Moves vision models to allennlp-models (#4918)

* Moves vision models to allennlp-models

* Also move test fixtures

* Don't return so many instances if we're cutting them out later anyways

* We actually need this image

* Formatting

* Fixing more paths

allennlp/data/dataset_readers/__init__.py

@@ -19,7 +19,3 @@
 from allennlp.data.dataset_readers.sequence_tagging import SequenceTaggingDatasetReader
 from allennlp.data.dataset_readers.sharded_dataset_reader import ShardedDatasetReader
 from allennlp.data.dataset_readers.text_classification_json import TextClassificationJsonReader
-from allennlp.data.dataset_readers.vision_reader import VisionReader
-from allennlp.data.dataset_readers.vqav2 import VQAv2Reader
-from allennlp.data.dataset_readers.visual_entailment import VisualEntailmentReader
-from allennlp.data.dataset_readers.gqa import GQAReader

allennlp/data/dataset_readers/dataset_reader.py

@@ -300,6 +300,12 @@ def shard_iterable(self, iterable: Iterable[_T]) -> Iterator[_T]:
                 sharded_slice, self._worker_info.id, None, self._worker_info.num_workers
             )
 
+        # We don't know for sure how many instances we have to produce.
+        # _multi_worker_islice() figures that out. But we know for sure
+        # it won't be more than max_instances.
+        if self.max_instances is not None:
+            sharded_slice = itertools.islice(sharded_slice, self.max_instances)
+
         return sharded_slice
 
     def _multi_worker_islice(