From 9e3b600924c4118002fb36187fa268ba2ac37d9a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Fri, 8 Aug 2025 23:06:36 +0100
Subject: [PATCH v4 3/4] Improve tab completion for RESET

Only complete variables that have been set in the current session,
plus the keywords ALL, ROLE and SESSION (which will subsequently be
completed with AUTHORIZATION).

Because we're using Matches() insted of TailMatches(), we can also get
rid of the guards against ALTER DATABASE|USER|ROLE ... RESET.
---
 src/bin/psql/tab-complete.in.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c
index d31f5780727..c4f50880965 100644
--- a/src/bin/psql/tab-complete.in.c
+++ b/src/bin/psql/tab-complete.in.c
@@ -1047,6 +1047,11 @@ static const SchemaQuery Query_for_trigger_of_table = {
 " WHERE context IN ('user', 'superuser') "\
 "   AND pg_catalog.lower(name) LIKE pg_catalog.lower('%s')"
 
+#define Query_for_list_of_session_vars \
+"SELECT pg_catalog.lower(name) FROM pg_catalog.pg_settings "\
+" WHERE source = 'session' "\
+"   AND pg_catalog.lower(name) LIKE pg_catalog.lower('%s')"
+
 #define Query_for_list_of_show_vars \
 "SELECT pg_catalog.lower(name) FROM pg_catalog.pg_settings "\
 " WHERE pg_catalog.lower(name) LIKE pg_catalog.lower('%s')"
@@ -5027,9 +5032,8 @@ match_previous_words(int pattern_id,
 
 /* SET, RESET, SHOW */
 	/* Complete with a variable name */
-	else if (TailMatches("SET|RESET") &&
-			 !TailMatches("UPDATE", MatchAny, "SET") &&
-			 !TailMatches("ALTER", "DATABASE|USER|ROLE", MatchAny, "RESET"))
+	else if (TailMatches("SET") &&
+			 !TailMatches("UPDATE", MatchAny, "SET"))
 		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_set_vars,
 										  "CONSTRAINTS",
 										  "TRANSACTION",
@@ -5037,6 +5041,12 @@ match_previous_words(int pattern_id,
 										  "ROLE",
 										  "TABLESPACE",
 										  "ALL");
+	/* Complete with variables set in the current session */
+	else if (Matches("RESET"))
+		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_session_vars,
+										  "ALL",
+										  "ROLE",
+										  "SESSION");
 	else if (Matches("SHOW"))
 		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_show_vars,
 										  "SESSION AUTHORIZATION",
-- 
2.50.1

