[OPS, TEST] Add onnx test for batched_nms (#3483)

Author: NicolasHug

test/test_onnx.py

@@ -82,16 +82,30 @@ def to_numpy(tensor):
                     raise
 
     def test_nms(self):
-        boxes = torch.rand(5, 4)
-        boxes[:, 2:] += torch.rand(5, 2)
-        scores = torch.randn(5)
+        num_boxes = 100
+        boxes = torch.rand(num_boxes, 4)
+        boxes[:, 2:] += boxes[:, :2]
+        scores = torch.randn(num_boxes)
 
         class Module(torch.nn.Module):
             def forward(self, boxes, scores):
                 return ops.nms(boxes, scores, 0.5)
 
         self.run_model(Module(), [(boxes, scores)])
 
+    def test_batched_nms(self):
+        num_boxes = 100
+        boxes = torch.rand(num_boxes, 4)
+        boxes[:, 2:] += boxes[:, :2]
+        scores = torch.randn(num_boxes)
+        idxs = torch.randint(0, 5, size=(num_boxes,))
+
+        class Module(torch.nn.Module):
+            def forward(self, boxes, scores, idxs):
+                return ops.batched_nms(boxes, scores, idxs, 0.5)
+
+        self.run_model(Module(), [(boxes, scores, idxs)])
+
     def test_clip_boxes_to_image(self):
         boxes = torch.randn(5, 4) * 500
         boxes[:, 2:] += boxes[:, :2]