python: refactor the error handling machinery

Raise specific error classes instead of a generic NotmuchError with an
magic status value (e.g. NotmuchError(STATUS.NULL_POINTER) ->
NullPointerError()), update the documentation accordingly.

Signed-off-by: Justus Winter <4winter@informatik.uni-hamburg.de>

5 files changed, 165 insertions, 161 deletions

diff --git a/bindings/python/notmuch/database.py b/bindings/python/notmuch/database.py
index 6edb18b6..3de0f2b8 100644
--- a/bindings/python/notmuch/database.py
+++ b/bindings/python/notmuch/database.py
@@ -23,7 +23,9 @@ from ctypes import c_char_p, c_void_p, c_uint, c_long, byref, POINTER
 from notmuch.globals import (
     nmlib,
     STATUS,
+    FileError,
     NotmuchError,
+    NullPointerError,
     NotInitializedError,
     Enum,
     _str,
@@ -355,9 +357,8 @@ class Database(object):
             # we got an absolute path
             if not path.startswith(self.get_path()):
                 # but its initial components are not equal to the db path
-                raise NotmuchError(STATUS.FILE_ERROR,
-                                   message="Database().get_directory() called "
-                                           "with a wrong absolute path.")
+                raise FileError('Database().get_directory() called '
+                                'with a wrong absolute path')
             abs_dirpath = path
         else:
             #we got a relative path, make it absolute
@@ -542,7 +543,7 @@ class Database(object):
         self._assert_db_is_initialized()
         tags_p = Database._get_all_tags(self._db)
         if tags_p == None:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         return Tags(tags_p, self)
 
     def create_query(self, querystring):
@@ -636,7 +637,7 @@ class Directory(object):
         """Raises a NotmuchError(:attr:`STATUS`.NOT_INITIALIZED)
         if dir_p is None"""
         if not self._dir_p:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
     def __init__(self, path, dir_p, parent):
         """
@@ -797,7 +798,7 @@ class Filenames(object):
 
     def __next__(self):
         if not self._files_p:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         if not self._valid(self._files_p):
             self._files_p = None
@@ -824,7 +825,7 @@ class Filenames(object):
                      for file in files: print file
         """
         if not self._files_p:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         i = 0
         while self._valid(self._files_p):
diff --git a/bindings/python/notmuch/filename.py b/bindings/python/notmuch/filename.py
index 322e6bf1..353eb76e 100644
--- a/bindings/python/notmuch/filename.py
+++ b/bindings/python/notmuch/filename.py
@@ -17,8 +17,14 @@ along with notmuch.  If not, see <http://www.gnu.org/licenses/>.
 Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
 """
 from ctypes import c_char_p
-from notmuch.globals import (nmlib, STATUS, NotmuchError,
-    NotmuchFilenamesP, NotmuchMessageP, Python3StringMixIn)
+from notmuch.globals import (
+    nmlib,
+    NullPointerError,
+    NotInitializedError,
+    NotmuchMessageP,
+    NotmuchFilenamesP,
+    Python3StringMixIn,
+)
 
 
 class Filenames(Python3StringMixIn):
@@ -29,9 +35,9 @@ class Filenames(Python3StringMixIn):
     iterator over a list of notmuch filenames. Do note that the underlying
     library only provides a one-time iterator (it cannot reset the iterator to
     the start). Thus iterating over the function will "exhaust" the list of
-    tags, and a subsequent iteration attempt will raise a :exc:`NotmuchError`
-    STATUS.NOT_INITIALIZED. Also note, that any function that uses iteration
-    (nearly all) will also exhaust the tags. So both::
+    tags, and a subsequent iteration attempt will raise a
+    :exc:`NotInitializedError`. Also note, that any function that uses
+    iteration (nearly all) will also exhaust the tags. So both::
 
       for name in filenames: print name
 
@@ -61,8 +67,8 @@ class Filenames(Python3StringMixIn):
              will almost never instantiate a :class:`Tags` object
              herself. They are usually handed back as a result,
              e.g. in :meth:`Database.get_all_tags`.  *tags_p* must be
-             valid, we will raise an :exc:`NotmuchError`
-             (STATUS.NULL_POINTER) if it is `None`.
+             valid, we will raise an :exc:`NullPointerError`
+             if it is `None`.
         :type files_p: :class:`ctypes.c_void_p`
         :param parent: The parent object (ie :class:`Message` these
              filenames are derived from, and saves a
@@ -70,7 +76,7 @@ class Filenames(Python3StringMixIn):
              once all derived objects are dead.
         """
         if not files_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
 
         self._files = files_p
         #save reference to parent object so we keep it alive
@@ -90,7 +96,7 @@ class Filenames(Python3StringMixIn):
         This is the main function that will usually be used by the
         user."""
         if not self._files:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         while self._valid(self._files):
             yield Filenames._get(self._files).decode('utf-8', 'ignore')
@@ -104,7 +110,7 @@ class Filenames(Python3StringMixIn):
         .. note:: As this iterates over the filenames, we will not be
                able to iterate over them again (as in retrieve them)! If
                the tags have been exhausted already, this will raise a
-               :exc:`NotmuchError` STATUS.NOT_INITIALIZED on subsequent
+               :exc:`NotInitializedError` on subsequent
                attempts. However, you can use
                :meth:`Message.get_filenames` repeatedly to perform
                various actions on filenames.
diff --git a/bindings/python/notmuch/message.py b/bindings/python/notmuch/message.py
index 28723c10..b291f9fa 100644
--- a/bindings/python/notmuch/message.py
+++ b/bindings/python/notmuch/message.py
@@ -22,8 +22,19 @@ Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
 from ctypes import c_char_p, c_long, c_uint, c_int
 from datetime import date
 from notmuch.globals import (
-    nmlib, STATUS, NotmuchError, Enum, _str, Python3StringMixIn,
-    NotmuchTagsP, NotmuchMessagesP, NotmuchMessageP, NotmuchFilenamesP)
+    nmlib,
+    Enum,
+    _str,
+    Python3StringMixIn,
+    STATUS,
+    NotmuchError,
+    NullPointerError,
+    NotInitializedError,
+    NotmuchTagsP,
+    NotmuchMessageP,
+    NotmuchMessagesP,
+    NotmuchFilenamesP,
+)
 from notmuch.tag import Tags
 from notmuch.filename import Filenames
 import sys
@@ -43,7 +54,7 @@ class Messages(object):
     only provides a one-time iterator (it cannot reset the iterator to
     the start). Thus iterating over the function will "exhaust" the list
     of messages, and a subsequent iteration attempt will raise a
-    :exc:`NotmuchError` STATUS.NOT_INITIALIZED. If you need to
+    :exc:`NotInitializedError`. If you need to
     re-iterate over a list of messages you will need to retrieve a new
     :class:`Messages` object or cache your :class:`Message`\s in a list
     via::
@@ -107,8 +118,8 @@ class Messages(object):
              will almost never instantiate a :class:`Messages` object
              herself. They are usually handed back as a result,
              e.g. in :meth:`Query.search_messages`.  *msgs_p* must be
-             valid, we will raise an :exc:`NotmuchError`
-             (STATUS.NULL_POINTER) if it is `None`.
+             valid, we will raise an :exc:`NullPointerError` if it is
+             `None`.
         :type msgs_p: :class:`ctypes.c_void_p`
         :param parent: The parent object
              (ie :class:`Query`) these tags are derived from. It saves
@@ -118,7 +129,7 @@ class Messages(object):
                the Python object.(?)
         """
         if not msgs_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
 
         self._msgs = msgs_p
         #store parent, so we keep them alive as long as self  is alive
@@ -128,7 +139,7 @@ class Messages(object):
         """Return the unique :class:`Tags` in the contained messages
 
         :returns: :class:`Tags`
-        :exceptions: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if not init'ed
+        :exceptions: :exc:`NotInitializedError` if not init'ed
 
         .. note::
 
@@ -136,7 +147,7 @@ class Messages(object):
             will not allow further iterations.
         """
         if not self._msgs:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         # collect all tags (returns NULL on error)
         tags_p = Messages._collect_tags(self._msgs)
@@ -144,7 +155,7 @@ class Messages(object):
         self._msgs = None
 
         if tags_p == None:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         return Tags(tags_p, self)
 
     def __iter__(self):
@@ -161,7 +172,7 @@ class Messages(object):
 
     def __next__(self):
         if not self._msgs:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         if not self._valid(self._msgs):
             self._msgs = None
@@ -341,8 +352,8 @@ class Message(Python3StringMixIn):
     def __init__(self, msg_p, parent=None):
         """
         :param msg_p: A pointer to an internal notmuch_message_t
-            Structure.  If it is `None`, we will raise an :exc:`NotmuchError`
-            STATUS.NULL_POINTER.
+            Structure.  If it is `None`, we will raise an
+            :exc:`NullPointerError`.
 
         :param parent: A 'parent' object is passed which this message is
               derived from. We save a reference to it, so we can
@@ -350,7 +361,7 @@ class Message(Python3StringMixIn):
               objects are dead.
         """
         if not msg_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         self._msg = msg_p
         #keep reference to parent, so we keep it alive
         self._parent = parent
@@ -359,11 +370,11 @@ class Message(Python3StringMixIn):
         """Returns the message ID
 
         :returns: String with a message ID
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
                     is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Message._get_message_id(self._msg).decode('utf-8', 'ignore')
 
     def get_thread_id(self):
@@ -376,11 +387,11 @@ class Message(Python3StringMixIn):
         message belongs to a single thread.
 
         :returns: String with a thread ID
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
                     is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         return Message._get_thread_id(self._msg).decode('utf-8', 'ignore')
 
@@ -399,11 +410,11 @@ class Message(Python3StringMixIn):
             an empty Messages iterator.
 
         :returns: :class:`Messages`.
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
                     is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         msgs_p = Message._get_replies(self._msg)
 
@@ -421,11 +432,11 @@ class Message(Python3StringMixIn):
 
         :returns: A time_t timestamp.
         :rtype: c_unit64
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
                     is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Message._get_date(self._msg)
 
     def get_header(self, header):
@@ -441,30 +452,28 @@ class Message(Python3StringMixIn):
                        It is not case-sensitive.
         :type header: str
         :returns: The header value as string
-        :exception: :exc:`NotmuchError`
-
-                    * STATUS.NOT_INITIALIZED if the message
-                      is not initialized.
-                    * STATUS.NULL_POINTER if any error occured.
+        :raises: :exc:`NotInitializedError` if the message is not
+                 initialized
+        :raises: :exc:`NullPointerError` if any error occured
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         #Returns NULL if any error occurs.
         header = Message._get_header(self._msg, _str(header))
         if header == None:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         return header.decode('UTF-8', 'ignore')
 
     def get_filename(self):
         """Returns the file path of the message file
 
         :returns: Absolute file path & name of the message file
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
               is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Message._get_filename(self._msg).decode('utf-8', 'ignore')
 
     def get_filenames(self):
@@ -474,7 +483,7 @@ class Message(Python3StringMixIn):
         messages recorded to have the same Message-ID. These files must
         not necessarily have identical content."""
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         files_p = Message._get_filenames(self._msg)
 
@@ -490,11 +499,11 @@ class Message(Python3StringMixIn):
         :param flag: One of the :attr:`Message.FLAG` values (currently only
                      *Message.FLAG.MATCH*
         :returns: An unsigned int (0/1), indicating whether the flag is set.
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
               is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Message._get_flag(self._msg, flag)
 
     def set_flag(self, flag, value):
@@ -505,29 +514,27 @@ class Message(Python3StringMixIn):
         :param value: A bool indicating whether to set or unset the flag.
 
         :returns: Nothing
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
               is not initialized.
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         self._set_flag(self._msg, flag, value)
 
     def get_tags(self):
         """Returns the message tags
 
         :returns: A :class:`Tags` iterator.
-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if the message
-                        is not initialized.
-                      * STATUS.NULL_POINTER, on error
+        :raises: :exc:`NotInitializedError` if the message is not
+                 initialized
+        :raises: :exc:`NullPointerError` if any error occured
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         tags_p = Message._get_tags(self._msg)
         if tags_p == None:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         return Tags(tags_p, self)
 
     _add_tag = nmlib.notmuch_message_add_tag
@@ -552,21 +559,16 @@ class Message(Python3StringMixIn):
 
         :returns: STATUS.SUCCESS if the tag was successfully added.
                   Raises an exception otherwise.
-        :exception: :exc:`NotmuchError`. They have the following meaning:
-
-                  STATUS.NULL_POINTER
-                    The 'tag' argument is NULL
-                  STATUS.TAG_TOO_LONG
-                    The length of 'tag' is too long
-                    (exceeds Message.NOTMUCH_TAG_MAX)
-                  STATUS.READ_ONLY_DATABASE
-                    Database was opened in read-only mode so message cannot be
-                    modified.
-                  STATUS.NOT_INITIALIZED
-                     The message has not been initialized.
-       """
+        :raises: :exc:`NullPointerError` if the `tag` argument is NULL
+        :raises: :exc:`TagTooLongError` if the length of `tag` exceeds
+                 Message.NOTMUCH_TAG_MAX)
+        :raises: :exc:`ReadOnlyDatabaseError` if the database was opened
+                 in read-only mode so message cannot be modified
+        :raises: :exc:`NotInitializedError` if message has not been
+                 initialized
+        """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         status = self._add_tag(self._msg, _str(tag))
 
@@ -600,21 +602,16 @@ class Message(Python3StringMixIn):
         :returns: STATUS.SUCCESS if the tag was successfully removed or if
                   the message had no such tag.
                   Raises an exception otherwise.
-        :exception: :exc:`NotmuchError`. They have the following meaning:
-
-                   STATUS.NULL_POINTER
-                     The 'tag' argument is NULL
-                   STATUS.TAG_TOO_LONG
-                     The length of 'tag' is too long
-                     (exceeds NOTMUCH_TAG_MAX)
-                   STATUS.READ_ONLY_DATABASE
-                     Database was opened in read-only mode so message cannot
-                     be modified.
-                   STATUS.NOT_INITIALIZED
-                     The message has not been initialized.
+        :raises: :exc:`NullPointerError` if the `tag` argument is NULL
+        :raises: :exc:`TagTooLongError` if the length of `tag` exceeds
+                 Message.NOTMUCH_TAG_MAX)
+        :raises: :exc:`ReadOnlyDatabaseError` if the database was opened
+                 in read-only mode so message cannot be modified
+        :raises: :exc:`NotInitializedError` if message has not been
+                 initialized
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         status = self._remove_tag(self._msg, _str(tag))
         # bail out on error
@@ -646,16 +643,13 @@ class Message(Python3StringMixIn):
 
         :returns: STATUS.SUCCESS if the tags were successfully removed.
                   Raises an exception otherwise.
-        :exception: :exc:`NotmuchError`. They have the following meaning:
-
-                   STATUS.READ_ONLY_DATABASE
-                     Database was opened in read-only mode so message cannot
-                     be modified.
-                   STATUS.NOT_INITIALIZED
-                     The message has not been initialized.
+        :raises: :exc:`ReadOnlyDatabaseError` if the database was opened
+                 in read-only mode so message cannot be modified
+        :raises: :exc:`NotInitializedError` if message has not been
+                 initialized
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         status = self._remove_all_tags(self._msg)
 
@@ -704,16 +698,13 @@ class Message(Python3StringMixIn):
 
         :returns: STATUS.SUCCESS if the message was successfully frozen.
                   Raises an exception otherwise.
-        :exception: :exc:`NotmuchError`. They have the following meaning:
-
-                   STATUS.READ_ONLY_DATABASE
-                     Database was opened in read-only mode so message cannot
-                     be modified.
-                   STATUS.NOT_INITIALIZED
-                     The message has not been initialized.
+        :raises: :exc:`ReadOnlyDatabaseError` if the database was opened
+                 in read-only mode so message cannot be modified
+        :raises: :exc:`NotInitializedError` if message has not been
+                 initialized
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         status = self._freeze(self._msg)
 
@@ -742,17 +733,15 @@ class Message(Python3StringMixIn):
 
         :returns: STATUS.SUCCESS if the message was successfully frozen.
                   Raises an exception otherwise.
-        :exception: :exc:`NotmuchError`. They have the following meaning:
-
-                   STATUS.UNBALANCED_FREEZE_THAW
-                     An attempt was made to thaw an unfrozen message.
-                     That is, there have been an unbalanced number of calls
-                     to :meth:`freeze` and :meth:`thaw`.
-                   STATUS.NOT_INITIALIZED
-                     The message has not been initialized.
+        :raises: :exc:`UnbalancedFreezeThawError` if an attempt was made
+                 to thaw an unfrozen message. That is, there have been
+                 an unbalanced number of calls to :meth:`freeze` and
+                 :meth:`thaw`.
+        :raises: :exc:`NotInitializedError` if message has not been
+                 initialized
         """
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         status = self._thaw(self._msg)
 
@@ -788,7 +777,7 @@ class Message(Python3StringMixIn):
         :returns: a :class:`STATUS` value. In short, you want to see
             notmuch.STATUS.SUCCESS here. See there for details."""
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Message._tags_to_maildir_flags(self._msg)
 
     def maildir_flags_to_tags(self):
@@ -815,7 +804,7 @@ class Message(Python3StringMixIn):
         :returns: a :class:`STATUS`. In short, you want to see
             notmuch.STATUS.SUCCESS here. See there for details."""
         if not self._msg:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Message._tags_to_maildir_flags(self._msg)
 
     def __repr__(self):
diff --git a/bindings/python/notmuch/tag.py b/bindings/python/notmuch/tag.py
index d0f7bb40..526e51cd 100644
--- a/bindings/python/notmuch/tag.py
+++ b/bindings/python/notmuch/tag.py
@@ -17,7 +17,13 @@ along with notmuch.  If not, see <http://www.gnu.org/licenses/>.
 Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
 """
 from ctypes import c_char_p
-from notmuch.globals import nmlib, STATUS, NotmuchError, NotmuchTagsP, Python3StringMixIn
+from notmuch.globals import (
+    nmlib,
+    Python3StringMixIn,
+    NullPointerError,
+    NotInitializedError,
+    NotmuchTagsP,
+)
 
 
 class Tags(Python3StringMixIn):
@@ -29,9 +35,9 @@ class Tags(Python3StringMixIn):
     Do note that the underlying library only provides a one-time
     iterator (it cannot reset the iterator to the start). Thus iterating
     over the function will "exhaust" the list of tags, and a subsequent
-    iteration attempt will raise a :exc:`NotmuchError`
-    STATUS.NOT_INITIALIZED. Also note, that any function that uses
-    iteration (nearly all) will also exhaust the tags. So both::
+    iteration attempt will raise a :exc:`NotInitializedError`.
+    Also note, that any function that uses iteration (nearly all) will
+    also exhaust the tags. So both::
 
       for tag in tags: print tag
 
@@ -60,8 +66,8 @@ class Tags(Python3StringMixIn):
              will almost never instantiate a :class:`Tags` object
              herself. They are usually handed back as a result,
              e.g. in :meth:`Database.get_all_tags`.  *tags_p* must be
-             valid, we will raise an :exc:`NotmuchError`
-             (STATUS.NULL_POINTER) if it is `None`.
+             valid, we will raise an :exc:`NullPointerError` if it is
+             `None`.
         :type tags_p: :class:`ctypes.c_void_p`
         :param parent: The parent object (ie :class:`Database` or
              :class:`Message` these tags are derived from, and saves a
@@ -71,7 +77,7 @@ class Tags(Python3StringMixIn):
                cache the tags in the Python object(?)
         """
         if not tags_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
 
         self._tags = tags_p
         #save reference to parent object so we keep it alive
@@ -91,7 +97,7 @@ class Tags(Python3StringMixIn):
 
     def __next__(self):
         if not self._tags:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         if not self._valid(self._tags):
             self._tags = None
             raise StopIteration
@@ -118,8 +124,8 @@ class Tags(Python3StringMixIn):
 
             As this iterates over the tags, we will not be able to iterate over
             them again (as in retrieve them)! If the tags have been exhausted
-            already, this will raise a :exc:`NotmuchError`
-            STATUS.NOT_INITIALIZED on subsequent attempts.
+            already, this will raise a :exc:`NotInitializedError`on subsequent
+            attempts.
         """
         return " ".join(self)
 
diff --git a/bindings/python/notmuch/thread.py b/bindings/python/notmuch/thread.py
index c2347fe7..5c580288 100644
--- a/bindings/python/notmuch/thread.py
+++ b/bindings/python/notmuch/thread.py
@@ -18,9 +18,16 @@ Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
 """
 
 from ctypes import c_char_p, c_long, c_int
-from notmuch.globals import (nmlib, STATUS,
-    NotmuchError, NotmuchThreadP, NotmuchThreadsP, NotmuchMessagesP,
-    NotmuchTagsP, Python3StringMixIn)
+from notmuch.globals import (
+    nmlib,
+    Python3StringMixIn,
+    NullPointerError,
+    NotInitializedError,
+    NotmuchThreadP,
+    NotmuchThreadsP,
+    NotmuchMessagesP,
+    NotmuchTagsP,
+)
 from notmuch.message import Messages
 from notmuch.tag import Tags
 from datetime import date
@@ -35,7 +42,7 @@ class Threads(Python3StringMixIn):
     library only provides a one-time iterator (it cannot reset the
     iterator to the start). Thus iterating over the function will
     "exhaust" the list of threads, and a subsequent iteration attempt
-    will raise a :exc:`NotmuchError` STATUS.NOT_INITIALIZED. Also
+    will raise a :exc:`NotInitializedError`. Also
     note, that any function that uses iteration will also
     exhaust the messages. So both::
 
@@ -87,8 +94,8 @@ class Threads(Python3StringMixIn):
              will almost never instantiate a :class:`Threads` object
              herself. They are usually handed back as a result,
              e.g. in :meth:`Query.search_threads`.  *threads_p* must be
-             valid, we will raise an :exc:`NotmuchError`
-             (STATUS.NULL_POINTER) if it is `None`.
+             valid, we will raise an :exc:`NullPointerError` if it is
+             `None`.
         :type threads_p: :class:`ctypes.c_void_p`
         :param parent: The parent object
              (ie :class:`Query`) these tags are derived from. It saves
@@ -98,7 +105,7 @@ class Threads(Python3StringMixIn):
                the Python object.(?)
         """
         if not threads_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
 
         self._threads = threads_p
         #store parent, so we keep them alive as long as self  is alive
@@ -118,7 +125,7 @@ class Threads(Python3StringMixIn):
 
     def __next__(self):
         if not self._threads:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         if not self._valid(self._threads):
             self._threads = None
@@ -138,11 +145,11 @@ class Threads(Python3StringMixIn):
                  #THIS FAILS
                  threads = Database().create_query('').search_threads()
                  if len(threads) > 0:              #this 'exhausts' threads
-                     # next line raises NotmuchError(STATUS.NOT_INITIALIZED)!!!
+                     # next line raises :exc:`NotInitializedError`!!!
                      for thread in threads: print thread
         """
         if not self._threads:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         i = 0
         # returns 'bool'. On out-of-memory it returns None
@@ -220,8 +227,8 @@ class Thread(object):
             will almost never instantiate a :class:`Thread` object
             herself. They are usually handed back as a result,
             e.g. when iterating through :class:`Threads`. *thread_p*
-            must be valid, we will raise an :exc:`NotmuchError`
-            (STATUS.NULL_POINTER) if it is `None`.
+            must be valid, we will raise an :exc:`NullPointerError`
+            if it is `None`.
 
         :param parent: A 'parent' object is passed which this message is
               derived from. We save a reference to it, so we can
@@ -229,7 +236,7 @@ class Thread(object):
               objects are dead.
         """
         if not thread_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         self._thread = thread_p
         #keep reference to parent, so we keep it alive
         self._parent = parent
@@ -241,11 +248,11 @@ class Thread(object):
         for as long as the thread is valid.
 
         :returns: String with a message ID
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the thread
+        :exception: :exc:`NotInitializedError` if the thread
                     is not initialized.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Thread._get_thread_id(self._thread).decode('utf-8', 'ignore')
 
     _get_total_messages = nmlib.notmuch_thread_get_total_messages
@@ -258,11 +265,11 @@ class Thread(object):
         :returns: The number of all messages in the database
                   belonging to this thread. Contrast with
                   :meth:`get_matched_messages`.
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the thread
+        :exception: :exc:`NotInitializedError` if the thread
                     is not initialized.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return self._get_total_messages(self._thread)
 
     def get_toplevel_messages(self):
@@ -279,18 +286,16 @@ class Thread(object):
            messages, etc.).
 
         :returns: :class:`Messages`
-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if query is not inited
-                      * STATUS.NULL_POINTER if search_messages failed
+        :raises: :exc:`NotInitializedError` if query is not initialized
+        :raises: :exc:`NullPointerError` if search_messages failed
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         msgs_p = Thread._get_toplevel_messages(self._thread)
 
         if not msgs_p:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
 
         return Messages(msgs_p, self)
 
@@ -304,11 +309,11 @@ class Thread(object):
         :returns: The number of all messages belonging to this thread that
                   matched the :class:`Query`from which this thread was created.
                   Contrast with :meth:`get_total_messages`.
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the thread
+        :exception: :exc:`NotInitializedError` if the thread
                     is not initialized.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return self._get_matched_messages(self._thread)
 
     def get_authors(self):
@@ -322,7 +327,7 @@ class Thread(object):
         as long as this Thread() is not deleted.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         authors = Thread._get_authors(self._thread)
         if not authors:
             return None
@@ -335,7 +340,7 @@ class Thread(object):
         as long as this Thread() is not deleted.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         subject = Thread._get_subject(self._thread)
         if not subject:
             return None
@@ -346,11 +351,11 @@ class Thread(object):
 
         :returns: A time_t timestamp.
         :rtype: c_unit64
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
                     is not initialized.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Thread._get_newest_date(self._thread)
 
     def get_oldest_date(self):
@@ -358,11 +363,11 @@ class Thread(object):
 
         :returns: A time_t timestamp.
         :rtype: c_unit64
-        :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
+        :exception: :exc:`NotInitializedError` if the message
                     is not initialized.
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
         return Thread._get_oldest_date(self._thread)
 
     def get_tags(self):
@@ -378,18 +383,15 @@ class Thread(object):
         query from which it derived is explicitely deleted).
 
         :returns: A :class:`Tags` iterator.
-        :exception: :exc:`NotmuchError`
-
-                      * STATUS.NOT_INITIALIZED if the thread
-                        is not initialized.
-                      * STATUS.NULL_POINTER, on error
+        :raises: :exc:`NotInitializedError` if query is not initialized
+        :raises: :exc:`NullPointerError` if search_messages failed
         """
         if not self._thread:
-            raise NotmuchError(STATUS.NOT_INITIALIZED)
+            raise NotInitializedError()
 
         tags_p = Thread._get_tags(self._thread)
         if tags_p == None:
-            raise NotmuchError(STATUS.NULL_POINTER)
+            raise NullPointerError()
         return Tags(tags_p, self)
 
     def __unicode__(self):