Fix ruleutils.c's dumping of whole-row Vars in more contexts.

Commit 7745bc352 intended to ensure that whole-row Vars would be
printed with "::type" decoration in all contexts where plain
"var.*" notation would result in star-expansion, notably in
ROW() and VALUES() constructs.  However, it missed the case of
INSERT with a single-row VALUES, as reported by Timur Khanjanov.

Nosing around ruleutils.c, I found a second oversight: the
code for RowCompareExpr generates ROW() notation without benefit
of an actual RowExpr, and naturally it wasn't in sync :-(.
(The code for FieldStore also does this, but we don't expect that
to generate strictly parsable SQL anyway, so I left it alone.)

Back-patch to all supported branches.

Discussion: https://postgr.es/m/efaba6f9-4190-56be-8ff2-7a1674f9194f@intrans.baku.az

1 files changed, 34 insertions, 22 deletions

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 63b85566822..039b1d2b951 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -438,6 +438,8 @@ static void get_rule_expr(Node *node, deparse_context *context,
 						  bool showimplicit);
 static void get_rule_expr_toplevel(Node *node, deparse_context *context,
 								   bool showimplicit);
+static void get_rule_list_toplevel(List *lst, deparse_context *context,
+								   bool showimplicit);
 static void get_rule_expr_funccall(Node *node, deparse_context *context,
 								   bool showimplicit);
 static bool looks_like_function(Node *node);
@@ -6632,7 +6634,7 @@ get_insert_query_def(Query *query, deparse_context *context)
 		/* Add the single-VALUES expression list */
 		appendContextKeyword(context, "VALUES (",
 							 -PRETTYINDENT_STD, PRETTYINDENT_STD, 2);
-		get_rule_expr((Node *) strippedexprs, context, false);
+		get_rule_list_toplevel(strippedexprs, context, false);
 		appendStringInfoChar(buf, ')');
 	}
 	else
@@ -8996,23 +8998,15 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_RowCompareExpr:
 			{
 				RowCompareExpr *rcexpr = (RowCompareExpr *) node;
-				ListCell   *arg;
-				char	   *sep;
 
 				/*
 				 * SQL99 allows "ROW" to be omitted when there is more than
-				 * one column, but for simplicity we always print it.
+				 * one column, but for simplicity we always print it.  Within
+				 * a ROW expression, whole-row Vars need special treatment, so
+				 * use get_rule_list_toplevel.
 				 */
 				appendStringInfoString(buf, "(ROW(");
-				sep = "";
-				foreach(arg, rcexpr->largs)
-				{
-					Node	   *e = (Node *) lfirst(arg);
-
-					appendStringInfoString(buf, sep);
-					get_rule_expr(e, context, true);
-					sep = ", ";
-				}
+				get_rule_list_toplevel(rcexpr->largs, context, true);
 
 				/*
 				 * We assume that the name of the first-column operator will
@@ -9025,15 +9019,7 @@ get_rule_expr(Node *node, deparse_context *context,
 								 generate_operator_name(linitial_oid(rcexpr->opnos),
 														exprType(linitial(rcexpr->largs)),
 														exprType(linitial(rcexpr->rargs))));
-				sep = "";
-				foreach(arg, rcexpr->rargs)
-				{
-					Node	   *e = (Node *) lfirst(arg);
-
-					appendStringInfoString(buf, sep);
-					get_rule_expr(e, context, true);
-					sep = ", ";
-				}
+				get_rule_list_toplevel(rcexpr->rargs, context, true);
 				appendStringInfoString(buf, "))");
 			}
 			break;
@@ -9579,6 +9565,32 @@ get_rule_expr_toplevel(Node *node, deparse_context *context,
 }
 
 /*
+ * get_rule_list_toplevel		- Parse back a list of toplevel expressions
+ *
+ * Apply get_rule_expr_toplevel() to each element of a List.
+ *
+ * This adds commas between the expressions, but caller is responsible
+ * for printing surrounding decoration.
+ */
+static void
+get_rule_list_toplevel(List *lst, deparse_context *context,
+					   bool showimplicit)
+{
+	const char *sep;
+	ListCell   *lc;
+
+	sep = "";
+	foreach(lc, lst)
+	{
+		Node	   *e = (Node *) lfirst(lc);
+
+		appendStringInfoString(context->buf, sep);
+		get_rule_expr_toplevel(e, context, showimplicit);
+		sep = ", ";
+	}
+}
+
+/*
  * get_rule_expr_funccall		- Parse back a function-call expression
  *
  * Same as get_rule_expr(), except that we guarantee that the output will