Remove on_batch_begin and on_batch_end callbacks

gensim/models/callbacks.py

@@ -578,6 +578,11 @@ class CallbackAny2Vec:
 
     See examples at the module level docstring for how to define your own callbacks by inheriting  from this class.
 
+    As of gensim 4.0.0, the following callbacks are no longer supported, and overriding them will have no effect:
+
+    - on_batch_begin
+    - on_batch_end
+
     """
     def on_epoch_begin(self, model):
         """Method called at the start of each epoch.
@@ -601,28 +606,6 @@ def on_epoch_end(self, model):
         """
         pass
 
-    def on_batch_begin(self, model):
-        """Method called at the start of each batch.
-
-        Parameters
-        ----------
-        model : :class:`~gensim.models.word2vec.Word2Vec` or subclass
-            Current model.
-
-        """
-        pass
-
-    def on_batch_end(self, model):
-        """Method called at the end of each batch.
-
-        Parameters
-        ----------
-        model : :class:`~gensim.models.word2vec.Word2Vec` or subclass
-            Current model.
-
-        """
-        pass
-
     def on_train_begin(self, model):
         """Method called at the start of the training process.
 

gensim/models/word2vec.py

@@ -1145,22 +1145,15 @@ def _worker_loop(self, job_queue, progress_queue):
         """
         thread_private_mem = self._get_thread_working_mem()
         jobs_processed = 0
-        callbacks = progress_queue.callbacks
         while True:
             job = job_queue.get()
             if job is None:
                 progress_queue.put(None)
                 break  # no more jobs => quit this worker
             data_iterable, alpha = job
 
-            for callback in callbacks:
-                callback.on_batch_begin(self)
-
             tally, raw_tally = self._do_train_job(data_iterable, alpha, thread_private_mem)
 
-            for callback in callbacks:
-                callback.on_batch_end(self)
-
             progress_queue.put((len(data_iterable), tally, raw_tally))  # report back progress
             jobs_processed += 1
         logger.debug("worker exiting, processed %i jobs", jobs_processed)
@@ -1410,7 +1403,6 @@ def _train_epoch(
         """
         job_queue = Queue(maxsize=queue_factor * self.workers)
         progress_queue = Queue(maxsize=(queue_factor + 1) * self.workers)
-        progress_queue.callbacks = callbacks  # messy way to pass along for just this session
 
         workers = [
             threading.Thread(