From ff4fd4bf53c5512427f8ecea08d6ca7777efa2c5 Mon Sep 17 00:00:00 2001
From: Robert Haas <rhaas@postgresql.org>
Date: Tue, 15 Nov 2011 20:34:47 -0500
Subject: [PATCH] Don't elide blank lines when accumulating psql command
 history.

This can change the meaning of queries, if the blank line happens to
occur in the middle of a quoted literal, as per complaint from Tomas Vondra.

Back-patch to all supported branches.
---
 src/bin/psql/input.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/bin/psql/input.c b/src/bin/psql/input.c
index 6628c0c30c..ec0e6e1d49 100644
--- a/src/bin/psql/input.c
+++ b/src/bin/psql/input.c
@@ -95,10 +95,10 @@ void
 pg_append_history(const char *s, PQExpBuffer history_buf)
 {
 #ifdef USE_READLINE
-	if (useHistory && s && s[0])
+	if (useHistory && s)
 	{
 		appendPQExpBufferStr(history_buf, s);
-		if (s[strlen(s) - 1] != '\n')
+		if (!s[0] || s[strlen(s) - 1] != '\n')
 			appendPQExpBufferChar(history_buf, '\n');
 	}
 #endif