Curiosity in start2RefS2.shex

[hsolbrig]

https://github.com/shexSpec/shexTest/blob/master/schemas/start2RefS2.shex has no reference to "p1":

start=@<http://a.example/S2>
<http://a.example/S2> {
   <http://a.example/p2> .
}

yet the https://github.com/shexSpec/shexTest/blob/master/schemas/start2RefS2.json and https://github.com/shexSpec/shexTest/blob/master/schemas/start2RefS2.ttl show one:

{ "@context": "http://www.w3.org/ns/shex.jsonld", "type": "Schema",
  "start": "http://a.example/S2",
  "shapes": [
    { "id": "http://a.example/S2", "type": "Shape", "expression": {
        "type": "TripleConstraint", "predicate": "http://a.example/p1" } }
  ] }

PREFIX sx: <http://www.w3.org/ns/shex#>

[] a sx:Schema ;
  sx:start <http://a.example/S2> ;
  sx:shapes <http://a.example/S2> .
    <http://a.example/S2> a sx:Shape ; sx:expression [
        a sx:TripleConstraint ; sx:predicate <http://a.example/p1> ] .

How can this happen and why does it pass existing unit tests?

[ericprud]

grammar has rev'd since this comment