Support redshift's columns definition list for system information functions (#769)

* parsing of redshift's column definition list for
pg_get_late_binding_view_cols
pg_get_cols
pg_get_grantee_by_iam_role
pg_get_iam_role_by_user

* Renamed ColsDefinition to TableAliasDefinition

added generic dialect

* Tests fixed

* Visitor for IdentPair

* Parsing redshift table alias based on indentifier and
parentheses instead of function name

* fix clippy

---------

Co-authored-by: Maciej Skrzypkowski <maciej.skrzypkowski@satoricyber.com>
Co-authored-by: Andrew Lamb <andrew@nerdnetworks.org>

src/parser.rs

@@ -5649,6 +5649,7 @@ impl<'a> Parser<'a> {
             } else {
                 None
             };
+            let columns_definition = self.parse_redshift_columns_definition_list()?;
             let alias = self.parse_optional_table_alias(keywords::RESERVED_FOR_TABLE_ALIAS)?;
             // MSSQL-specific table hints:
             let mut with_hints = vec![];
@@ -5665,11 +5666,56 @@ impl<'a> Parser<'a> {
                 name,
                 alias,
                 args,
+                columns_definition,
                 with_hints,
             })
         }
     }
 
+    fn parse_redshift_columns_definition_list(
+        &mut self,
+    ) -> Result<Option<TableAliasDefinition>, ParserError> {
+        if !dialect_of!(self is RedshiftSqlDialect | GenericDialect) {
+            return Ok(None);
+        }
+
+        if let Some(col_definition_list_name) = self.parse_optional_columns_definition_list_alias()
+        {
+            if self.consume_token(&Token::LParen) {
+                let names = self.parse_comma_separated(Parser::parse_ident_pair)?;
+                self.expect_token(&Token::RParen)?;
+                Ok(Some(TableAliasDefinition {
+                    name: col_definition_list_name,
+                    args: names,
+                }))
+            } else {
+                self.prev_token();
+                Ok(None)
+            }
+        } else {
+            Ok(None)
+        }
+    }
+
+    fn parse_optional_columns_definition_list_alias(&mut self) -> Option<Ident> {
+        match self.next_token().token {
+            Token::Word(w) if !keywords::RESERVED_FOR_TABLE_ALIAS.contains(&w.keyword) => {
+                Some(w.to_ident())
+            }
+            _ => {
+                self.prev_token();
+                None
+            }
+        }
+    }
+
+    fn parse_ident_pair(&mut self) -> Result<IdentPair, ParserError> {
+        Ok(IdentPair(
+            self.parse_identifier()?,
+            self.parse_identifier()?,
+        ))
+    }
+
     pub fn parse_derived_table_factor(
         &mut self,
         lateral: IsLateral,