SPARK-1757 Failing test for saving null primitives with .saveAsParquetFile()

[ash211]

https://issues.apache.org/jira/browse/SPARK-1757

The first test succeeds, but the second test fails with exception:

[info] - save and load case class RDD with Nones as parquet *** FAILED *** (14 milliseconds)
[info] java.lang.RuntimeException: Unsupported datatype StructType(List())
[info] at scala.sys.package$.error(package.scala:27)
[info] at org.apache.spark.sql.parquet.ParquetTypesConverter$.fromDataType(ParquetRelation.scala:201)
[info] at org.apache.spark.sql.parquet.ParquetTypesConverter$$anonfun$1.apply(ParquetRelation.scala:235)
[info] at org.apache.spark.sql.parquet.ParquetTypesConverter$$anonfun$1.apply(ParquetRelation.scala:235)
[info] at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
[info] at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
[info] at scala.collection.immutable.List.foreach(List.scala:318)
[info] at scala.collection.TraversableLike$class.map(TraversableLike.scala:244)
[info] at scala.collection.AbstractTraversable.map(Traversable.scala:105)
[info] at org.apache.spark.sql.parquet.ParquetTypesConverter$.convertFromAttributes(ParquetRelation.scala:234)
[info] at org.apache.spark.sql.parquet.ParquetTypesConverter$.writeMetaData(ParquetRelation.scala:267)
[info] at org.apache.spark.sql.parquet.ParquetRelation$.createEmpty(ParquetRelation.scala:143)
[info] at org.apache.spark.sql.parquet.ParquetRelation$.create(ParquetRelation.scala:122)
[info] at org.apache.spark.sql.execution.SparkStrategies$ParquetOperations$.apply(SparkStrategies.scala:139)
[info] at org.apache.spark.sql.catalyst.planning.QueryPlanner$$anonfun$1.apply(QueryPlanner.scala:58)
[info] at org.apache.spark.sql.catalyst.planning.QueryPlanner$$anonfun$1.apply(QueryPlanner.scala:58)
[info] at scala.collection.Iterator$$anon$13.hasNext(Iterator.scala:371)
[info] at org.apache.spark.sql.catalyst.planning.QueryPlanner.apply(QueryPlanner.scala:59)
[info] at org.apache.spark.sql.SQLContext$QueryExecution.sparkPlan$lzycompute(SQLContext.scala:264)
[info] at org.apache.spark.sql.SQLContext$QueryExecution.sparkPlan(SQLContext.scala:264)
[info] at org.apache.spark.sql.SQLContext$QueryExecution.executedPlan$lzycompute(SQLContext.scala:265)
[info] at org.apache.spark.sql.SQLContext$QueryExecution.executedPlan(SQLContext.scala:265)
[info] at org.apache.spark.sql.SQLContext$QueryExecution.toRdd$lzycompute(SQLContext.scala:268)
[info] at org.apache.spark.sql.SQLContext$QueryExecution.toRdd(SQLContext.scala:268)
[info] at org.apache.spark.sql.SchemaRDDLike$class.saveAsParquetFile(SchemaRDDLike.scala:66)
[info] at org.apache.spark.sql.SchemaRDD.saveAsParquetFile(SchemaRDD.scala:98)

[ash211]

/cc: @marmbrus

[AmplabJenkins]

Merged build triggered.

[AmplabJenkins]

Merged build started.

[marmbrus]

We are incorrectly detecting the Options as repeated types (Seq), which are not supported in parquet yet.

Fix here

[AmplabJenkins]

Merged build finished.

[AmplabJenkins]

Refer to this link for build results: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/14807/

[AmplabJenkins]

Merged build triggered.

[AmplabJenkins]

Merged build started.

[ash211]

Michael's fix looks good and the test passes now, so unless there's an overhaul of this technique coming soon it probably makes sense to merge this in (pre-1.0).

[AmplabJenkins]

Merged build finished. All automated tests passed.

[AmplabJenkins]

All automated tests passed.
Refer to this link for build results: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/14810/

[rxin]

Merging this. Thanks!