nom-sql: Allow whitespace inside ROW values and some function calls

Previously, nom expected function arguments to appear immediately
after the opening parenthesis. As a result, queries with whitespace
before the first argument or after the last one would fail to parse.

This behavior also affected ROW value expressions.

This commit fixes both cases.

Fixes: REA-5237
Closes: #1488
Release-Note-Core: Make parser more flexible with whitespaces
  in function arguments and `IN` list values.
Change-Id: Id4d8a8961fa602cfd1583a54c517e0994f1911aa
Reviewed-on: https://gerrit.readyset.name/c/readyset/+/9195
Tested-by: Buildkite CI
Reviewed-by: Marcelo Altmann <marcelo@readyset.io>

Author: MohamedAbdeen-rs

logictests/functions.test

@@ -9,3 +9,8 @@ select x, COALESCE(y, 2) FROM t1;
 ----
 1
 2
+
+query I
+SELECT COUNT ( 1 ) FROM t1;
+----
+1

logictests/where_in.test

@@ -21,7 +21,7 @@ select sum(id) from t1 where value in (another, 2);
 3
 
 query I ok
-select max(id) from t1 where id not in (another, 2);
+select max(id) from t1 where id not in ( another, 2 );
 ----
 4
 

nom-sql/src/common.rs

@@ -107,7 +107,12 @@ fn agg_fx_args(
 ) -> impl Fn(LocatedSpan<&[u8]>) -> NomSqlResult<&[u8], (Expr, bool)> {
     move |i| {
         let (i, _) = whitespace0(i)?;
-        delimited(tag("("), agg_function_arguments(dialect), tag(")"))(i)
+        let (i, _) = tag("(")(i)?;
+        let (i, _) = whitespace0(i)?;
+        let (i, args) = agg_function_arguments(dialect)(i)?;
+        let (i, _) = whitespace0(i)?;
+        let (i, _) = tag(")")(i)?;
+        Ok((i, args))
     }
 }
 
@@ -281,6 +286,7 @@ fn substring(dialect: Dialect) -> impl Fn(LocatedSpan<&[u8]>) -> NomSqlResult<&[
         let (i, _) = alt((tag_no_case("substring"), tag_no_case("substr")))(i)?;
         let (i, _) = whitespace0(i)?;
         let (i, _) = tag("(")(i)?;
+        let (i, _) = whitespace0(i)?;
         let (i, string) = expression(dialect)(i)?;
         let (i, pos) = opt(preceded(
             tuple((whitespace1, tag_no_case("from"), whitespace1)),

nom-sql/src/expression.rs

@@ -792,6 +792,7 @@ fn row_expr_implicit(dialect: Dialect) -> impl Fn(LocatedSpan<&[u8]>) -> NomSqlR
     move |i| {
         // Implicit row exprs must have two or more elements
         let (i, _) = tag("(")(i)?;
+        let (i, _) = whitespace0(i)?;
         let (i, first_expr) = expression(dialect)(i)?;
         let (i, _) = ws_sep_comma(i)?;
         let (i, rest_exprs) = separated_list1(
@@ -801,6 +802,7 @@ fn row_expr_implicit(dialect: Dialect) -> impl Fn(LocatedSpan<&[u8]>) -> NomSqlR
                 map(bracketed_expr_list(dialect), Expr::Array),
             )),
         )(i)?;
+        let (i, _) = whitespace0(i)?;
         let (i, _) = tag(")")(i)?;
 
         let mut exprs = Vec::with_capacity(rest_exprs.len() + 1);