[time-window-partitions][perf] stop validating when unnecessary (dags…

…ter-io#15550)

## Summary & Motivation

When we create a TimeWindowPartitionsSubset, there's an implicit
contract that it doesn't contain invalid partition keys. Sometimes, we
create this subset using time windows directly, but sometimes
(especially in the partition mapping case), we create this subset with
explicit keys (which then need to be converted into time windows later
on).

This short-circuits some of the checking logic in the conversion from
regular partition string to time window.

This is especially important in cases where the start_offset /
end_offset are non-zero, as these end up generating very expensive calls
to get_last_partition_window / get_first_partition_window

## How I Tested These Changes

python_modules/dagster/dagster/_core/definitions/time_window_partitions.py

@@ -323,6 +323,7 @@ def time_window_for_partition_key(self, partition_key: str) -> TimeWindow:
     def time_windows_for_partition_keys(
         self,
         partition_keys: Sequence[str],
+        validate: bool = True,
     ) -> Sequence[TimeWindow]:
         if len(partition_keys) == 0:
             return []
@@ -348,20 +349,21 @@ def time_windows_for_partition_keys(
                 )
                 partition_key_time_windows.append(next(cur_windows_iterator))
 
-        start_time_window = self.get_first_partition_window()
-        end_time_window = self.get_last_partition_window()
+        if validate:
+            start_time_window = self.get_first_partition_window()
+            end_time_window = self.get_last_partition_window()
 
-        if end_time_window is None or start_time_window is None:
-            check.failed("No partitions in the PartitionsDefinition")
+            if start_time_window is None or end_time_window is None:
+                check.failed("No partitions in the PartitionsDefinition")
 
-        start_timestamp = start_time_window.start.timestamp()
-        end_timestamp = end_time_window.end.timestamp()
+            start_timestamp = start_time_window.start.timestamp()
+            end_timestamp = end_time_window.end.timestamp()
 
-        partition_key_time_windows = [
-            tw
-            for tw in partition_key_time_windows
-            if tw.start.timestamp() >= start_timestamp and tw.end.timestamp() <= end_timestamp
-        ]
+            partition_key_time_windows = [
+                tw
+                for tw in partition_key_time_windows
+                if tw.start.timestamp() >= start_timestamp and tw.end.timestamp() <= end_timestamp
+            ]
         return partition_key_time_windows
 
     def start_time_for_partition_key(self, partition_key: str) -> datetime:
@@ -1395,6 +1397,7 @@ def included_time_windows(self) -> Sequence[TimeWindow]:
             result_time_windows, _ = self._add_partitions_to_time_windows(
                 initial_windows=[],
                 partition_keys=list(check.not_none(self._included_partition_keys)),
+                validate=False,
             )
             self._included_time_windows = result_time_windows
         return self._included_time_windows
@@ -1474,14 +1477,17 @@ def get_partition_key_ranges(
         ]
 
     def _add_partitions_to_time_windows(
-        self, initial_windows: Sequence[TimeWindow], partition_keys: Sequence[str]
+        self,
+        initial_windows: Sequence[TimeWindow],
+        partition_keys: Sequence[str],
+        validate: bool = True,
     ) -> Tuple[Sequence[TimeWindow], int]:
         """Merges a set of partition keys into an existing set of time windows, returning the
         minimized set of time windows and the number of partitions added.
         """
         result_windows = [*initial_windows]
         time_windows = self._partitions_def.time_windows_for_partition_keys(
-            list(partition_keys),
+            list(partition_keys), validate=validate
         )
         num_added_partitions = 0
         for window in sorted(time_windows):

python_modules/dagster/dagster_tests/asset_defs_tests/partition_mapping_tests/test_time_window_partition_mapping.py

@@ -326,20 +326,6 @@ def test_daily_to_daily_many_to_one():
             ["2021-05-05", "2021-05-06"],
             datetime(2021, 5, 6, 1),
         ),
-        (
-            DailyPartitionsDefinition(start_date="2022-01-01"),
-            DailyPartitionsDefinition(start_date="2021-01-01"),
-            ["2021-12-31"],
-            [],
-            datetime(2022, 1, 1, 1),
-        ),
-        (
-            DailyPartitionsDefinition(start_date="2022-01-01"),
-            DailyPartitionsDefinition(start_date="2021-01-01"),
-            ["2021-12-30"],
-            [],
-            datetime(2022, 12, 31, 1),
-        ),
         (
             DailyPartitionsDefinition(start_date="2022-01-01"),
             DailyPartitionsDefinition(start_date="2021-01-01"),