[1.10.X] Fix field regex with StrictStr type annotation

[sisp]

There's an inconsistency between constr(...) and ConstrainedStr, which is the base class of StrictStr, with regard to the expected type of the regex argument/attribute which causes a field of type StrictStr with a regex constraint specified via the Field(...) class to raise an error:

File "pydantic/main.py", line 340, in pydantic.main.BaseModel.__init__
File "pydantic/main.py", line 1076, in pydantic.main.validate_model
File "pydantic/fields.py", line 884, in pydantic.fields.ModelField.validate
File "pydantic/fields.py", line 1101, in pydantic.fields.ModelField._validate_singleton
File "pydantic/fields.py", line 1148, in pydantic.fields.ModelField._apply_validators
File "pydantic/class_validators.py", line 318, in pydantic.class_validators._generic_validator_basic.lambda13
File "pydantic/types.py", line 433, in pydantic.types.ConstrainedStr.validate
AttributeError: 'str' object has no attribute 'match'

I've fixed this inconsistency in a backwards compatible way by extending the type of regex in ConstrainedStr to also support a str value in addition to Pattern[str].

I hope this fix will be considered despite the ongoing efforts towards Pydantic v2. 🙂

[samuelcolvin]

otherwise happy to accept this.

[samuelcolvin]

I'm afraid this might be slow since the compiled regex might not be cached.

Better to do the following which I think should work in both cases

Suggested change

	regex = cls._regex()
	if regex:
	if not regex.match(value):
	if cls.regex:
	if not re.match(cls.regex, value):

[samuelcolvin]

you'll therefore still need an isinstance check here.

[sisp]

@samuelcolvin Thanks for your review feedback! I think I've made the changes accordingly which should improve regex caching. Happy to receive your feedback again. 🙂

[samuelcolvin]

LGTM.

@hramezani please review and check you're happy with this.

[hramezani]

LGTM 👍

Thanks @sisp

[samuelcolvin]

thanks so much for this.

[sisp]

Sure thing, thanks for the review parallel to all the v2 dev work! Can't wait to see v2 and all its improvements! 😉