Add a small bert test including testing an empty word

stanza/tests/common/test_bert_embedding.py

@@ -0,0 +1,33 @@
+import pytest
+import torch
+
+from stanza.models.common.bert_embedding import load_bert, extract_bert_embeddings
+
+pytestmark = [pytest.mark.travis, pytest.mark.pipeline]
+
+BERT_MODEL = "hf-internal-testing/tiny-bert"
+
+@pytest.fixture(scope="module")
+def tiny_bert():
+    m, t = load_bert(BERT_MODEL)
+    return m, t
+
+def test_load_bert(tiny_bert):
+    """
+    Empty method that just tests loading the bert
+    """
+    m, t = tiny_bert
+
+def test_run_bert(tiny_bert):
+    m, t = tiny_bert
+    device = next(m.parameters()).device
+    extract_bert_embeddings(BERT_MODEL, t, m, [["This", "is", "a", "test"]], device, True)
+
+def test_run_bert_empty_word(tiny_bert):
+    m, t = tiny_bert
+    device = next(m.parameters()).device
+    foo = extract_bert_embeddings(BERT_MODEL, t, m, [["This", "is", "-", "a", "test"]], device, True)
+    bar = extract_bert_embeddings(BERT_MODEL, t, m, [["This", "is", "", "a", "test"]], device, True)
+
+    assert len(foo) == 1
+    assert torch.allclose(foo[0], bar[0])