From 5951ab24529ecc98b1c6da91d23c42b557308489 Mon Sep 17 00:00:00 2001
From: Raziel-23 <venom23@runbox.com>
Date: Tue, 7 Jun 2016 12:39:20 +0200
Subject: [PATCH] core (delete_last_line): add an optional argument for N
 deleted lines

---
 src/core.sh | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/core.sh b/src/core.sh
index 00bc1b2a..2c925c3e 100644
--- a/src/core.sh
+++ b/src/core.sh
@@ -357,10 +357,19 @@ delete_first_line() {
     sed -ne "$((N+1)),\$p"
 }
 
-# Delete last line of a text
+# Delete last line(s) of a text
+# $1: (optional) How many tail lines to delete (default is 1)
 # stdin: input string (multiline)
 delete_last_line() {
-    sed -e '$d'
+    local -r N=${1:-1}
+
+    if (( N < 1 )); then
+        log_error "$FUNCNAME: negative index not expected"
+        return $ERR_FATAL
+    fi
+
+    # Equivalent to `head -n -1` (if $1=1)
+    sed -ne :a -e "1,$N!{P;N;D;};N;ba"
 }
 
 # Check if a string ($2) matches a regexp ($1)