[DAFFODIL-1976] Incorrect creation of empty-string element

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.0
• Fix Version/s: 2.4.0
• Component/s: Back End, Compatibility
• Labels: ForInteroperabilityTest
• Assignee: Dave Thompson
• Reporter: Mike Beckerle
• Created: 02/Aug/18 17:11
• Updated: 20/May/21 12:34
• Resolved: 23/May/19 17:24

Description

Test "scenario1_7" was made "threePass" to get it to pass, but really it should be onePass, and the underlying Daffodil behavior needs to change.

Specifically, an empty <y/> element appears in the infoset from the first parse pass, and that element should NOT be present, as the element is optional, the content is zero-length, and the type is xs:string. This <y/> element should only be created if there is some empty value syntax defined by way of initiator/terminator/emptyValueDelimiterPolicy.

See the shouldRemoveZLStringHexBinaryValue method, which the code has wired to 'false' currently. Note that the parse must be attempted so that asserts/discriminators and setVars are executed.

Furthermore, note that this does NOT terminate the array, as it is not a processing error.

This test, and other tests that construct these empty 'y' elements should be corrected, and should not require threePass treatment from the TDML runner.