Does XML::SemanticDiff only compare two files line by line in same location. Small test below indicates that two exact lines for DBUS in file are not detected. DBUS reported as rogue element.

#!/bin/perl
use strict;
use warnings;
my $file = 'xml1.xml';
my $file2 = 'xml2.xml';
my $h = Myclass->new;
# use XML::Parser;
use XML::SemanticDiff;
my $diff =  XML::SemanticDiff->new(diffhandler => $h, keepdata => 1);
$diff->compare($file, $file2);
package Myclass;
use Data::Dumper;
sub new { bless {}, shift }

sub attribute_value
{
  my ($self, $attr_name, $element, $to_props, $from_props) = @_;
  print "\n\nattribute value\n";
  print Dumper($self, $attr_name, $element, $to_props, $from_props);
}

sub rogue_element
{
  my ( $self, $name, $props ) = @_;
  print "\n\nrogue element\n";
  print Dumper($self, $name, $props);
}
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Sample xml1 file

<root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noName
+spaceSchemaLocation="panoply.xsd">
  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public"/>
    <all_members name="DBUS" protection="public"/>
  </classes>
</root>
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Sample xml2 file

<root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noName
+spaceSchemaLocation="panoply.xsd">
  <classes name="Panoply::AccessLogic">
    <all_members name="accessLogic" protection="public"/>
    <all_members name="APR" protection="public"/>
    <all_members name="DBUS" protection="public"/>
  </classes>
</root>
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