[DAFFODIL-2859] dfdl:textNumberFormat "#.##" unparses 0.12 as "0.12" but should be ".12"

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: 3.5.0
• Fix Version/s: 3.6.0
• Component/s: ICU
• Assignee: Mike Beckerle
• Reporter: Mike Beckerle
• Created: 27/Oct/23 20:44
• Updated: 01/Nov/23 10:43
• Resolved: 30/Oct/23 19:02

Description

Due to ICU bug

 
https://unicode-org.atlassian.net/browse/ICU-22558
 
dfdl:textNumberPattern strings with # only, and no digits before the decimal point still end up creating a 0 digit before the decimal point.
 
For example "#.##" should format 0.12 as ".12" without a leading zero. 
 
This could be worked around in daffodil code by detecting when to call the `DecimalFormat.setMinimumIntegerDigits(0)` on the number format object. 
This requires a minor analysis of the ICU number pattern.