Fixes to hacky vocab pickling

spacy/cfile.pyx

@@ -57,7 +57,7 @@ cdef class StringCFile:
         self.size = len(data)
         self.data = <unsigned char*>self.mem.alloc(1, self._capacity)
         for i in range(len(data)):
-            self.data[i] = data
+            self.data[i] = data[i]
 
     def close(self):
         self.is_open = False
@@ -69,13 +69,12 @@ cdef class StringCFile:
         memcpy(dest, self.data, elem_size * number)
         self.data += elem_size * number
 
-    cdef int write_from(self, void* src, size_t number, size_t elem_size) except -1:
+    cdef int write_from(self, void* src, size_t elem_size, size_t number) except -1:
         write_size = number * elem_size
         if (self.size + write_size) >= self._capacity:
             self._capacity = (self.size + write_size) * 2
             self.data = <unsigned char*>self.mem.realloc(self.data, self._capacity)
-        memcpy(self.data, src, elem_size * number)
-        self.data += write_size
+        memcpy(&self.data[self.size], src, elem_size * number)
         self.size += write_size
 
     cdef void* alloc_read(self, Pool mem, size_t number, size_t elem_size) except *:

spacy/tests/test_pickles.py

@@ -1,9 +1,12 @@
 from __future__ import unicode_literals
 
 import io
-import pickle
+import pytest
+import dill as pickle
 
 from ..strings import StringStore
+from ..vocab import Vocab
+from ..attrs import NORM
 
 
 def test_pickle_string_store():
@@ -14,4 +17,23 @@ def test_pickle_string_store():
     unpickled = pickle.loads(bdata)
     assert unpickled['hello'] == hello
     assert unpickled['bye'] == bye
+    assert len(sstore) == len(unpickled)
 
+
+def test_pickle_vocab():
+    vocab = Vocab(lex_attr_getters={int(NORM): lambda string: string[:-1]})
+    dog = vocab[u'dog']
+    cat = vocab[u'cat']
+    assert dog.norm_ == 'do'
+    assert cat.norm_ == 'ca'
+
+    bdata = pickle.dumps(vocab)
+    unpickled = pickle.loads(bdata)
+
+    assert unpickled[u'dog'].orth == dog.orth
+    assert unpickled[u'cat'].orth == cat.orth
+    assert unpickled[u'dog'].norm == dog.norm
+    assert unpickled[u'cat'].norm == cat.norm
+    dog_ = unpickled[u'dog']
+    cat_ = unpickled[u'cat']
+    assert dog_.norm != cat_.norm