[SPARK-4866] support StructType as key in MapType

This PR brings support of using StructType(and other hashable types) as key in MapType.

Author: Davies Liu <davies@databricks.com>

Closes #3714 from davies/fix_struct_in_map and squashes the following commits:

68585d7 [Davies Liu] fix primitive types in MapType
9601534 [Davies Liu] support StructType as key in MapType

1 files changed, 8 insertions, 0 deletions

diff --git a/python/pyspark/tests.py b/python/pyspark/tests.py
index bca52a7ce6..b474fcf5bf 100644
--- a/python/pyspark/tests.py
+++ b/python/pyspark/tests.py
@@ -923,6 +923,14 @@ class SQLTests(ReusedPySparkTestCase):
         result = self.sqlCtx.sql("SELECT l[0].a from test2 where d['key'].d = '2'")
         self.assertEqual(1, result.first()[0])
 
+    def test_struct_in_map(self):
+        d = [Row(m={Row(i=1): Row(s="")})]
+        rdd = self.sc.parallelize(d)
+        srdd = self.sqlCtx.inferSchema(rdd)
+        k, v = srdd.first().m.items()[0]
+        self.assertEqual(1, k.i)
+        self.assertEqual("", v.s)
+
     def test_convert_row_to_dict(self):
         row = Row(l=[Row(a=1, b='s')], d={"key": Row(c=1.0, d="2")})
         self.assertEqual(1, row.asDict()['l'][0].a)