Update Japanese tokenizer config and add serialization (#5562)

* Use `config` dict for tokenizer settings
* Add serialization of split mode setting
* Add tests for tokenizer split modes and serialization of split mode
setting

Based on #5561

spacy/lang/ja/__init__.py

@@ -1,7 +1,8 @@
 # encoding: utf8
 from __future__ import unicode_literals, print_function
 
-from collections import namedtuple
+import srsly
+from collections import namedtuple, OrderedDict
 
 from .stop_words import STOP_WORDS
 from .syntax_iterators import SYNTAX_ITERATORS
@@ -10,12 +11,13 @@ from .tag_orth_map import TAG_ORTH_MAP
 from .tag_bigram_map import TAG_BIGRAM_MAP
 from ...attrs import LANG
 from ...compat import copy_reg
+from ...errors import Errors
 from ...language import Language
 from ...symbols import POS
 from ...tokens import Doc
 from ...util import DummyTokenizer
+from ... import util
 
-from ...errors import Errors
 
 # Hold the attributes we need with convenient names
 DetailedToken = namedtuple("DetailedToken", ["surface", "pos", "lemma"])
@@ -26,14 +28,20 @@ DummyNode = namedtuple("DummyNode", ["surface", "pos", "lemma"])
 DummySpace = DummyNode(" ", " ", " ")
 
 
-def try_sudachi_import():
+def try_sudachi_import(split_mode="A"):
     """SudachiPy is required for Japanese support, so check for it.
-    It it's not available blow up and explain how to fix it."""
+    It it's not available blow up and explain how to fix it.
+    split_mode should be one of these values: "A", "B", "C", None->"A"."""
     try:
         from sudachipy import dictionary, tokenizer
-
+        split_mode = {
+            None: tokenizer.Tokenizer.SplitMode.A,
+            "A": tokenizer.Tokenizer.SplitMode.A,
+            "B": tokenizer.Tokenizer.SplitMode.B,
+            "C": tokenizer.Tokenizer.SplitMode.C,
+        }[split_mode]
         tok = dictionary.Dictionary().create(
-            mode=tokenizer.Tokenizer.SplitMode.A
+            mode=split_mode
         )
         return tok
     except ImportError:
@@ -164,9 +172,10 @@ def get_words_lemmas_tags_spaces(dtokens, text, gap_tag=("空白", "")):
 
 
 class JapaneseTokenizer(DummyTokenizer):
-    def __init__(self, cls, nlp=None):
+    def __init__(self, cls, nlp=None, config={}):
         self.vocab = nlp.vocab if nlp is not None else cls.create_vocab(nlp)
-        self.tokenizer = try_sudachi_import()
+        self.split_mode = config.get("split_mode", None)
+        self.tokenizer = try_sudachi_import(self.split_mode)
 
     def __call__(self, text):
         dtokens = get_dtokens(self.tokenizer, text)
@@ -193,6 +202,54 @@ class JapaneseTokenizer(DummyTokenizer):
         separate_sentences(doc)
         return doc
 
+    def _get_config(self):
+        config = OrderedDict(
+            (
+                ("split_mode", self.split_mode),
+            )
+        )
+        return config
+
+    def _set_config(self, config={}):
+        self.split_mode = config.get("split_mode", None)
+
+    def to_bytes(self, **kwargs):
+        serializers = OrderedDict(
+            (
+                ("cfg", lambda: srsly.json_dumps(self._get_config())),
+            )
+        )
+        return util.to_bytes(serializers, [])
+
+    def from_bytes(self, data, **kwargs):
+        deserializers = OrderedDict(
+            (
+                ("cfg", lambda b: self._set_config(srsly.json_loads(b))),
+            )
+        )
+        util.from_bytes(data, deserializers, [])
+        self.tokenizer = try_sudachi_import(self.split_mode)
+        return self
+
+    def to_disk(self, path, **kwargs):
+        path = util.ensure_path(path)
+        serializers = OrderedDict(
+            (
+                ("cfg", lambda p: srsly.write_json(p, self._get_config())),
+            )
+        )
+        return util.to_disk(path, serializers, [])
+
+    def from_disk(self, path, **kwargs):
+        path = util.ensure_path(path)
+        serializers = OrderedDict(
+            (
+                ("cfg", lambda p: self._set_config(srsly.read_json(p))),
+            )
+        )
+        util.from_disk(path, serializers, [])
+        self.tokenizer = try_sudachi_import(self.split_mode)
+
 
 class JapaneseDefaults(Language.Defaults):
     lex_attr_getters = dict(Language.Defaults.lex_attr_getters)
@@ -203,8 +260,8 @@ class JapaneseDefaults(Language.Defaults):
     writing_system = {"direction": "ltr", "has_case": False, "has_letters": False}
 
     @classmethod
-    def create_tokenizer(cls, nlp=None):
-        return JapaneseTokenizer(cls, nlp)
+    def create_tokenizer(cls, nlp=None, config={}):
+        return JapaneseTokenizer(cls, nlp, config)
 
 
 class Japanese(Language):

spacy/tests/lang/ja/test_serialize.py

@@ -0,0 +1,37 @@
+# coding: utf-8
+from __future__ import unicode_literals
+
+import pytest
+from spacy.lang.ja import Japanese
+from ...util import make_tempdir
+
+
+def test_ja_tokenizer_serialize(ja_tokenizer):
+    tokenizer_bytes = ja_tokenizer.to_bytes()
+    nlp = Japanese()
+    nlp.tokenizer.from_bytes(tokenizer_bytes)
+    assert tokenizer_bytes == nlp.tokenizer.to_bytes()
+    assert nlp.tokenizer.split_mode == None
+
+    with make_tempdir() as d:
+        file_path = d / "tokenizer"
+        ja_tokenizer.to_disk(file_path)
+        nlp = Japanese()
+        nlp.tokenizer.from_disk(file_path)
+        assert tokenizer_bytes == nlp.tokenizer.to_bytes()
+        assert nlp.tokenizer.split_mode == None
+
+    # split mode is (de)serialized correctly
+    nlp = Japanese(meta={"tokenizer": {"config": {"split_mode": "B"}}})
+    nlp_r = Japanese()
+    nlp_bytes = nlp.to_bytes()
+    nlp_r.from_bytes(nlp_bytes)
+    assert nlp_bytes == nlp_r.to_bytes()
+    assert nlp_r.tokenizer.split_mode == "B"
+
+    with make_tempdir() as d:
+        nlp.to_disk(d)
+        nlp_r = Japanese()
+        nlp_r.from_disk(d)
+        assert nlp_bytes == nlp_r.to_bytes()
+        assert nlp_r.tokenizer.split_mode == "B"

spacy/tests/lang/ja/test_tokenizer.py

@@ -3,6 +3,8 @@ from __future__ import unicode_literals
 
 import pytest
 
+from ...tokenizer.test_naughty_strings import NAUGHTY_STRINGS
+from spacy.lang.ja import Japanese
 
 # fmt: off
 TOKENIZER_TESTS = [
@@ -55,21 +57,39 @@ def test_ja_tokenizer_pos(ja_tokenizer, text, expected_pos):
     pos = [token.pos_ for token in ja_tokenizer(text)]
     assert pos == expected_pos
 
+
 @pytest.mark.parametrize("text,expected_sents", SENTENCE_TESTS)
 def test_ja_tokenizer_pos(ja_tokenizer, text, expected_sents):
     sents = [str(sent) for sent in ja_tokenizer(text).sents]
     assert sents == expected_sents
 
 
-def test_extra_spaces(ja_tokenizer):
+def test_ja_tokenizer_extra_spaces(ja_tokenizer):
     # note: three spaces after "I"
     tokens = ja_tokenizer("I   like cheese.")
     assert tokens[1].orth_ == "  "
 
-from ...tokenizer.test_naughty_strings import NAUGHTY_STRINGS
 
 @pytest.mark.parametrize("text", NAUGHTY_STRINGS)
-def test_tokenizer_naughty_strings(ja_tokenizer, text):
+def test_ja_tokenizer_naughty_strings(ja_tokenizer, text):
     tokens = ja_tokenizer(text)
     assert tokens.text_with_ws == text
 
+
+@pytest.mark.parametrize("text,len_a,len_b,len_c",
+    [
+        ("選挙管理委員会", 4, 3, 1),
+        ("客室乗務員", 3, 2, 1),
+        ("労働者協同組合", 4, 3, 1),
+        ("機能性食品", 3, 2, 1),
+    ]
+)
+def test_ja_tokenizer_split_modes(ja_tokenizer, text, len_a, len_b, len_c):
+    nlp_a = Japanese(meta={"tokenizer": {"config": {"split_mode": "A"}}})
+    nlp_b = Japanese(meta={"tokenizer": {"config": {"split_mode": "B"}}})
+    nlp_c = Japanese(meta={"tokenizer": {"config": {"split_mode": "C"}}})
+
+    assert len(ja_tokenizer(text)) == len_a
+    assert len(nlp_a(text)) == len_a
+    assert len(nlp_b(text)) == len_b
+    assert len(nlp_c(text)) == len_c