Expose early_update option

Also fix a small bug -- C fields of Beam could not be accessed because
it was passed as a Python object.

spacy/pipeline/_parser_internals/_beam_utils.pyx

@@ -207,7 +207,7 @@ def update_beam(TransitionSystem moves, states, golds, model, int width, beam_de
     return loss
 
 
-def _lowest_score_has_cost(beam: Beam) -> bool:
+def _lowest_score_has_cost(Beam beam) -> bool:
     """Check whether the lowest-scoring candidate
     in a parse is marked as non-gold, i.e. it has a cost
     > 0."""

spacy/pipeline/dep_parser.pyx

@@ -130,6 +130,7 @@ def make_parser(
         "beam_width": 8,
         "beam_density": 0.01,
         "beam_update_prob": 0.5,
+        "early_update": False,
         "moves": None,
         "update_with_oracle_cut_size": 100,
         "learn_tokens": False,
@@ -157,6 +158,7 @@ def make_beam_parser(
     beam_width: int,
     beam_density: float,
     beam_update_prob: float,
+    early_update: bool,
     scorer: Optional[Callable],
 ):
     """Create a transition-based DependencyParser component that uses beam-search.
@@ -209,6 +211,7 @@ def make_beam_parser(
         beam_width=beam_width,
         beam_density=beam_density,
         beam_update_prob=beam_update_prob,
+        early_update=early_update,
         multitasks=[],
         learn_tokens=learn_tokens,
         min_action_freq=min_action_freq,
@@ -269,6 +272,7 @@ cdef class DependencyParser(Parser):
         beam_width=1,
         beam_density=0.0,
         beam_update_prob=0.0,
+        early_update=False,
         multitasks=tuple(),
         incorrect_spans_key=None,
         scorer=parser_score,
@@ -286,6 +290,7 @@ cdef class DependencyParser(Parser):
             beam_width=beam_width,
             beam_density=beam_density,
             beam_update_prob=beam_update_prob,
+            early_update=early_update,
             multitasks=multitasks,
             incorrect_spans_key=incorrect_spans_key,
             scorer=scorer,

spacy/pipeline/transition_parser.pyx

@@ -51,6 +51,7 @@ cdef class Parser(TrainablePipe):
         beam_width=1,
         beam_density=0.0,
         beam_update_prob=0.0,
+        early_update=False,
         multitasks=tuple(),
         incorrect_spans_key=None,
         scorer=None,
@@ -103,6 +104,7 @@ cdef class Parser(TrainablePipe):
             "beam_width": beam_width,
             "beam_density": beam_density,
             "beam_update_prob": beam_update_prob,
+            "early_update": early_update,
             "incorrect_spans_key": incorrect_spans_key
         }
         if moves is None:
@@ -387,7 +389,8 @@ cdef class Parser(TrainablePipe):
                 beam_width=self.cfg["beam_width"],
                 sgd=sgd,
                 losses=losses,
-                beam_density=self.cfg["beam_density"]
+                beam_density=self.cfg["beam_density"],
+                early_update=self.cfg["early_update"]
             )
         max_moves = self.cfg["update_with_oracle_cut_size"]
         if max_moves >= 1:
@@ -485,7 +488,8 @@ cdef class Parser(TrainablePipe):
         return losses
 
     def update_beam(self, examples, *, beam_width,
-            drop=0., sgd=None, losses=None, beam_density=0.0):
+                    drop=0., sgd=None, losses=None, beam_density=0.0,
+                    early_update=False):
         states, golds, _ = self.moves.init_gold_batch(examples)
         if not states:
             return losses
@@ -499,6 +503,7 @@ cdef class Parser(TrainablePipe):
             model,
             beam_width,
             beam_density=beam_density,
+            early_update=early_update,
         )
         losses[self.name] += loss
         backprop_tok2vec(golds)