[DAFFODIL-2363] pattern facet can't use  notation. Makes validating NUL very hard.

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.7.0
• Fix Version/s: 3.0.0
• Component/s: Back End
• Labels: beginner
• Assignee: Mike Beckerle
• Reporter: Mike Beckerle
• Created: 10/Jul/20 00:58
• Updated: 17/Nov/20 22:01
• Resolved: 21/Oct/20 18:41

Description

See test_nulPattern1.

This bug is a real pain in the neck.

I want to capture NUL padding regions and insure they are all NUL.

These come through to XML as These U+E000 characters. I need to insure that the string contains only those.

So I'd like to use a

<xs:simpleType name="allNULStringType>
  <xs:restriction base="xs:string">
     <xs:pattern value="&#xE000;*"/>
  </xs:restriction>
</xs:simpleType>

I consider this data well-formed (should parse) even if other bytes are there that aren't NUL, but such data is invalid. So I want the facet to check for all NUL chars (or these E000 things that Daffodil puts in XML because XML can't contain actual NUL chars).

The test fails with

org.apache.daffodil.tdml.TDMLExceptionImpl: (Implementation: daffodil) Validation errors found where none were expected by the test case.
Validation Error: ex:foo failed facet checks due to: facet pattern(s): *

If github does the right thing that pattern will look like the E000 box char and *.