Parquet file is not partitioned Spark - scala

Question

I am trying to save a parquet Spark dataframe with partitioning to the temporary directory for unit tests, however, for some reason partitions are not created. The data itself is saved into the directory and can be used for tests.
Here is the method I have created for that:
def saveParquet(df: DataFrame, partitions: String*): String = {
val path = createTempDir()
df.repartition(1).parquet(path)(partitions: _*)
path
}
val feedPath: String = saveParquet(feedDF.select(feed.schema), "processing_time")
This method works for various dataframe with various schemas but for some reason does not generate partitions for this one. I have logged out the resulting path and it looks like this:
/var/folders/xg/fur_diuhg83b2ba15ih2rt822000dhst/T/testutils-samples8512758291/jf81n7bsj-95hs-573n-b73h-7531ug04515
But it should look like this:
/var/folders/xg/fur_diuhg83b2ba15ih2rt822000dhst/T/testutils-samples8512758291/jf81n7bsj-95hs-573n-b73h-7531ug04515/processing_time=1591714800000/part-some-random-numbersnappy.parquet
I have checked that the data and all the columns are read just fine before partitioning, as soon as partition call is created this problem occurs. Also, I ran a regex on directories which failed with match error on test samples - s".*processing_time=([0-9]+)/.*parquet".r
So what could be the reason of this problem? How else can I partition the dataframe?
Dataframe schema looks like this:
val schema: StructType = StructType(
Seq(
StructField("field1", StringType),
StructField("field2", LongType),
StructField("field3", StringType),
StructField("field4Id", IntegerType, nullable = true),
StructField("field4", FloatType, nullable = true),
StructField("field5Id", IntegerType, nullable = true),
StructField("field5", FloatType, nullable = true),
StructField("field6Id", IntegerType, nullable = true),
StructField("field6", FloatType, nullable = true),
//partition keys
StructField("processing_time", LongType)
)
)