From 16aa092fb5cffb5ec7079951ea0c04cb96733b3e Mon Sep 17 00:00:00 2001
From: Ines Montani <ines@ines.io>
Date: Sat, 21 Sep 2019 14:37:06 +0200
Subject: [PATCH] Improve Morphology errors (#4314)

* Improve Morphology errors

* Also clean up some other errors

* Update errors.py
---
 spacy/errors.py                    | 7 +++++++
 spacy/morphology.pyx               | 6 +++---
 spacy/syntax/transition_system.pyx | 3 +--
 spacy/util.py                      | 2 +-
 4 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/spacy/errors.py b/spacy/errors.py
index b03bd6d23fd..a6b199a5098 100644
--- a/spacy/errors.py
+++ b/spacy/errors.py
@@ -469,6 +469,13 @@ class Errors(object):
             "that case.")
     E166 = ("Can only merge DocBins with the same pre-defined attributes.\n"
             "Current DocBin: {current}\nOther DocBin: {other}")
+    E167 = ("Unknown morphological feature: '{feat}' ({feat_id}). This can "
+            "happen if the tagger was trained with a different set of "
+            "morphological features. If you're using a pre-trained model, make "
+            "sure that your models are up to date:\npython -m spacy validate")
+    E168 = ("Unknown field: {field}")
+    E169 = ("Can't find module: {module}")
+    E170 = ("Cannot apply transition {name}: invalid for the current state.")
 
 
 @add_codes
diff --git a/spacy/morphology.pyx b/spacy/morphology.pyx
index 190ca8d00a6..c146094a900 100644
--- a/spacy/morphology.pyx
+++ b/spacy/morphology.pyx
@@ -197,7 +197,7 @@ cdef class Morphology:
         cdef attr_t feature
         for feature in features:
             if feature != 0 and feature not in self._feat_map.id2feat:
-                raise KeyError("Unknown feature: %s" % self.strings[feature])
+                raise ValueError(Errors.E167.format(feat=self.strings[feature], feat_id=feature))
         cdef MorphAnalysisC tag
         tag = create_rich_tag(features)
         cdef hash_t key = self.insert(tag)
@@ -531,7 +531,7 @@ cdef attr_t get_field(const MorphAnalysisC* tag, int field_id) nogil:
     elif field == Field_VerbType:
         return tag.verb_type
     else:
-        raise ValueError("Unknown field: (%d)" % field_id)
+        raise ValueError(Errors.E168.format(field=field_id))
 
 
 cdef int check_feature(const MorphAnalysisC* tag, attr_t feature) nogil:
@@ -726,7 +726,7 @@ cdef int set_feature(MorphAnalysisC* tag,
     elif field == Field_VerbType:
         tag.verb_type = value_
     else:
-        raise ValueError("Unknown feature: %s (%d)" % (FEATURE_NAMES.get(feature), feature))
+        raise ValueError(Errors.E167.format(field=FEATURE_NAMES.get(feature), field_id=feature))
 
 
 FIELDS = {
diff --git a/spacy/syntax/transition_system.pyx b/spacy/syntax/transition_system.pyx
index 523cd66994c..fede704b536 100644
--- a/spacy/syntax/transition_system.pyx
+++ b/spacy/syntax/transition_system.pyx
@@ -96,8 +96,7 @@ cdef class TransitionSystem:
 
     def apply_transition(self, StateClass state, name):
         if not self.is_valid(state, name):
-            raise ValueError(
-                "Cannot apply transition {name}: invalid for the current state.".format(name=name))
+            raise ValueError(Errors.E170.format(name=name))
         action = self.lookup_transition(name)
         action.do(state.c, action.label)
 
diff --git a/spacy/util.py b/spacy/util.py
index e88d664524f..dbe965392c7 100644
--- a/spacy/util.py
+++ b/spacy/util.py
@@ -136,7 +136,7 @@ def load_language_data(path):
 
 def get_module_path(module):
     if not hasattr(module, "__module__"):
-        raise ValueError("Can't find module {}".format(repr(module)))
+        raise ValueError(Errors.E169.format(module=repr(module)))
     return Path(sys.modules[module.__module__].__file__).parent