clickhouse: CAST fails in various scenarios

[pkit]

SELECT
    CAST(['hello'], 'Array(Enum8(\'hello\' = 1))') AS x,
    (1, CAST('hello', 'Enum8(\'hello\' = 1)')) AS y
FORMAT PrettyCompactNoEscapes

Expected AS after CAST. Line 2, Col: 19.
  SELECT
    CAST(['hello']🔻,🔻 'Array(Enum8(\'hello\' = 1))') AS x,
    (1, CAST('hello', 'Enum8(\'hello\' = 1)')) AS y
FORMAT Pre

SELECT
    k,
    groupArray(x) AS res1,
    toTypeName(res1),
    avg(x) AS res2,
    toTypeName(res2)
FROM
(
    SELECT
        1 AS k,
        arrayJoin([1, NULL, 2]) AS x
    UNION ALL
    SELECT
        2 AS k,
        CAST(arrayJoin([NULL, NULL]), 'Nullable(UInt8)') AS x
)
GROUP BY k
ORDER BY k ASC

Expected AS after CAST. Line 15, Col: 37.
  oin([1, NULL, 2]) AS x
    UNION ALL
    SELECT
        2 AS k,
        CAST(arrayJoin([NULL, NULL])🔻,🔻 'Nullable(UInt8)') AS x
)
GROUP BY k
ORDER BY k ASC

SELECT CAST(if(number = 999999, NULL, number), 'UInt64')
FROM system.numbers
LIMIT 10

Expected AS after CAST. Line 1, Col: 47.
  SELECT CAST(if(number = 999999, NULL, number)🔻,🔻 'UInt64')
FROM system.numbers
LIMIT 10

Docs: https://clickhouse.com/docs/en/sql-reference/functions/type-conversion-functions#castx-t