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Mikael Goldmann commented on CRUNCH-601: ---------------------------------------- [~mkwhitacre] Thanks for taking a look at this. For the empty case, could something as ham fisted as this work (not in a place where I can easily test unfortunately)? {code} PCollection<Long> count = countTable.values() .parallelDo(new DoFn<Long, Long>() { @Override public void process(Long x, Emitter<Long> emitter) { emitter.emit(x); } @Override public void cleanup(Emitter<Long> emitter) { emitter.emit(0L); } }, Writables.longs()); return new FirstElementPObject<Long>(count); {code} > Short PCollections in SparkPipeline get length null. > ---------------------------------------------------- > > Key: CRUNCH-601 > URL: https://issues.apache.org/jira/browse/CRUNCH-601 > Project: Crunch > Issue Type: Bug > Components: Spark > Affects Versions: 0.13.0 > Environment: Running in local mode on Mac as well as in a ubuntu > 14.04 docker container > Reporter: Mikael Goldmann > Priority: Minor > Attachments: CRUNCH-601.patch, SmallCollectionLengthTest.java > > > I'll attach a file with a test that I would expect to pass but which fails. > It creates five PCollection<String> of lengths 0, 1, 2, 3, 4 gets the > lengths, runs the pipeline and prints the lengths. Finally it asserts that > all lengths are non-null. > I would expect it to print lengths 0, 1, 2, 3, 4 and pass. > What it does is print lengths null, null, null, 3, 4 and fail. > I think the underlying reason is the use of getSize() on an unmaterialized > object and assuming that when the estimate that getSize() returns is 0, then > the PCollection is guaranteed to be empty, which is false in some cases. -- This message was sent by Atlassian JIRA (v6.3.4#6332)