Unexpected Results when Using IN for Floating-Point

[suyZhong]

Consider the test case below. It is unexpected that the second query returns 1 (true). If it is intended, the third query should return the row in the table as well. I guess there might be some optimization in the filter that accidently corrects the expression.

CREATE TABLE t1(c0 INTEGER, PRIMARY KEY(c0));
INSERT INTO t1 (c0) VALUES (1);

SELECT * FROM t1; -- 1
SELECT  (c0 IN (NULL, 0.8)) FROM t1; -- 1 (Unexpected)
SELECT * FROM t1 WHERE (c0 IN (NULL, 0.8)); -- Empty

Besides, the result of the query is different from MySQL.

-- In Dolt:
SELECT  (1 IN (NULL, 0.8)); -- 1
-- In MySQL:
SELECT  (1 IN (NULL, 0.8)); -- NULL

I also noticed that, if we removed the PK constraint, the result of the third query would be 1 (true), which matches the result of the second query, but is different from MySQL.

CREATE TABLE t1(c0 INTEGER);
INSERT INTO t1 (c0) VALUES (1);

SELECT * FROM t1; -- 1
SELECT  (c0 IN ((NULL), 0.8)) FROM t1; -- 1 (Unexpected)
SELECT * FROM t1 WHERE (c0 IN ((NULL), 0.8)); -- 1

I originally find this by building dolt from source code a7447ba. I found I couldn't reproduce the first issue in 1.29.0, but the discrepancy issue still exists.

Kindly inform me if it is caused by distinct reasons.