transpile doesn't work for date_trunc from duckdb to spark/databricks

[xinglin-zhao]

Hi there, i have an issue with transpile. It cannot work for date_trunc from duckdb to spark/databricks, see below:

from pypika import CustomFunction
from pypika.functions import Timestamp
from sqlglot import transpile
from datetime import datetime


DateTrunc = CustomFunction("date_trunc", ["part", "timestamp"])
# duckdb format https://duckdb.org/docs/archive/0.2.8/sql/functions/timestamp
query = DateTrunc("hour", Timestamp(datetime.now())).get_sql(dialect="duckdb")
print(query)

spark_sql = transpile(query, read="duckdb", write="databricks", pretty=True)

print(spark_sql)

The output is

date_trunc('hour',TIMESTAMP('2023-07-01T00:29:36.860678'))
["TRUNC(TIMESTAMP('2023-07-01T00:29:36.860678'), 'hour')"]

expecting the databricks sql output be something like this date_trunc('hour',TIMESTAMP('2023-07-01T00:29:36.860678')), see doc https://docs.databricks.com/sql/language-manual/functions/date_trunc.html