From 018b61f81b4aa3c85e2d671d056681ff5c765475 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathan@postgresql.org>
Date: Wed, 19 Jul 2023 15:26:43 -0700
Subject: [PATCH] Rearrange CLUSTER rules in gram.y.

This change moves the unparenthesized syntax for CLUSTER to the end
of the ClusterStmt rules in preparation for a follow-up commit that
will move this syntax to the "Compatibility" section of the CLUSTER
documentation.  The documentation for the CLUSTER syntaxes has also
been consolidated.

Suggested-by: Melanie Plageman
Discussion https://postgr.es/m/CAAKRu_bc5uHieG1976kGqJKxyWtyQt9yvktjsVX%2Bi7NOigDjOA%40mail.gmail.com
---
 doc/src/sgml/ref/cluster.sgml |  5 ++---
 src/backend/parser/gram.y     | 27 +++++++++++++--------------
 2 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/doc/src/sgml/ref/cluster.sgml b/doc/src/sgml/ref/cluster.sgml
index 0ed29a5c6d4..e308e2ce912 100644
--- a/doc/src/sgml/ref/cluster.sgml
+++ b/doc/src/sgml/ref/cluster.sgml
@@ -21,9 +21,8 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-CLUSTER [VERBOSE] <replaceable class="parameter">table_name</replaceable> [ USING <replaceable class="parameter">index_name</replaceable> ]
-CLUSTER ( <replaceable class="parameter">option</replaceable> [, ...] ) <replaceable class="parameter">table_name</replaceable> [ USING <replaceable class="parameter">index_name</replaceable> ]
-CLUSTER [VERBOSE]
+CLUSTER [ ( <replaceable class="parameter">option</replaceable> [, ...] ) ] <replaceable class="parameter">table_name</replaceable> [ USING <replaceable class="parameter">index_name</replaceable> ]
+CLUSTER [ VERBOSE ] [ <replaceable class="parameter">table_name</replaceable> [ USING <replaceable class="parameter">index_name</replaceable> ] ]
 
 <phrase>where <replaceable class="parameter">option</replaceable> can be one of:</phrase>
 
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index edb6c00ece6..91793cb2eff 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11553,15 +11553,24 @@ CreateConversionStmt:
 /*****************************************************************************
  *
  *		QUERY:
- *				CLUSTER [VERBOSE] <qualified_name> [ USING <index_name> ]
- *				CLUSTER [ (options) ] <qualified_name> [ USING <index_name> ]
- *				CLUSTER [VERBOSE]
+ *				CLUSTER (options) <qualified_name> [ USING <index_name> ]
+ *				CLUSTER [VERBOSE] [ <qualified_name> [ USING <index_name> ] ]
  *				CLUSTER [VERBOSE] <index_name> ON <qualified_name> (for pre-8.3)
  *
  *****************************************************************************/
 
 ClusterStmt:
-			CLUSTER opt_verbose qualified_name cluster_index_specification
+			CLUSTER '(' utility_option_list ')' qualified_name cluster_index_specification
+				{
+					ClusterStmt *n = makeNode(ClusterStmt);
+
+					n->relation = $5;
+					n->indexname = $6;
+					n->params = $3;
+					$$ = (Node *) n;
+				}
+			/* unparenthesized VERBOSE kept for pre-14 compatibility */
+			| CLUSTER opt_verbose qualified_name cluster_index_specification
 				{
 					ClusterStmt *n = makeNode(ClusterStmt);
 
@@ -11572,16 +11581,6 @@ ClusterStmt:
 						n->params = lappend(n->params, makeDefElem("verbose", NULL, @2));
 					$$ = (Node *) n;
 				}
-
-			| CLUSTER '(' utility_option_list ')' qualified_name cluster_index_specification
-				{
-					ClusterStmt *n = makeNode(ClusterStmt);
-
-					n->relation = $5;
-					n->indexname = $6;
-					n->params = $3;
-					$$ = (Node *) n;
-				}
 			| CLUSTER opt_verbose
 				{
 					ClusterStmt *n = makeNode(ClusterStmt);