From 10e3ffa305e5a318b4a3ea8cbe8e36cea085e4d7 Mon Sep 17 00:00:00 2001
From: Yugo Nagata <nagata@sraoss.co.jp>
Date: Thu, 5 Jun 2025 09:39:09 +0900
Subject: [PATCH 3/3] Improve tab completion for COPY option lists

Previously, only the first option in a parenthesized list was suggested
during tab completion. Subsequent options after a comma were not completed.
This commit enhances the behavior to suggest valid options after each comma.
---
 src/bin/psql/tab-complete.in.c | 47 +++++++++++++++++++---------------
 1 file changed, 26 insertions(+), 21 deletions(-)

diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c
index 6d10c818ce0..6f8933a73a2 100644
--- a/src/bin/psql/tab-complete.in.c
+++ b/src/bin/psql/tab-complete.in.c
@@ -3300,27 +3300,32 @@ match_previous_words(int pattern_id,
 		COMPLETE_WITH("WITH (", "WHERE");
 
 	/* Complete COPY <sth> FROM|TO [PROGRAM] <sth> WITH ( */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(") ||
-			 Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "("))
-		COMPLETE_WITH("FORMAT", "FREEZE", "DELIMITER", "NULL",
-					  "HEADER", "QUOTE", "ESCAPE", "FORCE_QUOTE",
-					  "FORCE_NOT_NULL", "FORCE_NULL", "ENCODING", "DEFAULT",
-					  "ON_ERROR", "LOG_VERBOSITY");
-
-	/* Complete COPY <sth> FROM|TO [PROGRAM] <sth> WITH (FORMAT */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(", "FORMAT") ||
-			 Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "(", "FORMAT"))
-		COMPLETE_WITH("binary", "csv", "text");
-
-	/* Complete COPY <sth> FROM [PROGRAM] <sth> WITH (ON_ERROR */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(", "ON_ERROR") ||
-			 Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "(", "ON_ERROR"))
-		COMPLETE_WITH("stop", "ignore");
-
-	/* Complete COPY <sth> FROM [PROGRAM] <sth> WITH (LOG_VERBOSITY */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(", "LOG_VERBOSITY") ||
-			 Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "(", "LOG_VERBOSITY"))
-		COMPLETE_WITH("silent", "default", "verbose");
+	else if (HeadMatches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(*") ||
+			 HeadMatches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "(*"))
+	{
+		if (!HeadMatches("COPY|\\copy", MatchAny, "FROM|TO", MatchAnyExcept("PROGRAM"), "WITH", "(*)") &&
+			!HeadMatches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM", MatchAny, "WITH", "(*)"))
+		{
+			/* We're in an unfinished parenthesized option list. */
+			if (ends_with(prev_wd, '(') || ends_with(prev_wd, ','))
+				COMPLETE_WITH("FORMAT", "FREEZE", "DELIMITER", "NULL",
+							  "HEADER", "QUOTE", "ESCAPE", "FORCE_QUOTE",
+							  "FORCE_NOT_NULL", "FORCE_NULL", "ENCODING", "DEFAULT",
+							  "ON_ERROR", "LOG_VERBOSITY");
+
+			/* Complete COPY <sth> FROM|TO filename WITH (FORMAT */
+			else if (TailMatches("FORMAT"))
+				COMPLETE_WITH("binary", "csv", "text");
+
+			/* Complete COPY <sth> FROM filename WITH (ON_ERROR */
+			else if (TailMatches("ON_ERROR"))
+				COMPLETE_WITH("stop", "ignore");
+
+			/* Complete COPY <sth> FROM filename WITH (LOG_VERBOSITY */
+			else if (TailMatches("LOG_VERBOSITY"))
+				COMPLETE_WITH("silent", "default", "verbose");
+		}
+	}
 
 	/* Complete COPY <sth> FROM [PROGRAM] <sth> WITH (<options>) */
 	else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAnyExcept("PROGRAM"), "WITH", MatchAny) ||
-- 
2.43.0