#72 misleading failure when specifying a non-schema URI

[Peter A. Bigot]

The following invocation, which improperly references a directory containing schema rather than a schema, produces a failure:

    assert tns is not None

that is not helpful.

pyxbgen \
    -u http://www.aixm.aero/gallery/content/public/schema/5.0/ISO_19136_Schemas/ \
    -u b.xsd -m b

[Peter A. Bigot]

• status changed from new to closed
• resolution set to fixed

The problem is that the URI content is HTML, and gets successfully parsed as XML, but the resulting tree is not an XML schema document.

As of [4872a28a0b20], will raise a SchemaValidationError.