diff --git a/test/common.bash b/test/common.bash
index cd1fc95..a5554b1 100644
--- a/test/common.bash
+++ b/test/common.bash
@@ -68,9 +68,9 @@ teardown() {
 }
 
 setconfig() {
-    if grep -q "$2 =" "${BATS_TMPDIR}/$1"; then
-        sed -i "s/^$2.*/$2 = $3/" "${BATS_TMPDIR}/$1"
+    if grep -qe "$2\s\+=" "${BATS_TMPDIR}/$1"; then
+        sed -i "s/^$2\s\+=.*/$2 = $3/" "${BATS_TMPDIR}/$1"
     else
-        echo "$2 = $3/" >> "${BATS_TMPDIR}/$1"
+        echo "$2 = $3" >> "${BATS_TMPDIR}/$1"
     fi
 }