python: improve Query.count_messages docstring

[notmuch] / bindings / python / notmuch / message.py

diff --git a/bindings/python/notmuch/message.py b/bindings/python/notmuch/message.py
index fa6c58c36afab977bbee58b6762a2a676f550885..883ed233c7e170fbfcab9b58aca2676f31417920 100644 (file)
--- a/bindings/python/notmuch/message.py
+++ b/bindings/python/notmuch/message.py
@@ -117,7 +117,7 @@ class Messages(object):
         :TODO: Make the iterator work more than once and cache the tags in
                the Python object.(?)
         """
-        if msgs_p is None:
+        if not msgs_p:
             raise NotmuchError(STATUS.NULL_POINTER)
 
         self._msgs = msgs_p
@@ -234,10 +234,10 @@ class Messages(object):
                 next_indent = indent + 1
 
             # get replies and print them also out (if there are any)
-            replies = msg.get_replies()
-            if not replies is None:
+            replies = msg.get_replies().format_messages(format, next_indent, entire_thread)
+            if replies:
                 result.append(set_sep)
-                result.extend(replies.format_messages(format, next_indent, entire_thread))
+                result.extend(replies)
 
             result.append(set_end)
         result.append(set_end)
@@ -255,6 +255,17 @@ class Messages(object):
         """
         handle.write(''.join(self.format_messages(format, indent, entire_thread)))
 
+
+class EmptyMessagesResult(Messages):
+    def __init__(self, parent):
+        self._msgs = None
+        self._parent = parent
+
+    def __next__(self):
+        raise StopIteration()
+    next = __next__
+
+
 class Message(Python3StringMixIn):
     """Represents a single Email message
 
@@ -338,7 +349,7 @@ class Message(Python3StringMixIn):
               automatically delete the parent object once all derived
               objects are dead.
         """
-        if msg_p is None:
+        if not msg_p:
             raise NotmuchError(STATUS.NULL_POINTER)
         self._msg = msg_p
         #keep reference to parent, so we keep it alive
@@ -353,7 +364,7 @@ class Message(Python3StringMixIn):
         """
         if self._msg is None:
             raise NotmuchError(STATUS.NOT_INITIALIZED)
-        return Message._get_message_id(self._msg).decode('utf-8', errors='ignore')
+        return Message._get_message_id(self._msg).decode('utf-8', 'ignore')
 
     def get_thread_id(self):
         """Returns the thread ID
@@ -371,7 +382,7 @@ class Message(Python3StringMixIn):
         if self._msg is None:
             raise NotmuchError(STATUS.NOT_INITIALIZED)
 
-        return Message._get_thread_id(self._msg).decode('utf-8', errors='ignore')
+        return Message._get_thread_id(self._msg).decode('utf-8', 'ignore')
 
     def get_replies(self):
         """Gets all direct replies to this message as :class:`Messages`
@@ -385,10 +396,9 @@ class Message(Python3StringMixIn):
             number of subsequent calls to :meth:`get_replies`). If this message
             was obtained through some non-thread means, (such as by a call to
             :meth:`Query.search_messages`), then this function will return
-            `None`.
+            an empty Messages iterator.
 
-        :returns: :class:`Messages` or `None` if there are no replies to
-            this message.
+        :returns: :class:`Messages`.
         :exception: :exc:`NotmuchError` STATUS.NOT_INITIALIZED if the message
                     is not initialized.
         """
@@ -397,8 +407,8 @@ class Message(Python3StringMixIn):
 
         msgs_p = Message._get_replies(self._msg)
 
-        if msgs_p is None:
-            return None
+        if not msgs_p:
+            return EmptyMessagesResult(self)
 
         return Messages(msgs_p, self)
 
@@ -444,7 +454,7 @@ class Message(Python3StringMixIn):
         header = Message._get_header(self._msg, _str(header))
         if header == None:
             raise NotmuchError(STATUS.NULL_POINTER)
-        return header.decode('UTF-8', errors='ignore')
+        return header.decode('UTF-8', 'ignore')
 
     def get_filename(self):
         """Returns the file path of the message file
@@ -455,7 +465,7 @@ class Message(Python3StringMixIn):
         """
         if self._msg is None:
             raise NotmuchError(STATUS.NOT_INITIALIZED)
-        return Message._get_filename(self._msg).decode('utf-8', errors='ignore')
+        return Message._get_filename(self._msg).decode('utf-8', 'ignore')
 
     def get_filenames(self):
         """Get all filenames for the email corresponding to 'message'