Validating an instance with an unknown $schema should error

[Julian]

In validator_for, and transitively in validate, providing an instance whose $schema isn't one of the known metaschemas should error, not use the latest supported version.

It looks like that was my intention originally, judging by the docstring, but the code and tests use the default in all cases.

This will unfortunately not be changeable immediately, it'll need a deprecation period first, so step one is to do that.

[Julian]

About the deprecation? you mean add warnings when a schema is not found

but use the latest anyway? why not just raise an Exception since v3 is going to be a major bump Thanks for asking that, it's a subtle thing that a lot of us developers get wrong :) So, the rationale there is that semantic versioning tells you what to do *when* you need to make a backwards incompatible change. It's a signaling mechanism. It isn't an excuse to just break things just because you're changing a number :). People very well might be relying on those things, and just because you bumped a version doesn't change that you're going to break their stuff. So everything still needs a deprecation period where things warn, so that people are given a chance to fix their code *before* things break on them all at once. (This was Py3's major mistake, which we've paid a lot for over the years, so it's a lesson we've now learned the hard way :P). Hope that makes sense, but lemme know if that needs some more clarification.

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On Thu, Nov 1, 2018 at 6:26 PM Opemipo ***@***.***> wrote: About the deprecation? you mean add warnings when a schema is not found but use the latest anyway? why not just raise an Exception since v3 is going to be a major bump — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#460 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAUIXraO_7U1Q1yBdQeb72yyc6cU9Ud4ks5uq3UFgaJpZM4WnHUx> .

[opethe1st]

Sorry deleted my comment after I realized that you actually explained and answered here . I just didnt read it properly. Definitely makes sense, need to warn before removing stuff.