[CF 5957] v4 - implement CAST(expr AS type FORMAT 'template')

This branch was automatically generated by a robot using patches from an
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https://commitfest.postgresql.org/patch/5957

The branch will be overwritten each time a new patch version is posted to
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on the master branch.

Patch(es): https://www.postgresql.org/message-id/CACJufxH+soqLj_AuMQj-_jxunVQKX-HBQA_3_3vmV1jTRyZ1hA@mail.gmail.com
Author(s): Jian He

Author: Commitfest Bot

src/backend/nodes/nodeFuncs.c

@@ -4464,6 +4464,8 @@ raw_expression_tree_walker_impl(Node *node,
 
 				if (WALK(tc->arg))
 					return true;
+				if (WALK(tc->format))
+					return true;
 				if (WALK(tc->typeName))
 					return true;
 			}

src/backend/parser/gram.y

@@ -156,6 +156,8 @@ static RawStmt *makeRawStmt(Node *stmt, int stmt_location);
 static void updateRawStmtEnd(RawStmt *rs, int end_location);
 static Node *makeColumnRef(char *colname, List *indirection,
 						   int location, core_yyscan_t yyscanner);
+static Node *makeFormattedTypeCast(Node *arg, Node *format,
+								   TypeName *typename, int location);
 static Node *makeTypeCast(Node *arg, TypeName *typename, int location);
 static Node *makeStringConstCast(char *str, int location, TypeName *typename);
 static Node *makeIntConst(int val, int location);
@@ -15933,6 +15935,8 @@ func_expr_common_subexpr:
 				}
 			| CAST '(' a_expr AS Typename ')'
 				{ $$ = makeTypeCast($3, $5, @1); }
+			| CAST '(' a_expr AS Typename FORMAT a_expr ')'
+				{ $$ = makeFormattedTypeCast($3, $7, $5, @1); }
 			| EXTRACT '(' extract_list ')'
 				{
 					$$ = (Node *) makeFuncCall(SystemFuncName("extract"),
@@ -18820,12 +18824,25 @@ makeColumnRef(char *colname, List *indirection,
 	return (Node *) c;
 }
 
+static Node *
+makeFormattedTypeCast(Node *arg, Node *format, TypeName *typename, int location)
+{
+	TypeCast   *n = makeNode(TypeCast);
+
+	n->arg = arg;
+	n->format = format;
+	n->typeName = typename;
+	n->location = location;
+	return (Node *) n;
+}
+
 static Node *
 makeTypeCast(Node *arg, TypeName *typename, int location)
 {
 	TypeCast   *n = makeNode(TypeCast);
 
 	n->arg = arg;
+	n->format = NULL;
 	n->typeName = typename;
 	n->location = location;
 	return (Node *) n;