Sorry to be dense, but what is $obj in your example?

When I read

my $test = DumpTable(...
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I got confused and thought that was the Text::ASCIITable constructor. Of course, that's not the case, so what I said doesn't apply.

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Please avoid

my ... for ...;
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It straddles edge cases in Perl. my ... if ...; is not allowed, for example, and it's not clear what your code does.

May I recommend

my $table = ( $t->find_by_tag_name('table') )[-1];
return DumpTable($table);
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If the find only returns one table, you can also use

my ($table) = $t->find_by_tag_name('table');
return DumpTable($table);
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