added some empty, min, and max to RangedSet

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@816221 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 46 insertions, 0 deletions

diff --git a/qpid/python/qpid/datatypes.py b/qpid/python/qpid/datatypes.py
index f832ddae34..61643715e4 100644
--- a/qpid/python/qpid/datatypes.py
+++ b/qpid/python/qpid/datatypes.py
@@ -234,6 +234,24 @@ class RangedSet:
   def add(self, lower, upper = None):
     self.add_range(Range(lower, upper))
 
+  def empty(self):
+    for r in self.ranges:
+      if r.lower <= r.upper:
+        return False
+    return True
+
+  def max(self):
+    if self.ranges:
+      return self.ranges[-1].upper
+    else:
+      return None
+
+  def min(self):
+    if self.ranges:
+      return self.ranges[0].lower
+    else:
+      return None
+
   def __iter__(self):
     return iter(self.ranges)
 
diff --git a/qpid/python/tests/datatypes.py b/qpid/python/tests/datatypes.py
index b00e5e78f8..00e649d6cf 100644
--- a/qpid/python/tests/datatypes.py
+++ b/qpid/python/tests/datatypes.py
@@ -148,6 +148,34 @@ class RangedSetTest(TestCase):
     assert range.lower == 0
     assert range.upper == 8
 
+  def testEmpty(self):
+    s = RangedSet()
+    assert s.empty()
+    s.add(0, -1)
+    assert s.empty()
+    s.add(0, 0)
+    assert not s.empty()
+
+  def testMinMax(self):
+    s = RangedSet()
+    assert s.max() is None
+    assert s.min() is None
+    s.add(0, 10)
+    assert s.max() == 10
+    assert s.min() == 0
+    s.add(0, 5)
+    assert s.max() == 10
+    assert s.min() == 0
+    s.add(0, 11)
+    assert s.max() == 11
+    assert s.min() == 0
+    s.add(15, 20)
+    assert s.max() == 20
+    assert s.min() == 0
+    s.add(-10, -5)
+    assert s.max() == 20
+    assert s.min() == -10
+
 class RangeTest(TestCase):
 
   def testIntersect1(self):