Fix docstring formatting

dev/check-integration-bug-report.md

@@ -0,0 +1,117 @@
+# Bug: `InfrahubCheckIntegrationItem.runtest` crashes with `AttributeError`
+
+A pre-existing bug in the pytest plugin's `check-integration` test kind, discovered while
+adding test coverage for the `pytest.Stash` migration in PR #985. Not introduced by that PR
+— `git log` confirms the same defect existed before the migration.
+
+## Symptom
+
+Any YAML test using `kind: check-integration` fails at runtime with:
+
+```text
+AttributeError: 'InfrahubCheckIntegrationItem' object has no attribute 'check_instance'
+```
+
+The check never executes; the GraphQL query is never issued.
+
+## Location
+
+[infrahub_sdk/pytest_plugin/items/check.py:85-94](../infrahub_sdk/pytest_plugin/items/check.py#L85-L94)
+
+```python
+class InfrahubCheckIntegrationItem(InfrahubCheckItem):
+    def runtest(self) -> None:
+        input_data = self.session.stash[INFRAHUB_CLIENT_KEY].query_gql_query(
+            self.check_instance.query,                           # <-- AttributeError here
+            variables=self.test.spec.get_variables_data(),
+        )
+        passed = self.run_check(input_data)
+
+        if not passed and self.test.expect == InfrahubTestExpectedResult.PASS:
+            raise CheckResultError(name=self.name)
+```
+
+## Root cause
+
+`self.check_instance` is declared as a type annotation in
+[InfrahubCheckItem.__init__](../infrahub_sdk/pytest_plugin/items/check.py#L34) but never
+assigned a value:
+
+```python
+class InfrahubCheckItem(InfrahubItem):
+    def __init__(self, ...) -> None:
+        super().__init__(...)
+        self.check_instance: InfrahubCheck   # annotation only, no assignment
+```
+
+The attribute is only created later, inside
+[instantiate_check](../infrahub_sdk/pytest_plugin/items/check.py#L36-L44):
+
+```python
+def instantiate_check(self) -> None:
+    ...
+    self.check_instance = check_class()
+```
+
+`InfrahubCheckSmokeItem.runtest` calls `self.instantiate_check()` as its first line, and
+`InfrahubCheckUnitProcessItem.runtest` calls it indirectly via `self.run_check()` —
+both compensate. `InfrahubCheckIntegrationItem.runtest` is the only path that reads
+`self.check_instance.query` *before* either call, so it always crashes.
+
+`run_check` does call `instantiate_check`, but only after the failing line on 88.
+
+## Why it has gone unnoticed
+
+- No unit test covers `InfrahubCheckIntegrationItem.runtest`. Coverage of
+  [check.py](../infrahub_sdk/pytest_plugin/items/check.py) is 0% in
+  `tests/unit/pytest_plugin/`.
+- Integration test kinds require a running Infrahub instance, so users hit a real
+  GraphQL endpoint to exercise this — the AttributeError surfaces before any HTTP call,
+  but the failure mode is easy to misdiagnose as "my test setup is wrong."
+- Smoke and unit-process kinds for the same resource work fine, masking the issue.
+
+## Suggested fix
+
+Call `instantiate_check()` first, mirroring `InfrahubCheckSmokeItem.runtest`:
+
+```python
+class InfrahubCheckIntegrationItem(InfrahubCheckItem):
+    def runtest(self) -> None:
+        self.instantiate_check()
+        input_data = self.session.stash[INFRAHUB_CLIENT_KEY].query_gql_query(
+            self.check_instance.query,
+            variables=self.test.spec.get_variables_data(),
+        )
+        passed = self.run_check(input_data)
+
+        if not passed and self.test.expect == InfrahubTestExpectedResult.PASS:
+            raise CheckResultError(name=self.name)
+```
+
+`run_check` will call `instantiate_check` a second time, which is wasted work but not
+incorrect — it just re-imports the check class and rebuilds the instance. If that matters,
+also drop the redundant call inside `run_check` and require all callers to instantiate
+explicitly. The other items (`InfrahubPythonTransformIntegrationItem`) already follow that
+pattern: they call `self.instantiate_transform()` at the top of `runtest`.
+
+## Reproducing
+
+A draft `test_check_integration` was written and removed from
+[tests/unit/pytest_plugin/test_plugin.py](../tests/unit/pytest_plugin/test_plugin.py)
+because there is no way to make it pass without the fix above. The reproduction shape is:
+
+1. Create a YAML test with `kind: check-integration` and a `variables: {}` spec.
+2. Create an `infrahub_config.yml` that points to a check class file.
+3. Create a check class with `query = "..."` and a `validate(data)` method.
+4. Run `pytest --infrahub-repo-config=infrahub_config.yml`.
+
+Expected: 1 passed. Actual: 1 failed with the AttributeError above.
+
+Once the fix lands, the test can be added back; the test scaffolding is straightforward
+because `httpx_mock` from the outer test scope intercepts the inner `pytester`-driven
+client (pytester runs in-process by default).
+
+## Scope
+
+This bug is out of scope for PR #985 (stash migration is a pure refactor). It should be
+fixed in a follow-up PR along with the test that covers the path.