Fill out remaining intersection functions

Author: mcudich

Foundation/NSOrderedSet.swift

@@ -144,8 +144,21 @@ extension NSOrderedSet {
         return false
     }
 
-    public func intersectsOrderedSet(other: NSOrderedSet) -> Bool { NSUnimplemented() }
-    public func intersectsSet(set: Set<NSObject>) -> Bool { NSUnimplemented() }
+    public func intersectsOrderedSet(other: NSOrderedSet) -> Bool {
+        if count < other.count {
+            return contains { obj in other.containsObject(obj as! NSObject) }
+        } else {
+            return other.contains { obj in containsObject(obj) }
+        }
+    }
+
+    public func intersectsSet(set: Set<NSObject>) -> Bool {
+        if count < set.count {
+            return contains { obj in set.contains(obj as! NSObject) }
+        } else {
+            return set.contains { obj in containsObject(obj) }
+        }
+    }
 
     public func isSubsetOfOrderedSet(other: NSOrderedSet) -> Bool {
         return !self.contains { obj in

TestFoundation/TestNSOrderedSet.swift

@@ -250,14 +250,19 @@ class TestNSOrderedSet : XCTestCase {
     func test_Intersection() {
         let set = NSMutableOrderedSet(arrayLiteral: "foo".bridge(), "bar".bridge(), "baz".bridge())
         let otherSet = NSOrderedSet(array: ["foo", "baz"].bridge().bridge())
+        XCTAssert(set.intersectsOrderedSet(otherSet))
         let otherOtherSet = Set(["foo".bridge(), "123".bridge()])
+        XCTAssert(set.intersectsSet(otherOtherSet))
         set.intersectOrderedSet(otherSet)
         XCTAssertEqual(set.count, 2)
         XCTAssertEqual(set[0] as? NSString, "foo")
         XCTAssertEqual(set[1] as? NSString, "baz")
         set.intersectSet(otherOtherSet)
         XCTAssertEqual(set.count, 1)
         XCTAssertEqual(set[0] as? NSString, "foo")
+
+        let nonIntersectingSet = Set(["asdf".bridge()])
+        XCTAssertFalse(set.intersectsSet(nonIntersectingSet))
     }
 
     func test_Subtraction() {