wrong encoding of zero value in numeric

[Standing-Man]

    #[test]
    fn numberic_zero() {
        let decimal_zero = Decimal::from(0);

        let mut binary_result = BytesMut::new();
        decimal_zero.to_sql(&Type::ANY, &mut binary_result).unwrap();
        
        assert_eq!(binary_result.len(), 10);
        assert_eq!(&binary_result[..], &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);
    }

But I’m getting the following failed test output, as shown below:

thread 'postgres::driver::test::numberic_zero' (13608077) panicked at src/postgres/driver.rs:477:9:
assertion `left == right` failed
  left: [0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
 right: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

Detail

As shown in https://github.com/postgres/postgres/blob/master/src/backend/utils/adt/numeric.c

/*
 * zero_var() -
 *
 *	Set a variable to ZERO.
 *	Note: its dscale is not touched.
 */
static void
zero_var(NumericVar *var)
{
	digitbuf_free(var->buf);
	var->buf = NULL;
	var->digits = NULL;
	var->ndigits = 0;
	var->weight = 0;			/* by convention; doesn't really matter */
	var->sign = NUMERIC_POS;	/* anything but NAN... */
}

tempdb=# select numeric_send(0);
    numeric_send    
--------------------
 \x0000000000000000
(1 row)

[Tony-Samuels]

It looks like all our tests use Type::Numeric. I'll need to play around with this a little and work out how the postgres library works with the types. I also wonder what this roundtrips back as.