OK try

#!perl
use strict;
use Data::Dumper;
my $str = 'eab12345 a b c id=00000 x= pgrp=abc=defgh groups=abcdefgh a
+nd more roles=';
my @f = split / (\w+=)/,$str;

my @array = ();
while (@f){
  my $k = shift @f;
  if ($k =~ /=$/){
    my $v = shift @f;
    push @array,"$k$v";
  } else {
    # key no equal
    push @array,"$_=" for split /\s+/,$k;
  }
}
print Dumper \@array;
[download]