Implement inotify-only FileClosedEvent

This is a slightly modernised and updated version of the PR
gorakhargosh#245.

Native event tracking issue for reference:

 * gorakhargosh#217

src/watchdog/events.py

@@ -97,6 +97,7 @@
 EVENT_TYPE_DELETED = 'deleted'
 EVENT_TYPE_CREATED = 'created'
 EVENT_TYPE_MODIFIED = 'modified'
+EVENT_TYPE_CLOSED = 'closed'
 
 
 class FileSystemEvent(object):
@@ -240,6 +241,25 @@ def __repr__(self):
                           dest_path=self.dest_path))
 
 
+class FileClosedEvent(FileSystemEvent):
+    """
+    File system event representing file closure on the file system. (inotify
+    only)
+    """
+
+    event_type = EVENT_TYPE_CLOSED
+
+    def __init__(self, src_path, closed_write):
+        super(FileClosedEvent, self).__init__(src_path)
+        self.closed_write = closed_write
+
+    def __repr__(self):
+        return ("<%(class_name)s: src_path=%(src_path)r, "
+                "closed_write=%(closed_write)r>"
+                ) % (dict(class_name=self.__class__.__name__,
+                          src_path=self.src_path,
+                          closed_write=self.closed_write))
+
 # Directory events.
 
 
@@ -325,6 +345,7 @@ def dispatch(self, event):
             EVENT_TYPE_MOVED: self.on_moved,
             EVENT_TYPE_CREATED: self.on_created,
             EVENT_TYPE_DELETED: self.on_deleted,
+            EVENT_TYPE_CLOSED: self.on_closed,
         }
         event_type = event.event_type
         _method_map[event_type](event)
@@ -374,6 +395,15 @@ def on_modified(self, event):
             :class:`DirModifiedEvent` or :class:`FileModifiedEvent`
         """
 
+    def on_closed(self, event):
+        """Called when a file or directory is closed (inotify only).
+
+        :param event:
+            Event representing file/directory modification.
+        :type event:
+            :class:`DirModifiedEvent` or :class:`FileModifiedEvent`
+        """
+
 
 class PatternMatchingEventHandler(FileSystemEventHandler):
     """
@@ -449,6 +479,7 @@ def dispatch(self, event):
                 EVENT_TYPE_MOVED: self.on_moved,
                 EVENT_TYPE_CREATED: self.on_created,
                 EVENT_TYPE_DELETED: self.on_deleted,
+                EVENT_TYPE_CLOSED: self.on_closed,
             }
             event_type = event.event_type
             _method_map[event_type](event)
@@ -532,6 +563,7 @@ def dispatch(self, event):
                 EVENT_TYPE_MOVED: self.on_moved,
                 EVENT_TYPE_CREATED: self.on_created,
                 EVENT_TYPE_DELETED: self.on_deleted,
+                EVENT_TYPE_CLOSED: self.on_closed,
             }
             event_type = event.event_type
             _method_map[event_type](event)
@@ -565,6 +597,12 @@ def on_modified(self, event):
         what = 'directory' if event.is_directory else 'file'
         logging.info("Modified %s: %s", what, event.src_path)
 
+    def on_close(self, event):
+        super(LoggingEventHandler, self).on_close(event)
+
+        what = 'directory' if event.is_directory else 'file'
+        logging.info("Closed %s: %s", what, event.src_path)
+
 
 class LoggingFileSystemEventHandler(LoggingEventHandler):
     """

src/watchdog/observers/inotify.py

@@ -89,6 +89,7 @@
     FileModifiedEvent,
     FileMovedEvent,
     FileCreatedEvent,
+    FileClosedEvent,
     generate_sub_moved_events,
     generate_sub_created_events,
 )
@@ -174,6 +175,10 @@ def queue_events(self, timeout, full_events=False):
                 cls = DirCreatedEvent if event.is_directory else FileCreatedEvent
                 self.queue_event(cls(src_path))
                 self.queue_event(DirModifiedEvent(os.path.dirname(src_path)))
+            elif (event.is_close_write or event.is_close_nowrite) \
+                    and not event.is_directory:
+                cls = FileClosedEvent
+                self.queue_event(cls(event.src_path, event.is_close_write))
 
     def _decode_path(self, path):
         """ Decode path only if unicode string was passed to this emitter. """

src/watchdog/observers/inotify_c.py

@@ -127,6 +127,7 @@ class InotifyConstants(object):
         InotifyConstants.IN_MOVED_TO,
         InotifyConstants.IN_CREATE,
         InotifyConstants.IN_DELETE,
+        InotifyConstants.IN_CLOSE,
         InotifyConstants.IN_DELETE_SELF,
         InotifyConstants.IN_DONT_FOLLOW,
     ])