mirror of
https://github.com/pydantic/pydantic-ai-harness.git
synced 2026-07-21 10:55:35 +00:00
David SFandGitHub
6c60f7cf0d
* feat(step_persistence): rescue last provider-valid resume point on error `StepPersistence` previously left an errored run with no `ContinuableSnapshot` for a provider-valid state that no node boundary had captured, so `continue_run` could only resume from an earlier point or raise `LookupError`. Add an error-path capture: when a run fails against a provider-valid history, save one snapshot so the run still exposes its last safe resume point. Two sites cover the two ways such a state is reached without a completed-node snapshot: - `on_model_request_error` saves the request payload directly -- e.g. a resolved tool cycle, which is only provider-valid as the next request is built, never at a `CallToolsNode` boundary. - `on_run_error` reads a `latest_node_history` contextvar refreshed at every `after_node_run` boundary, rescuing a text response whose following `CallToolsNode` raises inside output validation. It cannot read `ctx.messages` directly: the `RunContext` passed to `on_run_error` holds the start-of-run history, which the graph rebinds away during the run. Both saves are gated on `_is_resumable_history` (provider-valid plus at least one `ModelResponse`), so a crash mid-tool-call leaves a dangling `ToolCallPart` that is skipped and `latest_snapshot` never regresses to an unsendable point. `on_run_error` compares by message count and skips when the store already holds a newer snapshot, so a stale completed-node stash never supersedes a fresher `on_model_request_error` save. This is the gated (provider-validity) approach; the ungated simplification that rides on pydantic-ai#6319 is deferred to a follow-up. Closes #253 * test(step_persistence): drop dead validator branch to restore 100% coverage The `gate` output-validator in `test_does_not_regress_to_stale_stash_after_model_request_save` had a `return value` branch that never executed: the run fails on request 3 before any output passes validation a second time. Simplify it to always raise `ModelRetry` (one retry is all the stash scenario needs), matching the sibling `test_rescues_newest_text_history_over_earlier_saved_snapshot`.