From 6be49d9b156a22460476c7d5c729fd4ff697a778 Mon Sep 17 00:00:00 2001
From: Joel Bender <joel@carrickbender.com>
Date: Tue, 26 Sep 2017 00:20:17 -0400
Subject: [PATCH] adding and removing a property

---
 py25/bacpypes/constructeddata.py |  5 +++
 py27/bacpypes/constructeddata.py |  5 +++
 py34/bacpypes/constructeddata.py |  5 +++
 sandbox/add_remove_property.py   | 59 ++++++++++++++++++++++++++++++++
 4 files changed, 74 insertions(+)
 create mode 100644 sandbox/add_remove_property.py

diff --git a/py25/bacpypes/constructeddata.py b/py25/bacpypes/constructeddata.py
index 2e589b8..1d1cade 100755
--- a/py25/bacpypes/constructeddata.py
+++ b/py25/bacpypes/constructeddata.py
@@ -600,6 +600,11 @@ def ArrayOf(klass):
             # not found
             raise ValueError("%r not in array" % (value,))
 
+        def remove(self, item):
+            # find the index of the item and delete it
+            indx = self.index(item)
+            self.__delitem__(indx)
+
         def encode(self, taglist):
             if _debug: ArrayOf._debug("(%r)encode %r", self.__class__.__name__, taglist)
 
diff --git a/py27/bacpypes/constructeddata.py b/py27/bacpypes/constructeddata.py
index 75818ad..38e491c 100755
--- a/py27/bacpypes/constructeddata.py
+++ b/py27/bacpypes/constructeddata.py
@@ -598,6 +598,11 @@ def ArrayOf(klass):
             # not found
             raise ValueError("%r not in array" % (value,))
 
+        def remove(self, item):
+            # find the index of the item and delete it
+            indx = self.index(item)
+            self.__delitem__(indx)
+
         def encode(self, taglist):
             if _debug: ArrayOf._debug("(%r)encode %r", self.__class__.__name__, taglist)
 
diff --git a/py34/bacpypes/constructeddata.py b/py34/bacpypes/constructeddata.py
index 45dc228..54b9f5a 100755
--- a/py34/bacpypes/constructeddata.py
+++ b/py34/bacpypes/constructeddata.py
@@ -598,6 +598,11 @@ def ArrayOf(klass):
             # not found
             raise ValueError("%r not in array" % (value,))
 
+        def remove(self, item):
+            # find the index of the item and delete it
+            indx = self.index(item)
+            self.__delitem__(indx)
+
         def encode(self, taglist):
             if _debug: ArrayOf._debug("(%r)encode %r", self.__class__.__name__, taglist)
 
diff --git a/sandbox/add_remove_property.py b/sandbox/add_remove_property.py
new file mode 100644
index 0000000..e5a90be
--- /dev/null
+++ b/sandbox/add_remove_property.py
@@ -0,0 +1,59 @@
+
+from bacpypes.basetypes import PropertyIdentifier
+from bacpypes.constructeddata import ArrayOf
+from bacpypes.object import AnalogValueObject
+
+# create an array of property identifiers datatype
+ArrayOfPropertyIdentifier = ArrayOf(PropertyIdentifier)
+
+aopi = ArrayOfPropertyIdentifier()
+aopi.append('objectName')
+aopi.append('objectType')
+aopi.append('description')
+aopi.debug_contents()
+
+aopi.remove('objectType')
+aopi.debug_contents()
+
+print("Create an Analog Value Object")
+av = AnalogValueObject(
+    objectName='av-sample',
+    objectIdentifier=('analogValue', 1),
+    description="sample",
+    )
+av.debug_contents()
+print("")
+
+print("Change the description")
+av.description = "something else"
+av.debug_contents()
+print("")
+
+
+# get the description property by the attribute name
+description_property = av._attr_to_property('description')
+print("description_property = %r" % (description_property,))
+print("")
+
+print("Delete the property")
+av.delete_property(description_property)
+print("...property deleted")
+
+try:
+    av.description = "this raises an exception"
+except Exception as err:
+    print(repr(err))
+av.debug_contents()
+print("")
+
+print("===== Add the property")
+av.add_property(description_property)
+print("...property added")
+
+try:
+    av.description = "this works"
+except Exception as err:
+    print(repr(err))
+av.debug_contents()
+print("")
+