Most likely you're getting tripped up by (weirdo?) whitespace or other stuff that renders identical in the terminal.

To better diagnose that, I would dump the output on failure in a way that makes the differences spottable:

my $res = $s->gets(13);
if( !is $res, "hello, world!", "puts() and gets() ok") {
    (my $s = $res) =~ s!([^\w])!sprintf '\\x%02x', ord($1)!ge;
    diag $s;
    ($s = "hello, world!") =~ s!([^\w])!sprintf '\\x%02x', ord($1)!ge;
    diag $s;
};

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In reply to Re: Unit test failing but "got" and "expected" are equal by Corion
in thread Unit test failing but "got" and "expected" are equal by stevieb

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