kaxil opened a new pull request, #73959:
URL: https://github.com/apache/airflow/pull/73959

   A short-circuit task inside a mapped task group stopped skipping the task 
after it in 3.2.0.
   
   Each map index of a task in a mapped task group runs as its own task 
instance, so `SkipMixin` writes the skip decision to XCom under that map index. 
#62287 changed `NotPreviouslySkippedDep` to read that XCom at `map_index=-1` 
unless the parent is a `MappedOperator`, to fix an unmapped 
`LatestOnlyOperator` upstream of a mapped task. A task inside a mapped task 
group is a plain operator whose `is_mapped` is False, so the dep read `-1`, 
found no decision, and let the downstream task run.
   
   The dep now checks `get_needs_expansion()`, which is true for a mapped 
operator and for any task inside a mapped task group: the tasks that write XCom 
per map index. An unmapped parent still reads `-1`, and the regression test 
from #62287 passes unchanged.
   
   A gate that returns False for odd map indexes, `gate(v) >> printstr(v)` 
inside a task group expanded over `[0, 1, 2, 3]`, run by the scheduler before 
and after the change:
   
   ![Before: group_1.printstr runs for every map 
index](./mapped-group-before.png)
   
   ![After: group_1.printstr is skipped for map indexes 1 and 
3](./mapped-group-after.png)
   
   related: #55225
   
   ---
   
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