Out-of-order schemas

[gregsdennis]

I had an issue raised where someone put $defs at the beginning of their schema, and my solution didn't handle it properly.

In particular, my implementation failed to set the dialect from $schema before building the subschemas in the $defs, which meant they were built using the default dialect.

We should have some tests that ensure $schema is respected regardless of where it appears lexigraphically in the schema. (Of course, it needs to be at the root.)

[mwadams]

More generally, this falls under the "keyword ordering MUST be insignificant" banner.

[RishiByte]

I agree that keyword ordering should be irrelevant. Since JSON objects are unordered by nature, implementations shouldn't depend on the lexical position of keywords such as $schema, $defs, or $id.

Adding tests where $schema appears after $defs (and potentially after other keywords as well) would help catch implementations that accidentally process schemas sequentially instead of evaluating them according to the specification.