[SPARK-10373] [PYSPARK] move @since into pyspark from sql

cc mengxr

Author: Davies Liu <davies@databricks.com>

Closes #8657 from davies/move_since.

1 files changed, 16 insertions, 0 deletions

diff --git a/python/pyspark/__init__.py b/python/pyspark/__init__.py
index 5f70ac6ed8..8475dfb1c6 100644
--- a/python/pyspark/__init__.py
+++ b/python/pyspark/__init__.py
@@ -48,6 +48,22 @@ from pyspark.serializers import MarshalSerializer, PickleSerializer
 from pyspark.status import *
 from pyspark.profiler import Profiler, BasicProfiler
 
+
+def since(version):
+    """
+    A decorator that annotates a function to append the version of Spark the function was added.
+    """
+    import re
+    indent_p = re.compile(r'\n( +)')
+
+    def deco(f):
+        indents = indent_p.findall(f.__doc__)
+        indent = ' ' * (min(len(m) for m in indents) if indents else 0)
+        f.__doc__ = f.__doc__.rstrip() + "\n\n%s.. versionadded:: %s" % (indent, version)
+        return f
+    return deco
+
+
 # for back compatibility
 from pyspark.sql import SQLContext, HiveContext, SchemaRDD, Row