Renaming for new subscripting mechanism

Over at patch https://commitfest.postgresql.org/21/1062/ Dmitry wants to
introduce a more generic subscription mechanism, which allows
subscripting not only arrays but also other object types such as JSONB.
That functionality is introduced in a largish invasive patch, out of
which this internal renaming patch was extracted.

Author: Dmitry Dolgov
Reviewed-by: Tom Lane, Arthur Zakirov
Discussion: https://postgr.es/m/CA+q6zcUK4EqPAu7XRRO5CCjMwhz5zvg+rfWuLzVoxp_5sKS6=w@mail.gmail.com

Author: alvherre

contrib/pg_stat_statements/pg_stat_statements.c

@@ -2579,14 +2579,14 @@ JumbleExpr(pgssJumbleState *jstate, Node *node)
 				JumbleExpr(jstate, (Node *) expr->aggfilter);
 			}
 			break;
-		case T_ArrayRef:
+		case T_SubscriptingRef:
 			{
-				ArrayRef   *aref = (ArrayRef *) node;
+				SubscriptingRef *sbsref = (SubscriptingRef *) node;
 
-				JumbleExpr(jstate, (Node *) aref->refupperindexpr);
-				JumbleExpr(jstate, (Node *) aref->reflowerindexpr);
-				JumbleExpr(jstate, (Node *) aref->refexpr);
-				JumbleExpr(jstate, (Node *) aref->refassgnexpr);
+				JumbleExpr(jstate, (Node *) sbsref->refupperindexpr);
+				JumbleExpr(jstate, (Node *) sbsref->reflowerindexpr);
+				JumbleExpr(jstate, (Node *) sbsref->refexpr);
+				JumbleExpr(jstate, (Node *) sbsref->refassgnexpr);
 			}
 			break;
 		case T_FuncExpr:

contrib/postgres_fdw/deparse.c

@@ -149,7 +149,7 @@ static void deparseExpr(Expr *expr, deparse_expr_cxt *context);
 static void deparseVar(Var *node, deparse_expr_cxt *context);
 static void deparseConst(Const *node, deparse_expr_cxt *context, int showtype);
 static void deparseParam(Param *node, deparse_expr_cxt *context);
-static void deparseArrayRef(ArrayRef *node, deparse_expr_cxt *context);
+static void deparseSubscriptingRef(SubscriptingRef *node, deparse_expr_cxt *context);
 static void deparseFuncExpr(FuncExpr *node, deparse_expr_cxt *context);
 static void deparseOpExpr(OpExpr *node, deparse_expr_cxt *context);
 static void deparseOperatorName(StringInfo buf, Form_pg_operator opform);
@@ -401,34 +401,34 @@ foreign_expr_walker(Node *node,
 					state = FDW_COLLATE_UNSAFE;
 			}
 			break;
-		case T_ArrayRef:
+		case T_SubscriptingRef:
 			{
-				ArrayRef   *ar = (ArrayRef *) node;
+				SubscriptingRef *sr = (SubscriptingRef *) node;
 
 				/* Assignment should not be in restrictions. */
-				if (ar->refassgnexpr != NULL)
+				if (sr->refassgnexpr != NULL)
 					return false;
 
 				/*
-				 * Recurse to remaining subexpressions.  Since the array
+				 * Recurse to remaining subexpressions.  Since the container
 				 * subscripts must yield (noncollatable) integers, they won't
 				 * affect the inner_cxt state.
 				 */
-				if (!foreign_expr_walker((Node *) ar->refupperindexpr,
+				if (!foreign_expr_walker((Node *) sr->refupperindexpr,
 										 glob_cxt, &inner_cxt))
 					return false;
-				if (!foreign_expr_walker((Node *) ar->reflowerindexpr,
+				if (!foreign_expr_walker((Node *) sr->reflowerindexpr,
 										 glob_cxt, &inner_cxt))
 					return false;
-				if (!foreign_expr_walker((Node *) ar->refexpr,
+				if (!foreign_expr_walker((Node *) sr->refexpr,
 										 glob_cxt, &inner_cxt))
 					return false;
 
 				/*
-				 * Array subscripting should yield same collation as input,
-				 * but for safety use same logic as for function nodes.
+				 * Container subscripting should yield same collation as
+				 * input, but for safety use same logic as for function nodes.
 				 */
-				collation = ar->refcollid;
+				collation = sr->refcollid;
 				if (collation == InvalidOid)
 					state = FDW_COLLATE_NONE;
 				else if (inner_cxt.state == FDW_COLLATE_SAFE &&
@@ -2270,8 +2270,8 @@ deparseExpr(Expr *node, deparse_expr_cxt *context)
 		case T_Param:
 			deparseParam((Param *) node, context);
 			break;
-		case T_ArrayRef:
-			deparseArrayRef((ArrayRef *) node, context);
+		case T_SubscriptingRef:
+			deparseSubscriptingRef((SubscriptingRef *) node, context);
 			break;
 		case T_FuncExpr:
 			deparseFuncExpr((FuncExpr *) node, context);
@@ -2518,10 +2518,10 @@ deparseParam(Param *node, deparse_expr_cxt *context)
 }
 
 /*
- * Deparse an array subscript expression.
+ * Deparse a container subscript expression.
  */
 static void
-deparseArrayRef(ArrayRef *node, deparse_expr_cxt *context)
+deparseSubscriptingRef(SubscriptingRef *node, deparse_expr_cxt *context)
 {
 	StringInfo	buf = context->buf;
 	ListCell   *lowlist_item;