* Fix missing root labels bug identified in Issue #57

spacy/syntax/arc_eager.pyx

@@ -88,9 +88,15 @@ cdef class ArcEager(TransitionSystem):
         t.get_cost = get_cost_funcs[move]
         return t
 
-    cdef int first_state(self, State* state) except -1:
+    cdef int initialize_state(self, State* state) except -1:
         push_stack(state)
 
+    cdef int finalize_state(self, State* state) except -1:
+        cdef int root_label = self.strings['ROOT']
+        for i in range(state.sent_len):
+            if state.sent[i].head == 0 and state.sent[i].dep == 0:
+                state.sent[i].dep = root_label
+
     cdef Transition best_valid(self, const weight_t* scores, const State* s) except *:
         cdef bint[N_MOVES] is_valid
         is_valid[SHIFT] = _can_shift(s)

spacy/syntax/ner.pyx

@@ -124,9 +124,6 @@ cdef class BiluoPushDown(TransitionSystem):
         t.get_cost = _get_cost
         return t
 
-    cdef int first_state(self, State* state) except -1:
-        pass
-
     cdef Transition best_valid(self, const weight_t* scores, const State* s) except *:
         cdef int best = -1
         cdef weight_t score = -90000

spacy/syntax/parser.pyx

@@ -83,15 +83,14 @@ cdef class GreedyParser:
         cdef int n_feats
         cdef Pool mem = Pool()
         cdef State* state = new_state(mem, tokens.data, tokens.length)
-        self.moves.first_state(state)
+        self.moves.initialize_state(state)
         cdef Transition guess
         while not is_final(state):
             fill_context(context, state)
             scores = self.model.score(context)
             guess = self.moves.best_valid(scores, state)
-            #print self.moves.move_name(guess.move, guess.label),
-            #print print_state(state, [w.orth_ for w in tokens])
             guess.do(&guess, state)
+        self.moves.finalize_state(state)
         tokens.set_parse(state.sent)
         return 0
 
@@ -99,7 +98,7 @@ cdef class GreedyParser:
         self.moves.preprocess_gold(gold)
         cdef Pool mem = Pool()
         cdef State* state = new_state(mem, tokens.data, tokens.length)
-        self.moves.first_state(state)
+        self.moves.initialize_state(state)
 
         cdef int cost
         cdef const Feature* feats
@@ -117,3 +116,4 @@ cdef class GreedyParser:
             self.model.update(context, guess.clas, best.clas, cost)
 
             guess.do(&guess, state)
+        self.moves.finalize_state(state)

spacy/syntax/transition_system.pxd

@@ -30,7 +30,8 @@ cdef class TransitionSystem:
     cdef const Transition* c
     cdef readonly int n_moves
 
-    cdef int first_state(self, State* state) except -1
+    cdef int initialize_state(self, State* state) except -1
+    cdef int finalize_state(self, State* state) except -1
 
     cdef int preprocess_gold(self, GoldParse gold) except -1
     

spacy/syntax/transition_system.pyx

@@ -26,8 +26,11 @@ cdef class TransitionSystem:
                 i += 1
         self.c = moves
 
-    cdef int first_state(self, State* state) except -1:
-        raise NotImplementedError
+    cdef int initialize_state(self, State* state) except -1:
+        pass
+
+    cdef int finalize_state(self, State* state) except -1:
+        pass
 
     cdef int preprocess_gold(self, GoldParse gold) except -1:
         raise NotImplementedError