tests/integration_tests/_rate_limiter.py

@@ -0,0 +1,18 @@
+"""Shared rate limiter for Mistral integration tests.
+
+Scaled by ``PYTEST_XDIST_WORKER_COUNT`` so aggregate QPS across all xdist
+workers stays bounded near the target rate.
+"""
+
+from __future__ import annotations
+
+import os
+
+from langchain_core.rate_limiters import InMemoryRateLimiter
+
+_TARGET_REQUESTS_PER_SECOND = 0.5
+_WORKER_COUNT = max(1, int(os.environ.get("PYTEST_XDIST_WORKER_COUNT", "1")))
+
+rate_limiter = InMemoryRateLimiter(
+    requests_per_second=_TARGET_REQUESTS_PER_SECOND / _WORKER_COUNT,
+)

libs/partners/mistralai/tests/integration_tests/test_chat_models.py

@@ -13,11 +13,12 @@ from pydantic import BaseModel
 from typing_extensions import TypedDict
 
 from langchain_mistralai.chat_models import ChatMistralAI
+from tests.integration_tests._rate_limiter import rate_limiter
 
 
 async def test_astream() -> None:
     """Test streaming tokens from ChatMistralAI."""
-    llm = ChatMistralAI()
+    llm = ChatMistralAI(rate_limiter=rate_limiter)
 
     full: BaseMessageChunk | None = None
     chunks_with_token_counts = 0
@@ -70,7 +71,7 @@ def _check_parsed_result(result: Any, schema: Any) -> None:
 
 @pytest.mark.parametrize("schema", [Book, BookDict, Book.model_json_schema()])
 def test_structured_output_json_schema(schema: Any) -> None:
-    llm = ChatMistralAI(model="ministral-8b-latest")  # type: ignore[call-arg]
+    llm = ChatMistralAI(model="ministral-8b-latest", rate_limiter=rate_limiter)  # type: ignore[call-arg]
     structured_llm = llm.with_structured_output(schema, method="json_schema")
 
     messages = [
@@ -91,7 +92,7 @@ def test_structured_output_json_schema(schema: Any) -> None:
 
 @pytest.mark.parametrize("schema", [Book, BookDict, Book.model_json_schema()])
 async def test_structured_output_json_schema_async(schema: Any) -> None:
-    llm = ChatMistralAI(model="ministral-8b-latest")  # type: ignore[call-arg]
+    llm = ChatMistralAI(model="ministral-8b-latest", rate_limiter=rate_limiter)  # type: ignore[call-arg]
     structured_llm = llm.with_structured_output(schema, method="json_schema")
 
     messages = [
@@ -116,6 +117,7 @@ def test_retry_parameters(caplog: pytest.LogCaptureFixture) -> None:
     mistral = ChatMistralAI(
         timeout=1,  # Very short timeout to trigger timeouts
         max_retries=3,  # Should retry 3 times
+        rate_limiter=rate_limiter,
     )
 
     # Simple test input that should take longer than 1 second to process
@@ -148,7 +150,7 @@ def test_retry_parameters(caplog: pytest.LogCaptureFixture) -> None:
 
 
 def test_reasoning() -> None:
-    model = ChatMistralAI(model="magistral-medium-latest")  # type: ignore[call-arg]
+    model = ChatMistralAI(model="magistral-medium-latest", rate_limiter=rate_limiter)  # type: ignore[call-arg]
     input_message = {
         "role": "user",
         "content": "Hello, my name is Bob.",
@@ -172,7 +174,11 @@ def test_reasoning() -> None:
 
 
 def test_reasoning_v1() -> None:
-    model = ChatMistralAI(model="magistral-medium-latest", output_version="v1")  # type: ignore[call-arg]
+    model = ChatMistralAI(  # type: ignore[call-arg]
+        model="magistral-medium-latest",
+        output_version="v1",
+        rate_limiter=rate_limiter,
+    )
     input_message = {
         "role": "user",
         "content": "Hello, my name is Bob.",

libs/partners/mistralai/tests/integration_tests/test_standard.py

@@ -7,6 +7,7 @@ from langchain_tests.integration_tests import (  # type: ignore[import-not-found
 )
 
 from langchain_mistralai import ChatMistralAI
+from tests.integration_tests._rate_limiter import rate_limiter
 
 
 class TestMistralStandard(ChatModelIntegrationTests):
@@ -16,7 +17,11 @@ class TestMistralStandard(ChatModelIntegrationTests):
 
     @property
     def chat_model_params(self) -> dict:
-        return {"model": "mistral-large-latest", "temperature": 0}
+        return {
+            "model": "mistral-large-latest",
+            "temperature": 0,
+            "rate_limiter": rate_limiter,
+        }
 
     @property
     def supports_json_mode(self) -> bool:

libs/partners/mistralai/uv.lock

@@ -454,6 +454,7 @@ test = [
     { name = "langchain-tests" },
     { name = "pytest" },
     { name = "pytest-asyncio" },
+    { name = "pytest-retry" },
     { name = "pytest-watcher" },
     { name = "pytest-xdist" },
 ]
@@ -479,6 +480,7 @@ test = [
     { name = "langchain-tests", editable = "../../standard-tests" },
     { name = "pytest", specifier = ">=9.0.3,<10.0.0" },
     { name = "pytest-asyncio", specifier = ">=1.3.0,<2.0.0" },
+    { name = "pytest-retry", specifier = ">=1.7.0,<1.8.0" },
     { name = "pytest-watcher", specifier = ">=0.3.4,<1.0.0" },
     { name = "pytest-xdist", specifier = ">=3.6.1,<4.0.0" },
 ]
@@ -1137,6 +1139,18 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/42/c2/ce34735972cc42d912173e79f200fe66530225190c06655c5632a9d88f1e/pytest_recording-0.13.4-py3-none-any.whl", hash = "sha256:ad49a434b51b1c4f78e85b1e6b74fdcc2a0a581ca16e52c798c6ace971f7f439", size = 13723, upload-time = "2025-05-08T10:41:09.684Z" },
 ]
 
+[[package]]
+name = "pytest-retry"
+version = "1.7.0"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "pytest" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/c5/5b/607b017994cca28de3a1ad22a3eee8418e5d428dcd8ec25b26b18e995a73/pytest_retry-1.7.0.tar.gz", hash = "sha256:f8d52339f01e949df47c11ba9ee8d5b362f5824dff580d3870ec9ae0057df80f", size = 19977, upload-time = "2025-01-19T01:56:13.115Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/7c/ff/3266c8a73b9b93c4b14160a7e2b31d1e1088e28ed29f4c2d93ae34093bfd/pytest_retry-1.7.0-py3-none-any.whl", hash = "sha256:a2dac85b79a4e2375943f1429479c65beb6c69553e7dae6b8332be47a60954f4", size = 13775, upload-time = "2025-01-19T01:56:11.199Z" },
+]
+
 [[package]]
 name = "pytest-socket"
 version = "0.7.0"