fix(declarative): ignore NO_CURSOR_STATE_KEY sentinel when reconstructing parent stream state

[devin-ai-integration]

Summary

Fixes a CDK crash at stream-construction time for manifest/low-code connectors that use a SubstreamPartitionRouter with incremental_dependency: true, where a child stream can persist the no-cursor sentinel state {"__ab_no_cursor_state_message": True} (NO_CURSOR_STATE_KEY).

ModelToComponentFactory._instantiate_parent_stream_state_manager has a fallback that reconstructs a parent stream's state from the child's state when it can't find parent_state/global_state. When the child's state dict has exactly one value, it used that value as the parent cursor value:

cursor_values = child_state.values()
if cursor_values and len(cursor_values) == 1:
    ...
    stream_state=AirbyteStateBlob({cursor_field: list(cursor_values)[0]})  # -> {cursor_field: True}

When the child previously completed with no cursor state, child_state == {"__ab_no_cursor_state_message": True}, so the fallback synthesized parent state {cursor_field: True}. Building the parent's ConcurrentCursor then calls CustomFormatConcurrentStreamStateConverter.parse_timestamp(True), which no datetime format matches, raising:

ValueError: No format in ['%Y-%m-%dT%H:%M:%S.%fZ', ...] matching True

(preceded by the warn log Trying to get_parent_state for stream ... when there are not parent state in the state).

Fix

Exclude the NO_CURSOR_STATE_KEY sentinel from the values considered by the reconstruction fallback:

cursor_values = [
    value for key, value in child_state.items() if key != NO_CURSOR_STATE_KEY
]
if cursor_values and len(cursor_values) == 1:
    ...

When the child's only state entry is the sentinel, no parent state is synthesized, so the parent cursor initializes from its configured start_datetime (equivalent to a first/empty parent sync) instead of a bogus boolean low-water-mark. This mirrors the existing sentinel handling in ConcurrentCursor.get_cursor_datetime_from_state (stream_state.get(NO_CURSOR_STATE_KEY)) and keeps real cursor state untouched.

The fix is kept at the reconstruction site (the site that produces the bad value) rather than papering over the symptom in the state-parsing layer, and does not drop or corrupt real cursor state.

Test

Added test_create_concurrent_cursor_from_perpartition_cursor_ignores_no_cursor_sentinel_child_state in unit_tests/sources/declarative/parsers/test_model_to_component_factory.py:

• Builds a declarative substream (SubstreamPartitionRouter, incremental_dependency: true) whose incoming child state is {"__ab_no_cursor_state_message": True}.
• Asserts building the stream/cursor no longer raises, and the parent cursor initializes to its configured start (2024-01-01T00:00:00.000000+0000) with no parent low-water-mark applied.
• Confirmed the test fails on current main (raises the ValueError) and passes with this change.

Also ran the existing test_model_to_component_factory.py and test_concurrent_perpartitioncursor.py suites (153 passed), plus ruff check, ruff format, and mypy — all clean.

Context

This CDK bug affects any manifest/low-code connector using substream partition routers with incremental_dependency where a child stream can persist the no-cursor sentinel; the fix and test are scoped generally rather than to a specific connector.

Triaged by Devin from oncall issue airbytehq/oncall#13077 (surfaced via source-hubspot production job 93884337). The connector manifest is correct — the defect is in the CDK.

Related to https://github.com/airbytehq/oncall/issues/13077:

• https://github.com/airbytehq/oncall/issues/13077

Link to Devin session: https://app.devin.ai/sessions/bf3e5416bb094ff3b9d896fabea7cae0

[devin-ai-integration]

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[github-actions]

PyTest Results (Fast)

4 128 tests  +1   4 116 ✅ +1   7m 36s ⏱️ -5s
    1 suites ±0      12 💤 ±0 
    1 files   ±0       0 ❌ ±0 

Results for commit 9911f40. ± Comparison against base commit dd9558c.

[github-actions]

PyTest Results (Full)

4 131 tests  +1   4 119 ✅ +1   11m 28s ⏱️ + 4m 13s
    1 suites ±0      12 💤 ±0 
    1 files   ±0       0 ❌ ±0 

Results for commit 9911f40. ± Comparison against base commit dd9558c.