Add test for Issue #913: Hang from bad regex

spacy/tests/regression/test_issue913.py

@@ -0,0 +1,16 @@
+import pytest
+from ... import load as load_spacy
+
+
+def test_issue913(en_tokenizer):
+    '''Test that spaCy doesn't hang on many periods.'''
+    string = '0'
+    for i in range(1, 100):
+        string += '.%d' % i
+    doc = en_tokenizer(string)
+
+# Don't want tests to fail if they haven't installed pytest-timeout plugin
+try:
+    test_issue913 = pytest.mark.timeout(5)(test_issue913)
+except NameError:
+    pass