Number of words validator

src/collective/volto/formsupport/validation/custom_validators/WordsValidator.py

@@ -0,0 +1,47 @@
+import re
+
+from Products.validation.interfaces.IValidator import IValidator
+from zope.interface import implementer
+
+
+@implementer(IValidator)
+class WordsValidator:
+    def __init__(
+        self,
+        name,
+        title="",
+        description="",
+        words=0,
+        _internal_type="",
+    ):
+        """ "Unused properties are for default values and type information"""
+        self.name = name
+        self.title = title or name
+        self.description = description
+        self._internal_type = _internal_type
+        # Default values
+        self.words = words
+
+    def __call__(self, value="", *args, **kwargs):
+        words = kwargs.get("words", self.words)
+        words = int(words)
+        count = len(re.findall(r"\w+", value))
+
+        if self._internal_type == "max":
+            if not value:
+                return
+            if count > words:
+                # TODO: i18n
+                msg = f"Validation failed({self.name}): is more than {words} words long"
+                return msg
+        elif self._internal_type == "min":
+            if not value or count < words:
+                # TODO: i18n
+                msg = f"Validation failed({self.name}): is less than {words} words long"
+                return msg
+        elif self._internal_type == "test":
+            pass
+        else:
+            # TODO: i18n
+            msg = f"Validation failed({self.name}): Unknown words validator type"
+            return msg

src/collective/volto/formsupport/validation/custom_validators/__init__.py

@@ -1,7 +1,12 @@
 from collective.volto.formsupport.validation.custom_validators.CharactersValidator import (
     CharactersValidator,
 )
+from collective.volto.formsupport.validation.custom_validators.WordsValidator import (
+    WordsValidator,
+)
 
 maxCharacters = CharactersValidator("maxCharacters", _internal_type="max")
 minCharacters = CharactersValidator("minCharacters", _internal_type="min")
-custom_validators = [maxCharacters, minCharacters]
+maxWords = WordsValidator("maxWords", _internal_type="max")
+minWords = WordsValidator("minWords", _internal_type="min")
+custom_validators = [maxCharacters, minCharacters, maxWords, minWords]