From 8350aae4f18a158980c17f56c39a707f4ac168cc Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 15 Feb 2017 14:44:00 -0500 Subject: [PATCH] Fix YA unwanted behavioral difference with operator_precedence_warning. Jeff Janes noted that the error cursor position shown for some errors would vary when operator_precedence_warning is turned on. We'd prefer that option to have no undocumented effects, so this isn't desirable. To fix, make sure that an AEXPR_PAREN node has the same exprLocation as its child node. (Note: it would be a little cheaper to use @2 here instead of an exprLocation call, but there are cases where that wouldn't produce the identical answer, so don't do it like that.) Back-patch to 9.5 where this feature was introduced. Discussion: https://postgr.es/m/CAMkU=1ykK+VhhcQ4Ky8KBo9FoaUJH3f3rDQB8TkTXi-ZsBRUkQ@mail.gmail.com --- src/backend/parser/gram.y | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index 080d444542..ab189a3df2 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -12096,7 +12096,10 @@ c_expr: columnref { $$ = $1; } * AEXPR_PAREN nodes wrapping all explicitly * parenthesized subexpressions; this prevents bogus * warnings from being issued when the ordering has - * been forced by parentheses. + * been forced by parentheses. Take care that an + * AEXPR_PAREN node has the same exprLocation as its + * child, so as not to cause surprising changes in + * error cursor positioning. * * In principle we should not be relying on a GUC to * decide whether to insert AEXPR_PAREN nodes. @@ -12105,7 +12108,8 @@ c_expr: columnref { $$ = $1; } * we'd just as soon not waste cycles on dummy parse * nodes if we don't have to. */ - $$ = (Node *) makeA_Expr(AEXPR_PAREN, NIL, $2, NULL, @1); + $$ = (Node *) makeA_Expr(AEXPR_PAREN, NIL, $2, NULL, + exprLocation($2)); } else $$ = $2; -- 2.40.0