zhengruifeng opened a new pull request, #37669:
URL: https://github.com/apache/spark/pull/37669
### What changes were proposed in this pull request?
add the validation of `num` and `numPartitions`
### Why are the changes needed?
this PR is to keep in line with the scala side
1, the scala side will check whether `num==0`
2, the scala side will check whether `numPartitions==0`, so it accept a
`emptyRDD`
```scala
scala> sc.emptyRDD[Int].takeOrdered(3)
res2: Array[Int] = Array()
```
while in PySpark:
```
In [1]: sc.emptyRDD().takeOrdered(3)
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
Input In [1], in <cell line: 1>()
----> 1 sc.emptyRDD().takeOrdered(3)
File ~/.dev/spark-3.3.0-bin-hadoop3/python/pyspark/rdd.py:1823, in
RDD.takeOrdered(self, num, key)
1820 def merge(a: List[T], b: List[T]) -> List[T]:
1821 return heapq.nsmallest(num, a + b, key)
-> 1823 return self.mapPartitions(lambda it: [heapq.nsmallest(num, it,
key)]).reduce(merge)
File ~/.dev/spark-3.3.0-bin-hadoop3/python/pyspark/rdd.py:1253, in
RDD.reduce(self, f)
1251 if vals:
1252 return reduce(f, vals)
-> 1253 raise ValueError("Can not reduce() empty RDD")
ValueError: Can not reduce() empty RDD
```
### Does this PR introduce _any_ user-facing change?
<!--
Note that it means *any* user-facing change including all aspects such as
the documentation fix.
If yes, please clarify the previous behavior and the change this PR proposes
- provide the console output, description and/or an example to show the
behavior difference if possible.
If possible, please also clarify if this is a user-facing change compared to
the released Spark versions or within the unreleased branches such as master.
If no, write 'No'.
-->
### How was this patch tested?
<!--
If tests were added, say they were added here. Please make sure to add some
test cases that check the changes thoroughly including negative and positive
cases if possible.
If it was tested in a way different from regular unit tests, please clarify
how you tested step by step, ideally copy and paste-able, so that other
reviewers can test and check, and descendants can verify in the future.
If tests were not added, please describe why they were not added and/or why
it was difficult to add.
If benchmark tests were added, please run the benchmarks in GitHub Actions
for the consistent environment, and the instructions could accord to:
https://spark.apache.org/developer-tools.html#github-workflow-benchmarks.
-->
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
