Cardinality contraint issue when omitting sh:maxCount in a closed shape

[herminiogg]

Given the following input:

@prefix schema: <http://schema.org/> .
@prefix ex:    <http://example.com/> .
@prefix dbr:   <http://dbpedia.org/resource/> .
@prefix rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix xsd:   <http://www.w3.org/2001/XMLSchema#> .

ex:4    a                       ex:Film ;
        ex:screenwritter        dbr:Jonathan_Nolan , dbr:Christopher_Nolan ;
        ex:year                 dbr:2006 ;
        schema:countryOfOrigin  dbr:USA ;
        schema:director         dbr:Christopher_Nolan ;
        schema:musicBy          dbr:David_Julyan ;
        schema:name             "The Prestige" .

ex:3    a                       ex:Film ;
        ex:screenwritter        dbr:Christopher_Nolan ;
        ex:year                 dbr:2010 ;
        schema:countryOfOrigin  dbr:USA ;
        schema:director         dbr:Christopher_Nolan ;
        schema:musicBy          dbr:Hans_Zimmer ;
        schema:name             "Inception" .

ex:2    a                       ex:Film ;
        ex:screenwritter        dbr:Jonathan_Nolan , dbr:Christopher_Nolan ;
        ex:year                 dbr:2014 ;
        schema:countryOfOrigin  dbr:USA ;
        schema:director         dbr:Christopher_Nolan ;
        schema:musicBy          dbr:Hans_Zimmer ;
        schema:name             "Interstellar" .

ex:1    a                       ex:Film ;
        ex:screenwritter        dbr:Christopher_Nolan ;
        ex:year                 dbr:2017 ;
        schema:countryOfOrigin  dbr:USA ;
        schema:director         dbr:Christopher_Nolan ;
        schema:musicBy          dbr:Hans_Zimmer ;
        schema:name             "Dunkirk" .

and the following SHACL shape (using closed shapes):

@prefix schema: <http://schema.org/> .
@prefix ex:    <http://example.com/> .
@prefix rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix sh:    <http://www.w3.org/ns/shacl#> .
@prefix dbr:   <http://dbpedia.org/resource/> .
@prefix xsd:   <http://www.w3.org/2001/XMLSchema#> .

ex:Film  a              sh:NodeShape ;
        sh:closed       true ;
        sh:property     [ sh:maxCount  1 ;
                          sh:minCount  1 ;
                          sh:nodeKind  sh:IRI ;
                          sh:path      schema:countryOfOrigin
                        ] ;
        sh:property     [ sh:in    ( ex:Film ) ;
                          sh:path  rdf:type
                        ] ;
        sh:property     [ sh:maxCount  1 ;
                          sh:minCount  1 ;
                          sh:nodeKind  sh:IRI ;
                          sh:path      ex:year
                        ] ;
        sh:property     [ sh:maxCount  1 ;
                          sh:minCount  1 ;
                          sh:nodeKind  sh:IRI ;
                          sh:path      schema:director
                        ] ;
        sh:property     [ sh:maxCount  1 ;
                          sh:minCount  1 ;
                          sh:nodeKind  sh:IRI ;
                          sh:path      schema:musicBy
                        ] ;
        sh:property     [ sh:datatype  xsd:string ;
                          sh:maxCount  1 ;
                          sh:minCount  1 ;
                          sh:path      schema:name
                        ] ;
        sh:property     [ sh:minCount  1 ;
                          sh:nodeKind  sh:IRI ;
                          sh:path      ex:screenwritter
                        ] ;
        sh:targetClass  ex:Film .

It seems that shaclex validator is taking the default ShEx cardinality values (i.e., 1 for max and min) instead of SHACL ones. When I tried this example on RDFShape I reached a satisfactory validation with JenaSHACL and SHACL_TQ validators; however, when I used shaclex validator it complains about the cardinality of ex:screenwritter property.

I looked into the SHACL specification and it was not clear for me which is the default cardinality behaviour, so it would be interesting to clarify this. Although, I assume this as an error due to the difference between this engine and the other two mentioned ones.