Raise subclasses of KeyError (#5)

* fix testing under py3.3 (could not find 'intid' in 'zope') and simplify

Bring in the .travis.yml changes from #3 and also do the same for tox.ini.

* Raise more informative KeyError subclasses.

* Make sure POSKeyError propagates.

Note that ``queryId`` now propagates this error; previously it was
hidden. This now matches the behaviour of ``queryObject`` which always
propagated.

Test this. I have 100% test coverage locally. Some minor refactoring of
the subscribers facilitates this (and reduces the nesting depth).

Also add a setup.cfg to indicate that we generate universal wheels.

* Use latest pypy3 on travis because of pip.

.coveragerc

@@ -0,0 +1,2 @@
+[run]
+source = src

.travis.yml

@@ -6,7 +6,7 @@ python:
     - 3.4
     - 3.5
     - pypy
-    - pypy3
+    - pypy3.3-5.2-alpha1
 install:
     - pip install -U pip setuptools # need updated pip for caching
     - pip install .[test]

CHANGES.rst

@@ -4,10 +4,22 @@ Changes
 4.2.0 (unreleased)
 ------------------
 
+- Raise more informative KeyError subclasses from the utility when intids
+  or objects cannot be found. This distinguishes them from errors
+  raised by normal dictionaries or BTrees, and is useful in unit
+  testing or when persisting intids or sharing them among processes
+  for later or concurrent use.
+
+- Propagate ``POSKeyError`` from ``queryId`` instead of returning the
+  default object. This exception indicates a corrupt database, not a
+  missing object. The ``queryObject`` function already behaved this way.
+
 - Add support for Python 3.5.
 
 - Drop support for Python 2.6.
 
+- Add support for PyPy3 5.2.
+
 - Stop depending on ZODB for anything except testing.
 
 4.1.0 (2014-12-27)

setup.cfg

@@ -0,0 +1,2 @@
+[bdist_wheel]
+universal = 1

src/zope/intid/__init__.py

@@ -34,6 +34,20 @@
 
 from zope.intid.interfaces import IIntIds, IIntIdEvent
 from zope.intid.interfaces import IntIdAddedEvent, IntIdRemovedEvent
+from zope.intid.interfaces import IntIdMissingError, IntIdsCorruptedError, ObjectMissingError
+
+try:
+    # POSKeyError is a subclass of KeyError; in the cases where we
+    # catch KeyError for an item missing from a BTree, we still
+    # want to propagate this exception that indicates a corrupt database
+    # (as opposed to a corrupt IntIds)
+    from ZODB.POSException import POSKeyError as _POSKeyError
+except ImportError: # pragma: no cover (we run tests with ZODB installed)
+    # In practice, ZODB will probably be installed. But if not,
+    # then POSKeyError can never be generated, so use a unique
+    # exception that we'll never catch.
+    class _POSKeyError(BaseException):
+        pass
 
 @implementer(IIntIds, IContained)
 class IntIds(Persistent):
@@ -67,7 +81,12 @@ def __iter__(self):
         return self.refs.iterkeys()
 
     def getObject(self, id):
-        return self.refs[id]()
+        try:
+            return self.refs[id]()
+        except _POSKeyError:
+            raise
+        except KeyError:
+            raise ObjectMissingError(id)
 
     def queryObject(self, id, default=None):
         r = self.refs.get(id)
@@ -79,16 +98,20 @@ def getId(self, ob):
         try:
             key = IKeyReference(ob)
         except (NotYet, TypeError, ValueError):
-            raise KeyError(ob)
+            raise IntIdMissingError(ob)
 
         try:
             return self.ids[key]
+        except _POSKeyError:
+            raise
         except KeyError:
-            raise KeyError(ob)
+            raise IntIdMissingError(ob)
 
     def queryId(self, ob, default=None):
         try:
             return self.getId(ob)
+        except _POSKeyError:
+            raise
         except KeyError:
             return default
 
@@ -131,10 +154,27 @@ def unregister(self, ob):
         if key is None:
             return
 
-        uid = self.ids[key]
-        del self.refs[uid]
+        try:
+            uid = self.ids[key]
+        except _POSKeyError:
+            raise
+        except KeyError:
+            raise IntIdMissingError(ob)
+
+        try:
+            del self.refs[uid]
+        except _POSKeyError:
+            raise
+        except KeyError:
+            # It was in self.ids, but not self.refs. Something is corrupted.
+            # We've always let this KeyError propagate, before cleaning up self.ids,
+            # meaning that getId(ob) will continue to work, but getObject(uid) will not.
+            raise IntIdsCorruptedError(ob, uid)
         del self.ids[key]
 
+def _utilities_and_key(ob):
+    utilities = tuple(getAllUtilitiesRegisteredFor(IIntIds))
+    return utilities, IKeyReference(ob, None) if utilities else None
 
 @adapter(ILocation, IObjectRemovedEvent)
 def removeIntIdSubscriber(ob, event):
@@ -143,18 +183,18 @@ def removeIntIdSubscriber(ob, event):
     Removes the unique ids registered for the object in all the unique
     id utilities.
     """
-    utilities = tuple(getAllUtilitiesRegisteredFor(IIntIds))
-    if utilities:
-        key = IKeyReference(ob, None)
-        # Register only objects that adapt to key reference
-        if key is not None:
-            # Notify the catalogs that this object is about to be removed.
-            notify(IntIdRemovedEvent(ob, event))
-            for utility in utilities:
-                try:
-                    utility.unregister(key)
-                except KeyError:
-                    pass
+    utilities, key = _utilities_and_key(ob)
+    if not utilities or key is None:
+        # Unregister only objects that adapt to key reference
+        return
+    # Notify the catalogs that this object is about to be removed.
+    notify(IntIdRemovedEvent(ob, event))
+    for utility in utilities:
+        try:
+            utility.unregister(key)
+        except KeyError:
+            # Silently ignoring all kinds corruption here
+            pass
 
 @adapter(ILocation, IObjectAddedEvent)
 def addIntIdSubscriber(ob, event):
@@ -163,16 +203,15 @@ def addIntIdSubscriber(ob, event):
     Registers the object added in all unique id utilities and fires
     an event for the catalogs.
     """
-    utilities = tuple(getAllUtilitiesRegisteredFor(IIntIds))
-    if utilities: # assert that there are any utilites
-        key = IKeyReference(ob, None)
+    utilities, key = _utilities_and_key(ob)
+    if not utilities or key is None:
         # Register only objects that adapt to key reference
-        if key is not None:
-            idmap = {}
-            for utility in utilities:
-                idmap[utility] = utility.register(key)
-            # Notify the catalogs that this object was added.
-            notify(IntIdAddedEvent(ob, event, idmap))
+        return
+    idmap = {}
+    for utility in utilities:
+        idmap[utility] = utility.register(key)
+    # Notify the catalogs that this object was added.
+    notify(IntIdAddedEvent(ob, event, idmap))
 
 @adapter(IIntIdEvent)
 def intIdEventNotify(event):

src/zope/intid/interfaces.py

@@ -2,6 +2,23 @@
 """
 from zope.interface import Interface, Attribute, implementer
 
+class IntIdMissingError(KeyError):
+    """
+    Raised when ``getId`` cannot find an intid.
+    """
+
+class ObjectMissingError(KeyError):
+    """
+    Raised when ``getObject`` cannot find an object.
+    """
+
+class IntIdsCorruptedError(KeyError):
+    """
+    Raised when internal corruption is detected in the utility.
+
+    Users should not need to catch this because this situation should
+    not happen.
+    """
 
 class IIntIdsQuery(Interface):
     "Query for IDs and objects"
@@ -43,7 +60,7 @@ def register(ob):
     def unregister(ob):
         """Remove the object from the indexes.
 
-        KeyError is raised if ob is not registered previously.
+        IntIdMissingError is raised if ob is not registered previously.
         """
 
 class IIntIdsManage(Interface):