Postgres support: parse function body (i.e. not as string)

[joelmukuthu]

Currently, function bodies are parsed as string literals which means that when formatting the code via prettier-plugin-sql-cst, the function bodies are left as is. I work on a project with quite a few functions where we would benefit a great deal from having the function bodies be formatted. Would you be up for adding support for it? :)

I'd also be interested in working on this, if this could be considered a good-first-issue.

And thanks for your continued work on this project! :)

[nene]

Thanks for the interest.

This feature is sort of in the plans... though not quite as you're suggesting it:

• no I have no plans of implementing the parsing of function body string inside sql-parser-cst.
• yes the parsing of function body can be done, but at the prettier-plugin level.

To clarify. This already works for BigQuery functions/procedures which can be written in JavaScript or Python. For example:

CREATE FUNCTION gen_random()
RETURNS FLOAT64
LANGUAGE js
AS r'''
  if (true) {
    return Math.random() * 2;
  }
'''

Likewise with PostgreSQL there are also different languages that the function body can be written in:

• SQL
• pl/pgsql
• pl/python
• ...

For start we could make the formatter work with SQL. This I guess can be achieved relatively easily by following the existing implementation of JS and Python support in function bodies.

But really the most common use case is LANGUAGE plpgsql, and for that we'll first need to implement parser of the plpgsql language.

[joelmukuthu]

Thanks for the response! And thanks a lot for giving some insight into how this all works, it's great to know how it all comes together.

I'll find some time in the coming weeks to look into making the formatter work with SQL on the prettier plugin -- that'll actually affect the majority of functions in the project I work on. In the meantime, feel free to close this issue since it's scope is much larger. I can create another one in the prettier plugin with the redefined scope.