From 53dd1798a6022d5b523f2303c3a96f5b86115d25 Mon Sep 17 00:00:00 2001
From: Valdir Stumm Junior <stummjr@gmail.com>
Date: Sun, 20 Nov 2016 21:27:49 -0200
Subject: [PATCH] add implementation for set.intersection()

---
 python/common/org/python/types/Set.java | 7 +++++--
 tests/datatypes/test_set.py             | 8 +++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/python/common/org/python/types/Set.java b/python/common/org/python/types/Set.java
index df39e6f04f..76aad71876 100644
--- a/python/common/org/python/types/Set.java
+++ b/python/common/org/python/types/Set.java
@@ -380,10 +380,13 @@ public org.python.Object __iadd__(org.python.Object other) {
     }
 
     @org.python.Method(
-        __doc__ = ""
+        __doc__ = "Return the intersection of two sets as a new set.\n\n(i.e. all elements that are in both sets.)",
+        args = {"other"}
     )
     public org.python.Object intersection(org.python.Object other) {
-        throw new org.python.exceptions.NotImplementedError("intersection() has not been implemented.");
+        java.util.Set set = ((Set) this.copy()).value;
+        set.retainAll(((Set) other).value);
+        return new Set(set);
     }
 
     @org.python.Method(
diff --git a/tests/datatypes/test_set.py b/tests/datatypes/test_set.py
index 1de30c5995..07af39d71a 100644
--- a/tests/datatypes/test_set.py
+++ b/tests/datatypes/test_set.py
@@ -100,7 +100,13 @@ def test_discard(self):
             print(x)
             """)
 
-
+    def test_intersection(self):
+        self.assertCodeExecution("""
+            x = {1, 2, 3}
+            y = {3, 4, 5}
+            z = x.intersection(y)
+            print(z)
+            """)
 
 
 class UnarySetOperationTests(UnaryOperationTestCase, TranspileTestCase):