The thread stream's lifecycle watcher ended the run on any `completed`
or `failed` lifecycle event, including the one a subgraph sends when it
finishes. So `thread.output` could read the thread state before the
parent stored the step that ran the subgraph, and a run that failed
after a subgraph completed was reported as completed. The async and sync
watchers now end the run only on a root event, with the
`_is_root_terminal_lifecycle` check the fanout already uses. The JS SDK
checks the root namespace here too.
This is the `sdk-py integration` flake where the final `items` comes
back as `['streamed', 'tool', 'asked']` without `'sub'`: the example
graph's last node runs a subgraph.
## Tests
New async and sync tests send a subgraph `completed` and then a root
`failed`. Without the fix the run ends as completed. `make lint` and
`make test` in `libs/sdk-py` pass.
Follow-up to #8540, which turned on `PLC0415` (import-outside-top-level)
for checkpoint-postgres and checkpoint-sqlite. This does the remaining
six packages: checkpoint, checkpoint-conformance, langgraph, prebuilt,
cli, sdk-py.
Scoped to tests, per @sydney-runkle's call on #8540: library code is
exempted with `per-file-ignores`, since it still has deferred imports
nobody has reviewed and mixing that in would make this hard to read.
## What changed
Function-level imports across 56 test files moved to module level. Nine
could not move and carry an explicit `# noqa: PLC0415` with a reason:
| File | Why it stays local |
|---|---|
| `libs/langgraph/tests/test_deprecation.py` (4) | the import has to run
inside `pytest.warns` for the warning to be observed |
| `libs/langgraph/tests/test_serde_allowlist.py` | try/except guard,
skips when langchain_core is absent |
| `libs/langgraph/tests/test_delta_channel_benchmark.py` | optional
psycopg probe |
| `libs/checkpoint/tests/test_conformance_delta.py` (3) | protected by a
module-level `pytest.importorskip`; hoisting past the guard turns a skip
into a collection error |
That last one is the trap: an import moved above `pytest.importorskip`
silently defeats the guard. I hit it locally and it turned the skip into
a `ModuleNotFoundError` at collection. Every file with an `importorskip`
or `except ImportError` was checked by hand for this.
## Verification
`make lint` and `make test` in each of the six:
| Package | Tests |
|---|---|
| checkpoint | 156 passed, 17 skipped |
| checkpoint-conformance | 1 passed |
| langgraph | 1968 passed, 4 skipped |
| prebuilt | 284 passed |
| cli | 336 passed |
| sdk-py | 493 passed |
Also confirmed the rule actually fires: a throwaway test file with a
function-level import is flagged in all six packages, and the source
exemption holds.
