* Add span.sent property, re Issue #366

spacy/tests/spans/test_span.py

@@ -37,3 +37,16 @@ def test_root2():
     doc.from_array([HEAD], heads.T)
     south_carolina = doc[-2:]
     assert south_carolina.root.text == 'Carolina'
+
+
+def test_sent(doc):
+    '''Test new span.sent property'''
+    #return EN('This is a sentence. This is another sentence. And a third.')
+    heads = np.asarray([[1, 0, -1, -1, -1, 1, 0, -1, -1, -1, 2, 1, 0, -1]], dtype='int32')
+    doc.from_array([HEAD], heads.T)
+    assert len(list(doc.sents))
+    span = doc[:2]
+    assert span.sent.root.text == 'is'
+    assert span.sent.text == 'This is a sentence.'
+    span = doc[6:7]
+    assert span.sent.root.left_edge.text == 'This'

spacy/tokens/span.pyx

@@ -99,6 +99,20 @@ cdef class Span:
             self.start = start
             self.end = end + 1
 
+    property sent:
+        '''Get the sentence span that this span is a part of.'''
+        def __get__(self):
+            # This should raise if we're not parsed.
+            doc.sents
+            cdef int n = 0
+            root = &self.doc.c[self.start]
+            while root.head != 0:
+                root += root.head
+                n += 1
+                if n >= self.doc.length:
+                    raise RuntimeError
+            return self.doc[root.l_edge : root.r_edge + 1]
+    
     property vector:
         def __get__(self):
             if self._vector is None: