Problem

-- on Integrator 3.6.0, when the definition of the field is > 0, and when there is a mapping expression that valued the field to "" or to no value, the parser is no adding space / blank characters to match the minimum size of the field

-- on Integrator 3.7.3, when the definition of the field is > 0, and when there is a mapping expression that valued the field to "" or to no value, the parser pads the field with space / blank characters to match the minimum size of the field

-- example (look at the second field of the second ISA segment, it has a min definition 1 and has a mapping expression that sets the value to "")

result on Integrator 3.6.0 :

UNH+1'USH+7+SRN01+3++++1+ZH1+1:20170419:105232'USA+1:::48'USC+4: +3'USA+6:::10:1'UNT+6+1'

result on Integrator 3.7.3 :

UNH+1'USH+7+SRN01+3++++1+ZH1+1:20170419:105424'USA+1:::48'USC+4: +3'USA+6: ::10:1'UNT+6+1'

Resolution

* the behavior is valid on Integrator 3.7.3. It is not valid on Integrator 3.6.0 because the parser produces message not conform with the definition of the Bdoc

* for migration issues to 3.7.3, the environment CORE_DML_NO_EXTRA_SPACES can be used to get back to the previous behavior

add the line CORE_DML_NO_EXTRA_SPACES=true in $CORE_LOCAL/config/environment.dat

* another option is to set the value to "null" in the mapping expression for the field that causes the issue (possible in case the problem occurs on few fields)