Method doc_function

src/sql-pretty/src/doc.rs:1399–1457

(&'a self, v: &'a Function<T>)

    }

    fn doc_function<'a, T: AstInfo>(&'a self, v: &'a Function<T>) -> RcDoc<'a> {
        match &v.args {
            FunctionArgs::Star => self.doc_display_pass(v),
            FunctionArgs::Args { args, order_by } => {
                if args.is_empty() {
                    // Nullary, don't allow newline between parens, so just delegate.
                    return self.doc_display_pass(v);
                }
                if v.filter.is_some() || v.over.is_some() || !order_by.is_empty() {
                    return self.doc_display(v, "function filter or over or order by");
                }
                let name_stable = v.name.to_ast_string_stable();
                let special = match name_stable.as_str() {
                    r#""extract""# if v.args.len() == Some(2) => true,
                    r#""position""# if v.args.len() == Some(2) => true,
                    _ => false,
                };
                if special {
                    return self.doc_display(v, "special function");
                }
                // Mirror the same carve-out as the `AstDisplay for Function`
                // impl: function names that clash with a keyword having its
                // own special-grammar parser form (`(Kw, LParen)` dispatch in
                // parse_prefix) must be quoted on emit, or the reparse goes
                // through the special grammar instead of a regular call. (The
                // `ANY`/`ALL`/`SOME` quantifier keywords are handled more
                // generally by `can_be_printed_bare`, since they're also unsafe
                // as bare identifiers.)
                let needs_quote = matches!(
                    name_stable.as_str(),
                    r#""array""#
                        | r#""coalesce""#
                        | r#""exists""#
                        | r#""extract""#
                        | r#""greatest""#
                        | r#""least""#
                        | r#""list""#
                        | r#""map""#
                        | r#""normalize""#
                        | r#""nullif""#
                        | r#""position""#
                        | r#""row""#
                        | r#""substring""#
                        | r#""trim""#
                );
                let printed_name = if needs_quote {
                    name_stable
                } else {
                    v.name.to_ast_string_simple()
                };
                let name = format!(
                    "{}({}",
                    printed_name,
                    if v.distinct { "DISTINCT " } else { "" }
                );
                bracket(name, comma_separate(|e| self.doc_expr(e), args), ")")
            }
        }