Quote columnrefs

[avinoamr]

Column refs could contain reserved keywords when parsed, like a column called "user", unlike the user keyword which is parsed into the current_user() function call. The deparse algorithm disregards this distinction by turning the column into the function call incorrectly.

For example, in the following query:

SELECT "user" FROM users

The "users" target list would be correctly parsed into

{
    "COLUMNREF": {
        "fields": [ "users" ]
    }
}

But deparsing this structure results in the following, incorrect query where user is a reserved keyword.:

SELECT user FROM users

This is fixed here by quoting all columnrefs.

[lfittl]

Good point - I think you are correct that we should simply quote all column refs to be on the safe side.

Could you update the tests to reflect this as well? (see failing Travis CI build)

Thanks for contributing! :)

[avinoamr]

@lfittl Done.

[lfittl]

@avinoamr Thanks, I know that was quite some more work, appreciate it!