[chinmayajha]

RefResolver.walk only went into dict values, so subschemas in allOf, anyOf, oneOf and items arrays were never walked. An $id there was never registered, and a relative $ref there was not joined with the base URI of its parent $id:

import fastjsonschema

schema = {
    '$schema': 'http://json-schema.org/draft-07/schema',
    'allOf': [
        {'$ref': 'http://example.com/ref/if'},
        {'if': {'$id': 'http://example.com/ref/if', 'type': 'integer'}},
    ],
}
fastjsonschema.validate(schema, 12)
# tries to download http://example.com/ref/if

The walk now follows the keywords that hold subschemas and skips the data keywords (const, default, enum, examples). Before, a $ref inside a const or default value was rewritten to an absolute URI, so the const no longer matched its own value. _expand_refs in the generator skips the same keywords, so a $ref inside data is not resolved when building error messages.

With this, ref.json from the test suite passes for draft 06 and 07 and id.json passes for draft 04, 06 and 07, so I removed them from the ignore lists. I also added a test in tests/test_integration.py for a $ref inside const under a nested $id, which fails on master. The full suite passes and pylint is unchanged. CHANGELOG has entries under UNRELEASED.

[chinmayajha]

@horejsek could you approve the workflow runs and review this when you have a moment?