Keep a renamed anyio helper from breaking every test run

.github/workflows/ci.yml

@@ -84,6 +84,29 @@ jobs:
       - name: Run tests
         run: uv run --no-sync pytest tests
 
+  upstream:
+    name: Run unit tests on anyio main
+    runs-on: ubuntu-latest
+    # The pytest plugin uses two helpers `anyio` keeps out of its public API,
+    # and it loads in every test run of everyone who installs `anydi`.
+    continue-on-error: true
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v5
+        with:
+          python-version: '3.12'
+          enable-cache: true
+      - name: Install dependencies
+        run: uv sync --all-extras --dev
+      - name: Take anyio from main
+        run: uv pip install --upgrade "anyio @ git+https://github.com/agronholm/anyio"
+      - name: Run tests
+        run: |
+          uv run --no-sync pytest tests
+          uv run --no-sync pytest tests/ext/test_pytest_plugin.py -p anydi
+
   benchmarks:
     name: Run benchmarks
     runs-on: ubuntu-latest

anydi/ext/pytest_plugin.py

@@ -7,7 +7,6 @@
 from typing import TYPE_CHECKING, Annotated, Any, cast, get_args, get_origin
 
 import pytest
-from anyio.pytest_plugin import extract_backend_and_options, get_runner
 from typing_extensions import get_annotations
 
 from anydi import (
@@ -121,6 +120,19 @@ async def _resolve() -> None:
                     "Failed to resolve '%s' for %s", name, request.node.nodeid
                 )
 
+    # `anyio` keeps these out of its public API, so a version that renames them
+    # breaks async injection only, not every test run that imports this plugin.
+    try:
+        from anyio.pytest_plugin import extract_backend_and_options, get_runner
+    except ImportError:  # pragma: no cover - a version that moved them
+        pytest.fail(
+            "Injecting dependencies into async tests needs "  # ty: ignore[invalid-argument-type]
+            "`extract_backend_and_options` and `get_runner` from "
+            "`anyio.pytest_plugin`, which this version of `anyio` does not "
+            "have. Resolve the dependency in the test instead, or report it.",
+            pytrace=False,  # ty: ignore[parameter-already-assigned]
+        )
+
     anyio_backend = request.getfixturevalue("anyio_backend")
     backend_name, backend_options = extract_backend_and_options(anyio_backend)