Fix vectors.add()

spacy/vectors.pyx

@@ -56,6 +56,7 @@ cdef class Vectors:
         self.i = 0
         self.key2row = {}
         self.keys = numpy.zeros((self.data.shape[0],), dtype='uint64')
+        if data is not None:
             for i, string in enumerate(self.strings):
                 if i >= self.data.shape[0]:
                     break
@@ -124,25 +125,22 @@ cdef class Vectors:
         vector (numpy.ndarray / None): A vector to add for the key.
         row (int / None): The row-number of a vector to map the key to.
         """
-        if row is not None and vector is not None:
-            raise ValueError("Only one of 'row' and 'vector' may be set")
         if isinstance(key, basestring_):
             key = self.strings.add(key)
-        if key in self.key2row and vector is not None:
+        if key in self.key2row and row is None:
             row = self.key2row[key]
         elif key in self.key2row and row is not None:
             self.key2row[key] = row
-        elif key not in self.key2row:
+        elif row is None:
-            if row is not None:
-                self.key2row[key] = row
-            else:
-                self.key2row[key] = self.i
             row = self.i
+            self.i += 1
         if row >= self.keys.shape[0]:
             self.keys.resize((row*2,))
             self.data.resize((row*2, self.data.shape[1]))
             self.keys[self.i] = key
-            self.i += 1
+
+        self.key2row[key] = row
+        self.keys[row] = key
         if vector is not None:
             self.data[row] = vector
         return row